CN110302562B - Preparation method of molecular imprinting open tubular column - Google Patents
Preparation method of molecular imprinting open tubular column Download PDFInfo
- Publication number
- CN110302562B CN110302562B CN201910649163.5A CN201910649163A CN110302562B CN 110302562 B CN110302562 B CN 110302562B CN 201910649163 A CN201910649163 A CN 201910649163A CN 110302562 B CN110302562 B CN 110302562B
- Authority
- CN
- China
- Prior art keywords
- molecularly imprinted
- modified
- capillary
- open tubular
- solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D15/00—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor
- B01D15/08—Selective adsorption, e.g. chromatography
- B01D15/10—Selective adsorption, e.g. chromatography characterised by constructional or operational features
- B01D15/22—Selective adsorption, e.g. chromatography characterised by constructional or operational features relating to the construction of the column
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/22—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising organic material
- B01J20/26—Synthetic macromolecular compounds
- B01J20/261—Synthetic macromolecular compounds obtained by reactions only involving carbon to carbon unsaturated bonds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/281—Sorbents specially adapted for preparative, analytical or investigative chromatography
- B01J20/286—Phases chemically bonded to a substrate, e.g. to silica or to polymers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2220/00—Aspects relating to sorbent materials
- B01J2220/50—Aspects relating to the use of sorbent or filter aid materials
- B01J2220/52—Sorbents specially adapted for preparative chromatography
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2220/00—Aspects relating to sorbent materials
- B01J2220/50—Aspects relating to the use of sorbent or filter aid materials
- B01J2220/54—Sorbents specially adapted for analytical or investigative chromatography
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2220/00—Aspects relating to sorbent materials
- B01J2220/80—Aspects related to sorbents specially adapted for preparative, analytical or investigative chromatography
- B01J2220/82—Shaped bodies, e.g. monoliths, plugs, tubes, continuous beds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2220/00—Aspects relating to sorbent materials
- B01J2220/80—Aspects related to sorbents specially adapted for preparative, analytical or investigative chromatography
- B01J2220/84—Capillaries
Landscapes
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Chemistry (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Abstract
The invention discloses a preparation method of a molecular imprinting open tubular column, and relates to the technical field of new materials. The preparation method of the molecular imprinting open tubular column comprises the following steps: preparing a molecularly imprinted polymer by using p-hydroxybenzoate as a template molecule, and modifying an epoxy group of the molecularly imprinted polymer to obtain an epoxy-modified molecularly imprinted polymer; performing amino modification on the surface of the capillary to obtain an amino-modified capillary column; dispersing the epoxy modified molecularly imprinted polymer in ethanol to form a mixed solution; and injecting the mixed solution into the amino modified capillary column, sealing, and polymerizing to form a molecular imprinting open tubular column. The invention aims to prepare a molecular imprinting open tubular column which can realize the analysis of p-hydroxybenzoate in a complex sample.
Description
Technical Field
The invention relates to the technical field of new materials, in particular to a preparation method of a molecular imprinting open tubular column.
Background
Parabens (PBs) are synthetic esters of p-hydroxybenzoic acid, including methyl, ethyl, isopropyl, propyl, isobutyl, butyl and the like, as well as their respective sodium salts, and are widely used in the fields of personal care products, pharmaceuticals, foods and the like. However, relevant studies have shown that: PBs have certain endocrine disrupting effects, which can cause the increase in the incidence of breast cancer and the growth of malignant melanoma in women, and there is a certain correlation between these compounds and immune-related diseases, such as allergy, asthma, diabetes and lupus. Generally, personal care products are the primary route by which people expose PBs, accounting for approximately more than 80% of the exposure of people to parabens. Therefore, it is imperative to establish a method for analyzing parabens in personal care products.
The currently common industry standard method is liquid-liquid extraction. However, common personal care products such as creams and body lotions contain very complex matrices, which can reduce the sensitivity of the device and accelerate device wear using standard methods. The solid phase extraction technology can realize the analysis of the parabens in a complex sample. However, the traditional solid phase extraction column lacks specific selectivity for target substances and cannot well remove impurities, thereby having great influence on subsequent analysis and determination. And a plurality of insoluble high-viscosity substances and fine particles contained in the personal care product are easy to block the solid phase extraction column, so that the column efficiency is reduced.
Disclosure of Invention
The invention mainly aims to provide a preparation method of a molecular imprinting open tubular column, and aims to prepare the molecular imprinting open tubular column which can realize the analysis of p-hydroxybenzoate in a complex sample.
In order to achieve the purpose, the invention provides a preparation method of a molecular imprinting open tubular column, which comprises the following steps:
preparing a molecularly imprinted polymer by using p-hydroxybenzoate as a template molecule, and modifying an epoxy group of the molecularly imprinted polymer to obtain an epoxy-modified molecularly imprinted polymer;
performing amino modification on the surface of the capillary to obtain an amino-modified capillary column;
dispersing the epoxy modified molecularly imprinted polymer in ethanol to form a mixed solution;
and injecting the mixed solution into the amino modified capillary column, sealing, and polymerizing to form a molecular imprinting open tubular column.
Optionally, the step of preparing a molecularly imprinted polymer by using paraben as a template molecule and modifying the molecularly imprinted polymer with an epoxy group to obtain the epoxy-modified molecularly imprinted polymer comprises:
adding p-hydroxybenzoate and a functional monomer into an organic solvent to form a pre-polymerization solution;
adding a cross-linking agent and an initiator into the prepolymerization solution, introducing nitrogen to remove oxygen, and carrying out polymerization reaction at 50-80 ℃ to form a primary reaction solution;
adding a toluene solution of glycidyl methacrylate into the primary reaction solution, reacting for 4-10 h, and washing away template molecules to obtain an epoxy modified molecularly imprinted polymer;
wherein the molar ratio of the p-hydroxybenzoate ester to the cross-linking agent to the functional monomer is (5-50): (1-10): 1.
optionally, in the step of adding the paraben and the functional monomer to the organic solvent to form a pre-polymerization solution, the functional monomer is one or both of methacrylic acid and isobutyl vinyl ether.
Optionally, the step of adding a toluene solution of glycidyl methacrylate into the primary reaction solution, reacting for 4-10 hours, and washing away template molecules to obtain the epoxy-modified molecularly imprinted polymer comprises: and after the polymerization reaction is carried out for at least 8 hours, supplementing the initiator into the primary reaction liquid, then sequentially adding a toluene solution of glycidyl methacrylate and the initiator, reacting for 4-10 hours, and washing away template molecules to obtain the epoxy modified molecularly imprinted polymer.
Optionally, in the step of adding a toluene solution of glycidyl methacrylate into the primary reaction solution, reacting for 4-10 hours, and washing away template molecules to obtain the epoxy-modified molecularly imprinted polymer, the mass concentration of glycidyl methacrylate in the toluene solution of glycidyl methacrylate is not greater than 10 (w/w)%.
Optionally, in the step of performing amino modification on the surface of the capillary tube to obtain an amino-modified capillary column, the capillary tube is a polytetrafluoroethylene capillary tube; and/or the presence of a gas in the gas,
the pipe diameter of the capillary is not more than 30 um.
Optionally, the step of performing amino modification on the surface of the capillary to obtain an amino-modified capillary column includes:
injecting an alkaline solution of dopamine into the pretreated capillary tube to obtain the capillary tube with the inner wall modified with hydroxyl groups;
injecting an ethanol solution of 3-glycidyl ether oxypropyl methyl diethoxysilane into the capillary tube with the inner wall modified with the hydroxyl groups, sealing the tube opening, and standing for 5-12 h to obtain a primary capillary tube;
and (3) washing the primary capillary tube until no solvent is left, injecting an ethanol solution of polyethyleneimine into the primary capillary tube, sealing the tube opening, and standing for 10-24 hours to obtain the amino modified capillary tube column.
Optionally, in the step of injecting an ethanol solution of 3-glycidyloxypropylmethyldiethoxysilane into the capillary tube with the inner wall modified with hydroxyl groups, sealing the tube opening, and standing for 5-12 hours to obtain the primary capillary tube, the volume concentration of 3-glycidyloxypropylmethyldiethoxysilane in the ethanol solution of 3-glycidyloxypropylmethyldiethoxysilane is 5-40 (v/v)%.
Optionally, after the primary capillary is washed until no solvent remains, injecting an ethanol solution of polyethyleneimine into the primary capillary, sealing the orifice, standing for 10-24 h to obtain an amino modified capillary column,
the volume concentration of the polyethyleneimine in the polyethyleneimine ethanol solution is 5-30 (v/v)%.
Optionally, after the steps of injecting the mixed solution into the amino-modified capillary column, sealing, and polymerizing to form a molecularly imprinted open-tubular column, the method further comprises: and carrying out molecular imprinting open pipe column molding treatment to form a spiral molecular imprinting open pipe column.
According to the technical scheme, the epoxy group is introduced into the molecularly imprinted polymer taking the p-hydroxybenzoate as the template molecule, so that the selective recognition capability of the molecularly imprinted polymer on the p-hydroxybenzoate is improved, and the matrix interference is reduced. Meanwhile, the inner wall of the capillary is modified, amino is introduced, and the molecularly imprinted material is grafted to the inner wall of the capillary by utilizing the action of the amino and epoxy groups to form an open tubular column with a hollow channel, so that the hollow channel can directly extract a turbid personal care product extracting solution with a complex matrix, the matrix interference is obviously reduced, and the sensitivity of the analysis method is improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other related drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic flow chart of an embodiment of the method for preparing a molecularly imprinted open tubular column according to the present invention;
FIG. 2 is a diagram showing a comparison between the straight-tube molecularly imprinted open tubular column and the spiral molecularly imprinted open tubular column in the embodiment shown in FIG. 1;
FIG. 3 is a schematic flow chart of an embodiment of the method for preparing a molecularly imprinted open tubular column according to the present invention;
FIG. 4 is an electron micrograph of an untreated polytetrafluoroethylene capillary;
FIG. 5 is an electron micrograph of an amino-modified polytetrafluoroethylene capillary column;
FIG. 6 is an electron micrograph of an epoxy-modified molecularly imprinted polymer;
FIG. 7 is an electron microscope image of a molecularly imprinted open tubular column prepared by the method for preparing the molecularly imprinted open tubular column provided by the invention;
FIG. 8 is a liquid chromatogram of an analysis of a bath sample;
FIG. 9 is a liquid chromatogram of shampoo sample analysis.
The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments.
It should be noted that those whose specific conditions are not specified in the examples were performed according to the conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially. In addition, the meaning of "and/or" appearing throughout includes three juxtapositions, exemplified by "A and/or B" including either A or B or both A and B. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Personal care products are the primary route by which people expose PBs, accounting for approximately more than 80% of the exposure of people to parabens. Therefore, it is imperative to establish a method for analyzing parabens in personal care products.
The currently common industry standard method is liquid-liquid extraction. However, common personal care products such as creams and body lotions contain very complex matrices, which can reduce the sensitivity of the device and accelerate device wear using standard methods. The solid phase extraction technology can realize the analysis of the parabens in a complex sample. However, the traditional solid phase extraction column lacks specific selectivity for target substances and cannot well remove impurities, thereby having great influence on subsequent analysis and determination. And a plurality of insoluble high-viscosity substances and fine particles contained in the personal care product are easy to block the solid phase extraction column, so that the column efficiency is reduced.
In view of this, the invention provides a method for preparing a molecular imprinting open tubular column, which can be used for preparing a molecular imprinting open tubular column having a microstructure as shown in fig. 7, having a high selective recognition capability for parabens, being applicable to samples with complex components, and being not easily interfered by a matrix. Specifically, the molecularly imprinted open tubular column prepared by the preparation method comprises a capillary column and a molecularly imprinted polymer layer grafted on the inner wall of the capillary column. Wherein, the surface of the capillary column is modified with amino groups; the molecularly imprinted polymer layer is prepared by taking p-hydroxybenzoate as a template molecule, the surface of the molecularly imprinted polymer layer is modified with epoxy groups, the molecularly imprinted polymer layer has high selective recognition capability on the p-hydroxybenzoate, and matrix interference can be reduced. In addition, the preparation method of the invention utilizes the action of amino and epoxy groups to graft the molecularly imprinted polymer layer on the inner wall of the capillary column to form an open tubular column with a hollow channel, and the hollow channel can directly extract the turbid personal care product extract with a complex matrix, thereby obviously reducing matrix interference and improving the sensitivity of the analysis method.
Fig. 1 and fig. 2 show an embodiment of a method for preparing a molecularly imprinted open tubular column according to the present invention.
Referring to fig. 1, in an embodiment of the method for preparing a molecular imprinting open tubular column, the method for preparing a molecular imprinting open tubular column includes the following steps:
s100, preparing a molecularly imprinted polymer by using p-hydroxybenzoate as a template molecule, and modifying an epoxy group of the molecularly imprinted polymer to obtain the epoxy-modified molecularly imprinted polymer.
The molecular imprinting technology refers to a preparation and application technology of a polymer having specific recognition on a specific target molecule (template molecule) and a structural analog thereof. Molecularly Imprinted Polymers (MIPs) can selectively identify template molecules in a complex system, have the advantages of strong adverse environment resistance, good stability, long service life and the like, make up the defects of the traditional solid phase extraction method, and gradually become a research hotspot. The molecularly imprinted polymer prepared by taking the p-hydroxybenzoate as the template molecule is further subjected to epoxy group modification to obtain a microstructure shown in figure 6, so that on one hand, preconditions can be created for preparing a capillary open tubular column, the molecularly imprinted polymer is convenient to fix on the inner wall of the capillary in a subsequent process, and on the other hand, the selectivity of the molecularly imprinted polymer can be improved.
It is understood that parabens are a class of synthetic esters of parahydroxybenzoic acid, including methyl parahydroxybenzoate, ethyl parahydroxybenzoate, isopropyl parahydroxybenzoate, propyl parahydroxybenzoate, isobutyl parahydroxybenzoate, butyl parahydroxybenzoate, and the like, and their respective sodium salts. Thus, in this embodiment, the paraben of the template molecule can be methyl paraben, ethyl paraben, isopropyl paraben, propyl paraben, isobutyl paraben, butyl paraben, and the like, and their respective sodium salts.
In the implementation, a molecularly imprinted polymer can be prepared by adopting a template molecule polymerization method, and then an epoxy group is introduced to modify the surface of the molecularly imprinted polymer under the action of an initiator. The present invention is not limited to the specific method for preparing the molecularly imprinted polymer and introducing the epoxy group in step S100, and in the specific implementation, step S100 can be implemented by using any of the existing methods for forming the molecularly imprinted polymer by template molecular polymerization and methods for introducing the epoxy group into the molecularly imprinted polymer. In order to introduce the epoxy group without affecting the selectivity of the original imprinted pores of the molecularly imprinted polymer, in an embodiment of the preparation method of the present invention, step S100 may include the following steps, so that the selectivity of the paraben molecularly imprinted polymer is not affected, but the selective adsorption capacity of the paraben molecularly imprinted polymer on paraben is further improved:
step S110, adding p-hydroxybenzoic ester and functional monomer to an organic solvent to form a pre-polymerization solution.
In this example, parabens are template molecules; the organic solvent is acetonitrile or methanol; the functional monomer is one or two of methacrylic acid and isobutyl vinyl ether, and is preferably a mixture of the methacrylic acid and the isobutyl vinyl ether. In the specific implementation, the p-hydroxybenzoate ester and the functional monomer are mixed according to the molar ratio (5-50): 1, and pre-polymerizing for a period of time at normal temperature, wherein the molar ratio of the added p-hydroxybenzoate ester to the added functional monomer can be 5:1, 8: 1. 10:1, 15:1, 24:1, 30:1, 35:1, 40:1, 45:1, 50:1, etc. Wherein the normal temperature is 20-30 ℃, and the period of time is 0-30 min, that is, the step S20 can be started immediately after the p-hydroxybenzoate and the functional monomer are added into the organic solvent in proportion, or the p-hydroxybenzoate and the functional monomer are added into the organic solvent in proportion and then react at 20-30 ℃, and the reaction time is not more than 30 min.
And S120, adding a cross-linking agent and an initiator into the prepolymerization solution, introducing nitrogen to remove oxygen, and carrying out polymerization reaction at 50-80 ℃ to form a primary reaction solution.
In the present embodiment, specific kinds of the crosslinking agent and the initiator are not limited, and the crosslinking agent and the initiator may be any commercially available crosslinking agent and initiator as long as the crosslinking agent and the initiator can promote the polymerization reaction to proceed smoothly. From the viewpoint of reaction efficiency and yield, the crosslinking agent may include divinylbenzene, trimethylolpropane trimethacrylate or ethylene glycol dimethacrylate, preferably ethylene glycol dimethacrylate, in a molar ratio to the functional monomer of (1 to 10): 1; the initiator can comprise azobisisobutyronitrile, ammonium persulfate or a bromo initiator, preferably azobisisobutyronitrile, and the dosage of the initiator can be 1-30 mg.
In addition, the nitrogen introduction and the oxygen removal include that nitrogen is continuously introduced into the reaction system to exhaust air in the system, so that the reaction system is in an oxygen-free environment, in this embodiment, the time for introducing nitrogen and removing oxygen does not exceed 30min, namely 5min, 10min, 12min, 15min, 20min, 24min, 30min and the like; the time of the polymerization reaction is 8-24 h.
And S130, adding a toluene solution of glycidyl methacrylate into the primary reaction solution, reacting for 4-10 hours, and washing away template molecules to obtain the epoxy modified molecularly imprinted polymer.
Wherein the mass concentration of glycidyl methacrylate in the toluene solution of glycidyl methacrylate is not more than 10 (w/w)%. The preparation method comprises the following steps: dissolving glycidyl methacrylate in toluene to obtain a toluene solution of glycidyl methacrylate, wherein the weight of the glycidyl methacrylate accounts for not more than 10 (w/w)% of the total weight of the toluene solution of glycidyl methacrylate.
In a specific implementation, step S130 may be performed by:
and after the polymerization reaction is carried out for at least 8 hours, supplementing the initiator into the primary reaction liquid, then sequentially adding a toluene solution of glycidyl methacrylate and the initiator, reacting for 4-10 hours, and washing away template molecules to obtain the epoxy modified molecularly imprinted polymer. In specific implementation, the steps of replenishing the initiator and adding the toluene solution of glycidyl methacrylate are carried out near the end of the polymerization reaction, and are reflected in time, that is, when the polymerization reaction starts for 8h to 24h and the reaction is not finished, for example, the initiator may be replenished and the toluene solution of glycidyl methacrylate may be added at the time points of 8h, 9h, 10h, 12h, 15h, 18h, 20h, 21h, 22h and the like after the polymerization reaction starts.
The template molecule is p-hydroxybenzoate ester, and the template molecule can be washed away by repeatedly extracting the reaction solution with solvents such as acetonitrile and methanol, and the extraction method can be soxhlet extraction or ultrasonic-assisted extraction. It is understood that the step of washing away the template molecule can be performed after the epoxy-modified molecularly imprinted polymer is prepared, as shown in step S1301 above, or after the epoxy-modified molecularly imprinted polymer is grafted onto the inner wall of the amino-modified capillary column.
Further, step S130 may also be performed by: and after the polymerization reaction is carried out for at least 8 hours, centrifuging the primary reaction liquid, removing the supernatant, adding the initiator, then sequentially adding a toluene solution of glycidyl methacrylate and the initiator, continuously reacting for 4-10 hours, and washing away the template molecules to obtain the epoxy modified molecularly imprinted polymer.
And S200, performing amino modification on the surface of the capillary to obtain an amino-modified capillary column.
The capillary tube can be made of polytetrafluoroethylene, is relatively soft and is suitable for being made into various shapes. In addition, the smaller the tube diameter of the capillary column is, the better the extraction effect of the finally prepared molecular imprinting open-tubular column is, and therefore, in the embodiment, the tube diameter of the capillary is not more than 30 um.
Taking a polytetrafluoroethylene capillary as an example, the untreated polytetrafluoroethylene capillary has a microstructure shown in fig. 4, and a plurality of amino groups are introduced into the surface of the inner wall of the polytetrafluoroethylene capillary through amino modification treatment, as shown in fig. 5, so that the molecularly imprinted polymer on the inner wall of the capillary can be immobilized by amino-epoxy crosslinking to form an open tubular column (as shown in fig. 7).
In a specific implementation, step S200 may include:
and step S210, injecting an alkaline solution of dopamine into the pretreated capillary to obtain the capillary with the inner wall modified with hydroxyl groups.
In specific implementation, step S210 can be implemented by the following steps:
s211, corroding the inner wall of the capillary tube by using 0.1-1 mol/L sulfuric acid solution, washing with water, and drying by using nitrogen to obtain a pretreated capillary tube;
step S212, dissolving dopamine in a Tris-HCl buffer solution to obtain a dopamine alkaline solution with the pH value of 8.5;
and S213, continuously introducing the dopamine alkaline solution into the pretreated capillary tube for 2-3 hours to obtain the capillary tube with the inner wall modified with hydroxyl groups.
And S220, injecting an ethanol solution of 3-glycidyl ether oxypropyl methyl diethoxysilane into the capillary tube with the inner wall modified with the hydroxyl groups, sealing the tube opening, and standing for 5-12 hours to obtain the primary capillary tube.
In the embodiment, after an ethanol solution of 3-glycidyl ether oxypropyl methyldiethoxysilane is injected into the capillary tube with the inner wall modified with hydroxyl groups, the tube openings at the two ends of the capillary tube are sealed, and the capillary tube is allowed to stand at room temperature for 5-12 hours, so that the primary capillary tube is obtained. Wherein the volume concentration of 3-glycidyloxypropylmethyldiethoxysilane in the 3-glycidyloxypropylmethyldiethoxysilane ethanol solution is 5 to 40 (v/v)%, i.e., the volume of 3-glycidyloxypropylmethyldiethoxysilane is 5 to 40 (v/v)%, based on the total volume of the 3-glycidyloxypropylmethyldiethoxysilane ethanol solution.
And S230, washing the primary capillary tube until no solvent remains, injecting an ethanol solution of polyethyleneimine into the primary capillary tube, sealing the tube opening, and standing for 10-24 hours to obtain the amino modified capillary tube.
Wherein the volume concentration of the polyethyleneimine in the polyethyleneimine ethanol solution is 5-30 (v/v)%, namely the volume of the polyethyleneimine accounts for 5-30 (v/v)% of the total volume of the polyethyleneimine ethanol solution.
Step S300, dispersing the epoxy modified molecularly imprinted polymer in ethanol to form a mixed solution.
And S400, injecting the mixed solution into the amino modified capillary column, sealing, and polymerizing to form a molecular imprinting open tubular column.
In this embodiment, the mixed solution is injected into the amino-modified capillary column, the openings at the two ends of the capillary are closed, and then the capillary column is subjected to a polymerization reaction for 4-8 hours at a constant temperature of 30-80 ℃ to obtain a molecular imprinting open tubular column, wherein the microstructure of the molecular imprinting open tubular column is shown in fig. 7.
In addition, the open tubular column manufactured by the embodiment of the present invention may be a straight tube, as shown in fig. 2 (a), or may be a bent tube. Based on this, in another embodiment of the present invention, after step S400, step S500 is further included: and carrying out molecular imprinting open pipe column molding treatment to form a spiral molecular imprinting open pipe column. Thus, the molecularly imprinted open tubular column is spiral, as shown in fig. 2 (B), the solution to be detected can flow in a turbulent flow manner in the tubular column after entering the open tubular column, so that the contact chance of the object to be detected and the imprinted hole is remarkably increased, and the extraction efficiency and the selective recognition capability of the molecularly imprinted open tubular column are enhanced.
The molding method can be as follows: and selecting a core column with a certain pipe diameter, winding the molecular imprinting open tubular column on the outer wall of the core column, and extracting the core column to obtain the spiral molecular imprinting open tubular column. Wherein, this stem can be wire, pipe etc. and its pipe diameter can be adjusted according to actual demand.
FIG. 3 is a schematic flow chart of another embodiment of the preparation method of the molecularly imprinted open tubular column of the present invention.
Parabens are a class of synthetic esters of parahydroxybenzoic acid, including methyl parahydroxybenzoate, ethyl parahydroxybenzoate, isopropyl parahydroxybenzoate, propyl parahydroxybenzoate, isobutyl parahydroxybenzoate, butyl parahydroxybenzoate, and the like, and their respective sodium salts. Taking ethyl p-hydroxybenzoate as an example, a preparation method for obtaining a molecularly imprinted open tubular column with high selective recognition capability on ethyl p-hydroxybenzoate is shown in fig. 3. Referring to fig. 3, in this embodiment, after adding ethyl p-hydroxybenzoate (a) and a functional monomer [ a mixture of methacrylic acid (b) and isobutyl vinyl ether (c) ] into an organic solvent at normal temperature to form a pre-polymerization solution, adding a crosslinking agent ethylene glycol dimethacrylate (d) and an initiator azobisisobutyronitrile (e), introducing nitrogen to remove oxygen, and performing a polymerization reaction at 50-80 ℃ to form a primary reaction solution, wherein a main component in the primary reaction solution is a molecularly imprinted polymer (f); and adding a toluene solution (g) of glycidyl methacrylate into the primary reaction solution, reacting for 4-10 h to obtain an epoxy modified molecularly imprinted polymer (h) containing template molecules, and washing off the template molecules of ethyl p-hydroxybenzoate (a) to obtain the epoxy modified molecularly imprinted polymer (n). Wherein the molar ratio of the p-hydroxybenzoate ester to the cross-linking agent to the functional monomer is (5-50): (1-10): 1.
injecting an alkaline solution of dopamine into a pretreated polytetrafluoroethylene capillary to obtain a capillary (i) with a modified hydroxyl group on the inner wall, injecting an ethanol solution (j) of 3-glycidyl ether oxypropyl methyl diethoxysilane into the capillary (i) with the modified hydroxyl group on the inner wall, sealing the orifice of the capillary, and standing for 5-12 h to obtain a primary capillary (k); and (3) washing the primary capillary (k) until no solvent is left, injecting an ethanol solution (l) of polyethyleneimine into the primary capillary, sealing the pipe orifice, and standing for 10-24 h to obtain the amino modified capillary column (m).
Dispersing the epoxy modified molecularly imprinted polymer (n) in ethanol to form a mixed solution, injecting the mixed solution into an amino modified capillary column (m), sealing pipe orifices at two ends of the capillary, and then carrying out polymerization reaction for 4 hours at a constant temperature of 30 ℃ to obtain a molecularly imprinted open tubular column (o). The molecular imprinting open tubular column (o) has high selective recognition capability on the ethyl p-hydroxybenzoate (a), and can form a structure shown in the formula (p) after adsorbing the ethyl p-hydroxybenzoate (a), wherein the process between the structure (o) and the structure (p) is reversible, namely the molecular imprinting open tubular column (o) adsorbs the ethyl p-hydroxybenzoate to form the structure (p), and then the molecular imprinting open tubular column (o) can be obtained again after washing the ethyl p-hydroxybenzoate.
And (3) forming the molecular imprinting open tubular column (o) into a spiral shape to obtain the spiral molecular imprinting open tubular column.
It is understood that in other embodiments of the present invention, the template molecule can be replaced by parabens such as methyl paraben, isopropyl paraben, propyl paraben, isobutyl paraben, butyl paraben and their respective sodium salts, and the specific procedures are as described above and will not be described in detail herein.
The technical solutions of the present invention are further described in detail below with reference to specific examples and drawings, it should be understood that the following examples are merely illustrative of the present invention and are not intended to limit the present invention.
Example 1
Mixing p-hydroxybenzoate and a functional monomer (a mixture of methacrylic acid and isobutyl vinyl ether) according to a molar ratio of 5:1, pre-polymerizing for 1min at normal temperature, adding cross-linking agent ethylene glycol dimethacrylate (molar ratio of 10:1 to functional monomer) and initiator Azobisisobutyronitrile (AIBN) 1mg, introducing nitrogen to remove oxygen for 1 min. Then the mixture is placed at 50 ℃ for polymerization reaction for 8 h. At the 8 th hour of the reaction, 1mg of azobisisobutyronitrile as an initiator was added, followed by 20mL of a 1 (w/w)% by mass solution of glycidyl methacrylate in toluene and 1mg of azobisisobutyronitrile as an initiator, and the reaction was continued for 4 hours. And removing the template by using an organic solvent to obtain the epoxy modified molecularly imprinted polymer.
Dissolving dopamine in Tris-HCl buffer solution to obtain dopamine alkaline solution with pH8.5 for later use. A polytetrafluoroethylene capillary tube with the inner diameter of 30 mu m is taken, and the inner wall of the capillary tube is corroded by 0.1mol/L sulfuric acid solution. And (3) flushing the capillary tube with water, blowing the dopamine alkaline solution into the capillary tube for 2-3 hours after drying the capillary tube with nitrogen, and obtaining the capillary tube with the inner wall modified with hydroxyl groups. And injecting 5 (v/v)% volume concentration ethanol solution of 3-glycidyl ether oxypropyl methyl diethoxysilane into the capillary with the modified hydroxyl group on the inner wall, sealing the pipe orifice, and standing for 5 h. And (3) washing the tube wall by using ethanol, injecting an ethanol solution of polyethyleneimine with the volume concentration of 5 (v/v)% into the tube, sealing the tube openings at two ends, and standing for 10 hours to obtain the amino modified capillary column.
Dispersing the epoxy modified molecularly imprinted polymer in ethanol to form a mixed solution, injecting the mixed solution into an amino modified capillary column, sealing pipe orifices at two ends of the capillary, and then performing polymerization reaction for 4 hours at a constant temperature of 30 ℃ to obtain a molecularly imprinted open tubular column.
And (3) forming the molecular imprinting open tubular column into a spiral shape to obtain the spiral molecular imprinting open tubular column.
Example 2
Mixing p-hydroxybenzoate and a functional monomer (a mixture of methacrylic acid and isobutyl vinyl ether) according to a molar ratio of 10:1, pre-polymerizing for 20min at normal temperature, adding cross-linking agent ethylene glycol dimethacrylate (molar ratio of 5:1 to functional monomer) and initiator azobisisobutyronitrile 10mg, introducing nitrogen to remove oxygen for 5 min. Then the mixture is placed at 60 ℃ for polymerization reaction for 12 h. At the 10 th reaction hour, 3mg of azobisisobutyronitrile as an initiator was added, followed by 20mL of a toluene solution of glycidyl methacrylate (8 (w/w)% by mass) and 5mg of azobisisobutyronitrile as an initiator, and the reaction was continued for 6 hours. And removing the template by using an organic solvent to obtain the epoxy modified molecularly imprinted polymer.
Dissolving dopamine in Tris-HCl buffer solution to obtain dopamine alkaline solution with pH8.5 for later use. A polytetrafluoroethylene capillary tube with the inner diameter of 30 mu m is taken, and the inner wall of the capillary tube is corroded by 1mol/L sulfuric acid solution. And (3) flushing the capillary tube with water, blowing the dopamine alkaline solution into the capillary tube for 2-3 hours after drying the capillary tube with nitrogen, and obtaining the capillary tube with the inner wall modified with hydroxyl groups. And injecting 5 (v/v)% volume concentration ethanol solution of 3-glycidyl ether oxypropyl methyl diethoxysilane into the capillary with the modified hydroxyl group on the inner wall, sealing the pipe orifice, and standing for 8 hours. And (3) washing the tube wall by using ethanol, injecting an ethanol solution of polyethyleneimine with the volume concentration of 5 (v/v)% into the tube, sealing the tube openings at two ends, and standing for 16h to obtain the amino modified capillary column.
Dispersing the epoxy modified molecularly imprinted polymer in ethanol to form a mixed solution, injecting the mixed solution into an amino modified capillary column, sealing pipe orifices at two ends of the capillary, and then performing polymerization reaction for 6 hours at a constant temperature of 60 ℃ to obtain a molecularly imprinted open tubular column.
And (3) forming the molecular imprinting open tubular column into a spiral shape to obtain the spiral molecular imprinting open tubular column.
Example 3
Mixing p-hydroxybenzoate and a functional monomer (a mixture of methacrylic acid and isobutyl vinyl ether) according to a molar ratio of 50:1, pre-polymerizing for 30min at normal temperature, adding cross-linking agent ethylene glycol dimethacrylate (molar ratio of 1: 1 to functional monomer) and initiator azobisisobutyronitrile 30mg, introducing nitrogen to remove oxygen for 30 min. Then the mixture is placed at 80 ℃ for polymerization reaction for 24 hours. And (3) adding 10mg of azodiisobutyronitrile serving as an initiator during the reaction for 20h, then adding 10 (w/w)% of a glycidyl methacrylate toluene solution serving as the initiator and 10mg of azodiisobutyronitrile serving as the initiator, and continuing the reaction for 10 h. And removing the template by using an organic solvent to obtain the epoxy modified molecularly imprinted polymer.
Dissolving dopamine in Tris-HCl buffer solution to obtain dopamine alkaline solution with pH8.5 for later use. A polytetrafluoroethylene capillary tube with the inner diameter of 30 mu m is taken, and the inner wall of the capillary tube is corroded by 1mol/L sulfuric acid solution. And (3) flushing the capillary tube with water, blowing the dopamine alkaline solution into the capillary tube for 2-3 hours after drying the capillary tube with nitrogen, and obtaining the capillary tube with the inner wall modified with hydroxyl groups. And injecting an ethanol solution of 3-glycidyloxypropylmethyldiethoxysilane with the volume concentration of 40 (v/v)% into the capillary with the modified hydroxyl group on the inner wall, sealing the pipe orifice, and standing for 12 hours. And (3) washing the tube wall by using ethanol, injecting 30 (v/v)% volume concentration ethanol solution of polyethyleneimine into the tube, sealing the tube openings at two ends, and standing for 24 hours to obtain the amino modified capillary column.
Dispersing the epoxy modified molecularly imprinted polymer in ethanol to form a mixed solution, injecting the mixed solution into an amino modified capillary column, sealing pipe orifices at two ends of the capillary, and then performing polymerization reaction for 8 hours at a constant temperature of 80 ℃ to obtain a molecularly imprinted open tubular column.
And (3) forming the molecular imprinting open tubular column into a spiral shape to obtain the spiral molecular imprinting open tubular column.
Example 4
Mixing p-hydroxybenzoate and a functional monomer (methacrylic acid) according to a molar ratio of 20: 1, adding the mixture into acetonitrile or methanol, prepolymerizing for 10min at normal temperature, adding a crosslinking agent of divinylbenzene, (the molar ratio of the divinylbenzene to the functional monomer is 7: 1), and 30mg of an initiator of ammonium persulfate, introducing nitrogen, and deoxidizing for 10 min. Then placing the mixture at 70 ℃ for polymerization reaction for 15h to obtain primary reaction liquid. And at the 15 th reaction hour, centrifuging the primary reaction liquid, removing the supernatant, adding 10mg of initiator ammonium persulfate, then adding 5 (w/w)% of glycidyl methacrylate toluene solution and 10mg of initiator ammonium persulfate, and continuing the reaction for 7 hours. And removing the template by using an organic solvent to obtain the epoxy modified molecularly imprinted polymer.
Dissolving dopamine in Tris-HCl buffer solution to obtain dopamine alkaline solution with pH8.5 for later use. A polytetrafluoroethylene capillary tube with the inner diameter of 10 mu m is taken, and the inner wall of the capillary tube is corroded by 0.5mol/L sulfuric acid solution. And (3) flushing the capillary tube with water, blowing the dopamine alkaline solution into the capillary tube for 2-3 hours after drying the capillary tube with nitrogen, and obtaining the capillary tube with the inner wall modified with hydroxyl groups. And injecting an ethanol solution of 3-glycidyl ether oxypropyl methyl diethoxysilane with the volume concentration of 10 (v/v)% into the capillary with the modified hydroxyl group on the inner wall, sealing the pipe orifice, and standing for 9 hours. And (3) washing the tube wall by using ethanol, injecting an ethanol solution of polyethyleneimine with the volume concentration of 20 (v/v)% into the tube, sealing the tube openings at two ends, and standing for 16h to obtain the amino modified capillary column.
Dispersing the epoxy modified molecularly imprinted polymer in ethanol to form a mixed solution, injecting the mixed solution into an amino modified capillary column, sealing pipe orifices at two ends of the capillary, and then performing polymerization reaction for 5 hours at a constant temperature of 50 ℃ to obtain a molecularly imprinted open tubular column.
And (3) forming the molecular imprinting open tubular column into a spiral shape to obtain the spiral molecular imprinting open tubular column.
Example 5
P-hydroxybenzoate and a functional monomer (isobutyl vinyl ether) were added in a molar ratio of 35:1 into acetonitrile or methanol, prepolymerizing at normal temperature for 5min, adding cross-linking agent trimethylolpropane trimethacrylate (molar ratio of 4:1 to functional monomer) and initiator bromization initiator 3mg, introducing nitrogen to remove oxygen for 15 min. Then the mixture is put at 75 ℃ for polymerization reaction for 12 hours to obtain primary reaction liquid. And (3) centrifuging the primary reaction liquid during the reaction for 12h, removing the supernatant, adding 1mg of initiator bromination initiator, then adding a toluene solution of glycidyl methacrylate with the mass concentration of 3 (w/w)% and 1mg of initiator bromination initiator, and continuing the reaction for 8 h. And removing the template by using an organic solvent to obtain the epoxy modified molecularly imprinted polymer.
Dissolving dopamine in Tris-HCl buffer solution to obtain dopamine alkaline solution with pH8.5 for later use. A polytetrafluoroethylene capillary tube with an inner diameter of 20 mu m is taken, and the inner wall of the capillary tube is corroded by 0.1-1 mol/L sulfuric acid solution. And (3) flushing the capillary tube with water, blowing the dopamine alkaline solution into the capillary tube for 2-3 hours after drying the capillary tube with nitrogen, and obtaining the capillary tube with the inner wall modified with hydroxyl groups. And injecting an ethanol solution of 25 (v/v)% volume concentration of 3-glycidyl ether oxypropyl methyldiethoxysilane into the capillary modified with hydroxyl groups on the inner wall, sealing the tube orifice, and standing for 11 h. And (3) washing the tube wall by using ethanol, injecting an ethanol solution of polyethyleneimine with the volume concentration of 15 (v/v)% into the tube, sealing the tube openings at two ends, and standing for 18h to obtain the amino modified capillary column.
Dispersing the epoxy modified molecularly imprinted polymer in ethanol to form a mixed solution, injecting the mixed solution into an amino modified capillary column, sealing pipe orifices at two ends of the capillary, and then performing polymerization reaction for 7 hours at a constant temperature of 70 ℃ to obtain a molecularly imprinted open tubular column.
And (3) forming the molecular imprinting open tubular column into a spiral shape to obtain the spiral molecular imprinting open tubular column.
Comparative example 1
Mixing p-hydroxybenzoate and a functional monomer (a mixture of methacrylic acid and isobutyl vinyl ether) according to a molar ratio of 5:1, pre-polymerizing for 1min at normal temperature, adding cross-linking agent ethylene glycol dimethacrylate (molar ratio of 10:1 to functional monomer) and initiator Azobisisobutyronitrile (AIBN) 1mg, introducing nitrogen to remove oxygen for 1 min. Then placing the mixture at 50 ℃ for polymerization reaction for 8h to obtain the molecularly imprinted polymer.
Comparative example 2
Mixing p-hydroxybenzoate and a functional monomer (a mixture of methacrylic acid and isobutyl vinyl ether) according to a molar ratio of 5:1, pre-polymerizing for 1min at normal temperature, adding cross-linking agent ethylene glycol dimethacrylate (molar ratio of 10:1 to functional monomer) and initiator Azobisisobutyronitrile (AIBN) 1mg, introducing nitrogen to remove oxygen for 1 min. Then the mixture is placed at 50 ℃ for polymerization reaction for 8 h. And at the 8 th hour of reaction, centrifuging to remove the supernatant, adding 1mg of azodiisobutyronitrile serving as an initiator again, adding 20mL of a toluene solution of 1 (w/w)% of glycidyl methacrylate serving as a mass concentration and 1mg of azodiisobutyronitrile serving as an initiator, and continuing to react for 4 hours. And removing the template by using an organic solvent to obtain the epoxy modified molecularly imprinted polymer.
Comparative example 3
Mixing p-hydroxybenzoate and a functional monomer (a mixture of methacrylic acid and isobutyl vinyl ether) according to a molar ratio of 5:1, pre-polymerizing for 1min at normal temperature, adding cross-linking agent ethylene glycol dimethacrylate (molar ratio of 10:1 to functional monomer) and initiator Azobisisobutyronitrile (AIBN) 1mg, introducing nitrogen to remove oxygen for 1 min. Then the mixture is placed at 50 ℃ for polymerization reaction for 8 h. And at the 8 th hour of reaction, centrifuging to remove the supernatant, adding 1mg of azodiisobutyronitrile serving as an initiator again, adding 20mL of a toluene solution of 1 (w/w)% of glycidyl methacrylate serving as a mass concentration and 1mg of azodiisobutyronitrile serving as an initiator, and continuing to react for 4 hours. And removing the template by using an organic solvent to obtain the epoxy modified molecularly imprinted polymer.
Dissolving dopamine in Tris-HCl buffer solution to obtain dopamine alkaline solution with pH8.5 for later use. A polytetrafluoroethylene capillary tube with an inner diameter of 30 mu m is taken, and the inner wall of the capillary tube is corroded by 0.1-1 mol/L sulfuric acid solution. And (3) washing the capillary tube with water, drying the capillary tube with nitrogen, and continuously introducing the dopamine alkaline solution into the capillary tube for 2-3 hours to obtain a capillary column for later use.
Dispersing the epoxy modified molecularly imprinted polymer in ethanol to form a mixed solution, injecting the mixed solution into a capillary column, sealing pipe orifices at two ends of the capillary, and then performing polymerization reaction for 4 hours at a constant temperature of 30 ℃ to obtain a molecularly imprinted open tubular column.
And (3) forming the molecular imprinting open tubular column into a spiral shape to obtain the spiral molecular imprinting open tubular column.
Performance testing
Samples of methyl paraben, ethyl paraben, propyl paraben, isopropyl paraben, butyl paraben, isobutyl paraben, p-hydroxybenzoic acid, phenol and benzene were taken and tested for adsorption performance for each of the examples described above as well as for the comparative product.
The detection method comprises the following steps: after the samples were subjected to ultrasonic extraction with acetonitrile, the extraction solution was injected into the product to be tested at a flow rate of 400uL/min, followed by washing with 1mL of water to remove the adsorbed impurities from the product to be tested, then eluting with 250uL90 (v/v)% methanol acetic acid solution, and analyzing the adsorption capacity (mg/g) of each product on the samples by HPLC-UV detection. The analysis results are shown in table 1.
TABLE 1 adsorption Performance test (mg/g)
As can be seen from the data in table 1 above, each of examples, comparative example 1, and comparative example 3 exhibited the highest adsorption capacity for parabens, indicating that the epoxy-modified molecularly imprinted polymer was able to identify parabens having a common structure. Meanwhile, in the detection of the same sample, each embodiment shows better adsorption effect than each proportion, which shows that the combination of the epoxy modified molecular polymer and the amino modified capillary column has better adsorption performance.
The bath foam and shampoo produced by Baojie company are selected as samples to be tested. The results of analyzing the sample to be tested by using the spiral molecularly imprinted open tubular column prepared in example 1 and the liquid-liquid extraction method recommended by the national standard method are shown in fig. 8 and 9 (the abscissa is retention time and the ordinate is peak height), in each of the graphs, the upper curve is the curve corresponding to the extraction method of the spiral molecularly imprinted open tubular column, the lower curve is the curve corresponding to the liquid-liquid extraction method, and MeP represents methyl p-hydroxybenzoate
EtP for ethyl p-hydroxybenzoate, IPrP for isopropyl p-hydroxybenzoate, PrP for propyl p-hydroxybenzoate, IBuP for butyl p-hydroxybenzoate, BuP for isobutyl p-hydroxybenzoate.
As can be seen from fig. 8 and 9, compared with the liquid-liquid extraction method used in the conventional standard, the molecularly imprinted open tubular column provided by the present invention has a good separation and purification effect on the complex sample, can realize selective extraction of the target substance in the complex sample, and significantly reduces sample matrix interference.
Further, four parts of the above bath lotion were prepared, each 10g of which was added with methyl paraben (0ug/g, 6ug/g, 20ug/g, 60ug/g) at different concentrations. The eight groups of samples were subjected to the labeling recovery test using the molecularly imprinted open tubular columns prepared in the examples, the molecularly imprinted polymer prepared in comparative example 1, and the molecularly imprinted open tubular column prepared in comparative example 3, for 7 times. The test results are shown in table 2.
TABLE 2 recovery test
As can be seen from table 2 above, compared with the comparative examples, each example shows a better recovery rate, and still shows a better extraction efficiency after the molecular imprinting open tubular column is repeatedly used for 7 times, which indicates that the molecular imprinting open tubular column provided by the present invention can be used for the pretreatment and detection analysis of parabens in a personal care product sample, and has high recycling rate and a better application prospect.
The above is only a preferred embodiment of the present invention, and it is not intended to limit the scope of the invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall be included in the scope of the present invention.
Claims (10)
1. A preparation method of a molecular imprinting open tubular column is characterized by comprising the following steps:
preparing a molecularly imprinted polymer by using p-hydroxybenzoate as a template molecule, and modifying an epoxy group of the molecularly imprinted polymer to obtain an epoxy-modified molecularly imprinted polymer;
performing amino modification on the surface of the capillary to obtain an amino-modified capillary column;
dispersing the epoxy modified molecularly imprinted polymer in ethanol to form a mixed solution;
and injecting the mixed solution into the amino modified capillary column, sealing, and polymerizing to crosslink amino and epoxy groups to form the molecularly imprinted open tubular column.
2. The method for preparing a molecularly imprinted open tubular column according to claim 1, wherein the step of preparing a molecularly imprinted polymer by using p-hydroxybenzoate as a template molecule and modifying the molecularly imprinted polymer with an epoxy group to obtain the epoxy-modified molecularly imprinted polymer comprises:
adding p-hydroxybenzoate and a functional monomer into an organic solvent to form a pre-polymerization solution;
adding a cross-linking agent and an initiator into the prepolymerization solution, introducing nitrogen to remove oxygen, and carrying out polymerization reaction at 50-80 ℃ to form a primary reaction solution;
adding a toluene solution of glycidyl methacrylate into the primary reaction solution, reacting for 4-10 h, and washing away template molecules to obtain an epoxy modified molecularly imprinted polymer;
wherein the molar ratio of the p-hydroxybenzoate ester to the cross-linking agent to the functional monomer is (5-50): (1-10): 1.
3. the method for preparing a molecularly imprinted open tubular column according to claim 2, wherein the step of adding the paraben and the functional monomer, which is one or both of methacrylic acid and isobutyl vinyl ether, to the organic solvent to form a prepolymerization solution.
4. The method for preparing the molecularly imprinted open tubular column according to claim 2, wherein the step of adding a toluene solution of glycidyl methacrylate into the primary reaction solution, reacting for 4-10 hours, and washing away the template molecule to obtain the epoxy-modified molecularly imprinted polymer comprises: and after the polymerization reaction is carried out for at least 8 hours, supplementing the initiator into the primary reaction liquid, then sequentially adding a toluene solution of glycidyl methacrylate and the initiator, reacting for 4-10 hours, and washing away template molecules to obtain the epoxy modified molecularly imprinted polymer.
5. The method for preparing a molecularly imprinted open tubular column according to claim 2, wherein in the step of adding a toluene solution of glycidyl methacrylate into the primary reaction solution, reacting for 4-10 hours, and washing away the template molecules to obtain the epoxy-modified molecularly imprinted polymer, the mass concentration of glycidyl methacrylate in the toluene solution of glycidyl methacrylate is not more than 10 (w/w)%.
6. The method for preparing a molecularly imprinted open tubular column according to claim 1, wherein in the step of performing amino modification on the surface of the capillary tube to obtain the amino-modified capillary column, the capillary tube is a polytetrafluoroethylene capillary tube; and/or the presence of a gas in the gas,
the diameter of the capillary is not more than 30 μm.
7. The method for preparing a molecularly imprinted open tubular column according to claim 1, wherein the step of performing amino modification on the surface of the capillary to obtain an amino-modified capillary column comprises:
injecting an alkaline solution of dopamine into the pretreated capillary tube to obtain the capillary tube with the inner wall modified with hydroxyl groups;
injecting an ethanol solution of 3-glycidyl ether oxypropyl methyl diethoxysilane into the capillary tube with the inner wall modified with the hydroxyl groups, sealing the tube opening, and standing for 5-12 h to obtain a primary capillary tube;
and (3) washing the primary capillary tube until no solvent is left, injecting an ethanol solution of polyethyleneimine into the primary capillary tube, sealing the tube opening, and standing for 10-24 hours to obtain the amino modified capillary tube column.
8. The method for preparing a molecularly imprinted open tubular column according to claim 7, wherein the step of injecting an ethanol solution of 3-glycidyl ether oxypropyl methyldiethoxysilane into the capillary tube with the inner wall modified with hydroxyl groups, sealing the tube orifice, standing for 5-12 hours to obtain a primary capillary tube,
the volume concentration of the 3-glycidyloxypropylmethyldiethoxysilane in the ethanol solution of the 3-glycidyloxypropylmethyldiethoxysilane is 5 to 40 (v/v)%.
9. The method for preparing a molecularly imprinted open tubular column according to claim 7, wherein in the step of washing the primary capillary until no solvent remains, injecting an ethanol solution of polyethyleneimine into the primary capillary, sealing the orifice, standing for 10-24 h to obtain the amino-modified capillary column,
the volume concentration of the polyethyleneimine in the polyethyleneimine ethanol solution is 5-30 (v/v)%.
10. The method for preparing a molecularly imprinted open tubular column according to claim 1, wherein the step of injecting the mixed solution into the amino-modified capillary column, sealing, and polymerizing to form the molecularly imprinted open tubular column further comprises: and carrying out molecular imprinting open pipe column molding treatment to form a spiral molecular imprinting open pipe column.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910649163.5A CN110302562B (en) | 2019-07-17 | 2019-07-17 | Preparation method of molecular imprinting open tubular column |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910649163.5A CN110302562B (en) | 2019-07-17 | 2019-07-17 | Preparation method of molecular imprinting open tubular column |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110302562A CN110302562A (en) | 2019-10-08 |
| CN110302562B true CN110302562B (en) | 2021-08-27 |
Family
ID=68081122
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910649163.5A Active CN110302562B (en) | 2019-07-17 | 2019-07-17 | Preparation method of molecular imprinting open tubular column |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110302562B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111203001B (en) * | 2020-02-18 | 2021-04-02 | 武汉大学 | Preparation method of novel fluorine-functionalized open-tube capillary chromatographic column |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102068833A (en) * | 2010-10-27 | 2011-05-25 | 福州大学 | Polyamine modified antenna type polymer capillary electrochromatography open tubular column and preparation method thereof |
| CN103191705A (en) * | 2013-04-15 | 2013-07-10 | 武汉大学 | Preparation method of open tubular capillary electrochromatographic column |
| CN103611511A (en) * | 2013-12-02 | 2014-03-05 | 武汉大学 | Preparation method for grapheme open-tube electric chromatographic column |
| CN105214340A (en) * | 2015-09-14 | 2016-01-06 | 武汉长林医药科技有限公司 | A kind of method of fixing covalent organic framework material and application thereof |
| CN108744592A (en) * | 2018-05-28 | 2018-11-06 | 福州大学 | A kind of preparation method of cyclo-dextrin-modified POSS-PEI organic silica gels hydridization integral post |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060113231A1 (en) * | 2000-10-23 | 2006-06-01 | Abdul Malik | Sample pre-concentration tubes with sol-gel surface coatings and/or sol-gel monolithic beds |
-
2019
- 2019-07-17 CN CN201910649163.5A patent/CN110302562B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102068833A (en) * | 2010-10-27 | 2011-05-25 | 福州大学 | Polyamine modified antenna type polymer capillary electrochromatography open tubular column and preparation method thereof |
| CN103191705A (en) * | 2013-04-15 | 2013-07-10 | 武汉大学 | Preparation method of open tubular capillary electrochromatographic column |
| CN103611511A (en) * | 2013-12-02 | 2014-03-05 | 武汉大学 | Preparation method for grapheme open-tube electric chromatographic column |
| CN105214340A (en) * | 2015-09-14 | 2016-01-06 | 武汉长林医药科技有限公司 | A kind of method of fixing covalent organic framework material and application thereof |
| CN108744592A (en) * | 2018-05-28 | 2018-11-06 | 福州大学 | A kind of preparation method of cyclo-dextrin-modified POSS-PEI organic silica gels hydridization integral post |
Non-Patent Citations (2)
| Title |
|---|
| 化学键合聚乙烯亚胺涂层毛细管柱的快速制备及评价;陈卓铃等;《分析化学》;20061231;第34卷;214-216 * |
| 对羟基苯甲酸乙酯印迹聚合物固相微萃取制备及条件优化;陈思等;《化学世界》;20121231(第04期);219-222 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110302562A (en) | 2019-10-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Díaz-Álvarez et al. | Molecularly imprinted polymer monolith containing magnetic nanoparticles for the stir-bar sorptive extraction of thiabendazole and carbendazim from orange samples | |
| Xu et al. | Investigation of ractopamine molecularly imprinted stir bar sorptive extraction and its application for trace analysis of β2-agonists in complex samples | |
| Wang et al. | Magnetic molecularly imprinted nanoparticles based on dendritic-grafting modification for determination of estrogens in plasma samples | |
| Ansari et al. | A multi-walled carbon nanotube-based magnetic molecularly imprinted polymer as a highly selective sorbent for ultrasonic-assisted dispersive solid-phase microextraction of sotalol in biological fluids | |
| CN105498694B (en) | The metallic organic framework magnetic material of a kind of temperature sensitive polymer parcel and application thereof | |
| CN102169109B (en) | Method for preparing estrogen substitution template molecular imprinting solid phase micro extraction head | |
| CN110302562B (en) | Preparation method of molecular imprinting open tubular column | |
| CN107552016A (en) | A kind of preparation method and applications of cysteine-modifying Organic Polymer Monolithic Columns | |
| CN110361462B (en) | Molecular engram tube tip micro-extraction head and preparation method thereof | |
| CN111632583A (en) | Preparation method and application of hydrophilic tetracycline molecular imprinting solid-phase microextraction fiber | |
| Yang et al. | Porous capillary monolithic column coupled with ultrahigh performance liquid chromatography-tandem mass spectrometry for fast and effective separation and determination of estrogens | |
| CN115926046B (en) | Catalpol magnetic surface molecularly imprinted polymer and preparation method and application thereof | |
| CN110694601A (en) | Solid phase micro-extraction head and preparation method and application thereof | |
| CN112337441B (en) | Phenylboronic acid-chitosan modified monolithic column and preparation method and application thereof | |
| CN103599755A (en) | Phenylethanolamine A molecularly imprinted membrane, preparation method thereof and applications thereof | |
| Zhang et al. | Selective microextraction of carbaryl and naproxen using organic–inorganic monolithic columns containing a double molecular imprint | |
| CN108435138A (en) | The solid-phase micro-extracting device prepared using the N that MOFs the is precursor synthesis carbon nanotube coatings adulterated and application | |
| CN109839452B (en) | Molecular imprinting stirring rod and preparation method and application thereof | |
| CN109771988B (en) | Diethyl phthalate solid-phase micro-extraction method based on molecular imprinting technology | |
| Zafarghandi et al. | Preparation of pH‐Sensitive Molecularly Imprinted Polymer via Dual‐Monomer for Selective Solid‐Phase Extraction of Ribavirin from Human Urine and Pharmaceutical Samples | |
| CN111574666A (en) | Compound extraction plate and preparation method and application thereof | |
| CN115980221A (en) | Method for detecting concentration of trace drug in biological sample based on molecular imprinting-HPLC (high performance liquid chromatography) combined detection | |
| CN110423302A (en) | A kind of magnetic surface molecularly imprinted polymer and the preparation method and application thereof | |
| CN111892681B (en) | Preparation method and application of modified polymer microsphere adsorbent | |
| CN212134597U (en) | Molecular imprinting plate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |