CN112666272A - pCEC-SERS combined on-line analysis and detection method based on monolithic column - Google Patents
pCEC-SERS combined on-line analysis and detection method based on monolithic column Download PDFInfo
- Publication number
- CN112666272A CN112666272A CN202011307808.6A CN202011307808A CN112666272A CN 112666272 A CN112666272 A CN 112666272A CN 202011307808 A CN202011307808 A CN 202011307808A CN 112666272 A CN112666272 A CN 112666272A
- Authority
- CN
- China
- Prior art keywords
- column
- sers
- monolithic
- monolithic column
- pcec
- 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.)
- Pending
Links
- 238000001514 detection method Methods 0.000 title claims abstract description 65
- 238000004416 surface enhanced Raman spectroscopy Methods 0.000 title claims abstract description 65
- 238000004458 analytical method Methods 0.000 title claims abstract description 38
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 31
- 239000010931 gold Substances 0.000 claims abstract description 30
- 229910052737 gold Inorganic materials 0.000 claims abstract description 30
- 239000003153 chemical reaction reagent Substances 0.000 claims abstract description 21
- 238000006116 polymerization reaction Methods 0.000 claims abstract description 19
- 239000000741 silica gel Substances 0.000 claims abstract description 19
- 229910002027 silica gel Inorganic materials 0.000 claims abstract description 19
- 238000002444 silanisation Methods 0.000 claims abstract description 18
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims abstract description 16
- 238000000034 method Methods 0.000 claims abstract description 15
- 239000000463 material Substances 0.000 claims abstract description 12
- 238000000926 separation method Methods 0.000 claims abstract description 12
- 239000000758 substrate Substances 0.000 claims abstract description 12
- 238000006243 chemical reaction Methods 0.000 claims abstract description 11
- 238000001069 Raman spectroscopy Methods 0.000 claims abstract description 10
- 238000002045 capillary electrochromatography Methods 0.000 claims abstract description 9
- 238000005516 engineering process Methods 0.000 claims abstract description 8
- 239000001509 sodium citrate Substances 0.000 claims abstract description 8
- NLJMYIDDQXHKNR-UHFFFAOYSA-K sodium citrate Chemical compound O.O.[Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O NLJMYIDDQXHKNR-UHFFFAOYSA-K 0.000 claims abstract description 8
- 239000007788 liquid Substances 0.000 claims abstract description 7
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 claims abstract description 7
- 239000000126 substance Substances 0.000 claims abstract description 7
- 150000002500 ions Chemical class 0.000 claims abstract description 6
- 230000000694 effects Effects 0.000 claims abstract description 5
- 238000006068 polycondensation reaction Methods 0.000 claims abstract description 5
- 230000009467 reduction Effects 0.000 claims abstract description 5
- 239000002243 precursor Substances 0.000 claims abstract description 4
- 238000005034 decoration Methods 0.000 claims abstract description 3
- 238000011065 in-situ storage Methods 0.000 claims abstract description 3
- 238000003980 solgel method Methods 0.000 claims abstract description 3
- 239000000243 solution Substances 0.000 claims description 44
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 24
- 239000002245 particle Substances 0.000 claims description 19
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 17
- 239000010453 quartz Substances 0.000 claims description 12
- LZZYPRNAOMGNLH-UHFFFAOYSA-M Cetrimonium bromide Chemical compound [Br-].CCCCCCCCCCCCCCCC[N+](C)(C)C LZZYPRNAOMGNLH-UHFFFAOYSA-M 0.000 claims description 10
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 claims description 10
- 239000003795 chemical substances by application Substances 0.000 claims description 9
- 238000005370 electroosmosis Methods 0.000 claims description 8
- 239000002105 nanoparticle Substances 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 7
- 239000000178 monomer Substances 0.000 claims description 7
- 239000007864 aqueous solution Substances 0.000 claims description 6
- 238000009835 boiling Methods 0.000 claims description 6
- 239000011521 glass Substances 0.000 claims description 6
- INJVFBCDVXYHGQ-UHFFFAOYSA-N n'-(3-triethoxysilylpropyl)ethane-1,2-diamine Chemical compound CCO[Si](OCC)(OCC)CCCNCCN INJVFBCDVXYHGQ-UHFFFAOYSA-N 0.000 claims description 6
- 238000005303 weighing Methods 0.000 claims description 6
- 238000001035 drying Methods 0.000 claims description 5
- 239000012530 fluid Substances 0.000 claims description 5
- 238000009210 therapy by ultrasound Methods 0.000 claims description 5
- 238000009825 accumulation Methods 0.000 claims description 4
- 239000002253 acid Substances 0.000 claims description 3
- 239000012491 analyte Substances 0.000 claims description 3
- 239000000084 colloidal system Substances 0.000 claims description 3
- 238000001816 cooling Methods 0.000 claims description 3
- 229920001971 elastomer Polymers 0.000 claims description 3
- 235000019441 ethanol Nutrition 0.000 claims description 3
- 238000001802 infusion Methods 0.000 claims description 3
- 230000010355 oscillation Effects 0.000 claims description 3
- 238000007789 sealing Methods 0.000 claims description 3
- 239000002904 solvent Substances 0.000 claims description 3
- 238000005406 washing Methods 0.000 claims description 3
- 239000012528 membrane Substances 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 238000001179 sorption measurement Methods 0.000 claims description 2
- 229910021642 ultra pure water Inorganic materials 0.000 claims description 2
- 239000012498 ultrapure water Substances 0.000 claims description 2
- 229920001730 Moisture cure polyurethane Polymers 0.000 claims 1
- 230000005284 excitation Effects 0.000 claims 1
- 238000009472 formulation Methods 0.000 claims 1
- 239000011148 porous material Substances 0.000 claims 1
- 238000010206 sensitivity analysis Methods 0.000 abstract description 2
- 239000000523 sample Substances 0.000 description 12
- 238000012876 topography Methods 0.000 description 5
- FHTDDANQIMVWKZ-UHFFFAOYSA-N 1h-pyridine-4-thione Chemical compound SC1=CC=NC=C1 FHTDDANQIMVWKZ-UHFFFAOYSA-N 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 4
- 238000011010 flushing procedure Methods 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000005684 electric field Effects 0.000 description 3
- 230000007935 neutral effect Effects 0.000 description 3
- 239000012071 phase Substances 0.000 description 3
- 230000035945 sensitivity Effects 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 239000000499 gel Substances 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 238000004949 mass spectrometry Methods 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 238000000479 surface-enhanced Raman spectrum Methods 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 238000003556 assay Methods 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000013375 chromatographic separation Methods 0.000 description 1
- 238000004587 chromatography analysis Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000007872 degassing Methods 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010828 elution Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000004088 foaming agent Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000005457 ice water Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000004255 ion exchange chromatography Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000005580 one pot reaction Methods 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 239000010452 phosphate Substances 0.000 description 1
- 239000008363 phosphate buffer Substances 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000011896 sensitive detection Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
Images
Landscapes
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
Abstract
The invention provides a pCEC-SERS combined on-line analysis and detection method based on an integral column, which comprises the following steps: monolithic column, in-situ polymerization and inert pore-making technology are applied, silanization reagent polymerization liquid is used as reaction precursor, and simple and quick sol-gel method and thermal polycondensation reaction are adopted to form NH with positive charge ions in capillary column3 +The polymeric monolith column of (1); preparing a negative charge nano gold colloid solution by adopting a sodium citrate reduction method; the device is arranged at one end of an integral column and used for decorating negative charge nanogold, a polyamino-nanogold silica gel hybrid integral column is prepared through column decoration, two sections of integral column materials with different charges are formed, and one end of an amino section of the integral column is connected with a capillary electrochromatography for enrichment and separation of a substance to be detected; the SERS active substrate refers to one end of the whole column modified with the nano-gold, and laser of the Raman spectrometer is focused on the whole column and is perpendicular to the radial direction of the whole column. The invention has the effect of realizing the rapid and high-sensitivity analysis and detection of trace analytes to be detected in complex samples.
Description
Technical Field
The invention relates to the technical field of analytical chemistry, in particular to a pCEC-SERS combined on-line analysis and detection method based on an integral column.
Background
In recent years, with the development of material science and analytical techniques, the separation and detection of trace or trace substances in a sample with a complex matrix background, or even the high-sensitivity detection on a monomolecular level, has become a leading issue in the field of analytical science. At present, the detection method of trace or ultra-trace analytes mainly adopts chromatography and chromatography-mass spectrometry combined detection, however, because the concentration of trace analytes is low, the detection sensitivity must be improved by means of an extraction enrichment mode, the consumption of traditional solid phase column extraction enrichment samples is large, and the measurement requirements are difficult to meet. And mass spectrometry has the limitations of expensive instrument and equipment, high detection cost, complex operation process, long detection time consumption, and the need of professional staff for operation and maintenance. Therefore, it is urgently needed to develop a rapid, high-sensitivity, simple and convenient micro-nano analysis technology to realize accurate research on trace analytes.
The pressurized capillary electrochromatography (pCEC) is a micro-nano separation technology taking electroosmotic flow and auxiliary pump pressure as comprehensive driving forces, takes a functionalized monolithic column as a medium, has high column efficiency, large compatible amount and less reagent consumption, has the synergistic effect of accumulated sample introduction and enrichment and electric field accumulation of a liquid chromatographic column, and has great potential for the online selective enrichment of trace substances.
The Surface Enhanced Raman Scattering (SERS) technology can realize high-sensitivity detection at a single molecular level, and provides a powerful means for online detection of trace analytes. As the SERS substrate, the whole column has a highly cross-linked porous 3D structure, so that the 'hot point' generated by the nano particles is facilitated, and the detection sensitivity is high. At present, no relevant report is found in the construction of a trace analyte monolithic column pCEC-SERS combined analysis technology integrating sample selective enrichment, electric field assisted separation and online label-free sensitive detection.
In view of the above, the present inventors have devised a specific structure, and have made this disclosure.
Disclosure of Invention
In order to solve the problems, the technical scheme of the invention is as follows:
the method adopts a silanization reagent as a precursor raw material reagent of a sol-gel reaction, and forms ions NH with positive charges in a capillary column based on a simple and quick one-pot method and thermal polycondensation reaction3 +The polymeric monolithic column is characterized in that negative charge nanogold colloidal solution is modified at one end of the monolithic column to prepare a polyamino-nanogold silica gel hybrid monolithic column, two sections of monolithic column materials with different charges are formed, the unmodified nanogold end of the monolithic column is connected with a capillary electrochromatography, the modified nanogold end is used as an SERS active substrate, and laser of a Raman spectrometer is aligned to the monolithic column and is perpendicular to the radial direction of the monolithic column to perform detection. The method is characterized in that a functionalized monolithic column integrating ion chromatography, selective enrichment and SERS substrate is prepared, and a pCEC-SERS combined online analysis and detection method for nano-scale sample injection is established, so that the method has the effect of realizing rapid and high-sensitivity analysis and detection of trace analytes to be detected.
An on-line analysis and detection method for pCEC-SERS combination based on an integral column comprises the following steps:
monolithic column, in-situ polymerization and inert pore-making technology are applied, silanization reagent polymerization liquid is used as reaction precursor, and simple and quick sol-gel method and thermal polycondensation reaction are adopted to form NH with positive charge ions in capillary column3 +The polymeric monolith column of (1);
preparing a negative charge nano gold colloid solution by adopting a sodium citrate reduction method; the device is arranged at one end of an integral column and used for decorating negative charge nanogold, a polyamino-nanogold silica gel hybrid integral column is prepared through column decoration, two sections of integral column materials with different charges are formed, and one end of an amino section of the integral column is connected with a capillary electrochromatography for enrichment and separation of a substance to be detected;
the SERS active substrate refers to one end of the whole column modified with the nano-gold, and laser of the Raman spectrometer is focused on the whole column and is perpendicular to the radial direction of the whole column.
Further setting the following steps: the formula of the silanization reagent polymerization solution contains a ternary pore-foaming agent consisting of a silanization reagent, Cetyl Trimethyl Ammonium Bromide (CTAB), water and absolute ethyl alcohol.
Further setting the following steps: the formula of the silanization reagent contains Tetraethoxysilane (TEOS) and N- (beta-aminoethyl) -gamma-aminopropyltriethoxysilane (AEAPTES).
Further setting the following steps: the silanization reagent polymerization solution is calculated by 100 percent of the sum of the mass percentages, and the mass percentages of the components are as follows: 41.08% of tetraethoxysilane, 10.68% of N- (beta-aminoethyl) -gamma-aminopropyltriethoxysilane, 2.44% of hexadecyltrimethylammonium bromide, 11.01% of water and 34.79% of absolute ethyl alcohol.
Further setting the following steps: the modified nano-gold on the monolithic column is characterized in that nano-gold particles are uniformly distributed on the surface of a monolithic column polymerization column bed through stronger adsorption between amino and gold; the gold nanoparticles are prepared by a sodium citrate reduction method, the surfaces of the gold nanoparticles have negative charges, and the particle size of the gold nanoparticles is 50nm to 60 nm.
Further setting the following steps: the capillary is a quartz capillary with far ultraviolet optics, ultraviolet optics or infrared optics, and the inner diameter of the quartz capillary is 100 mu m.
Further setting the following steps: the water in the component of the silanization reagent polymerization solution is ultrapure water, the resistivity is 18.25 MOmega, and the water is filtered by a filter membrane with the aperture of 0.22 mu M.
Further setting the following steps: the integral column SERS detection window is perpendicular to the exciting light direction of the Raman spectrometer, and an SERS signal of the trace analyte is obtained by adjusting the position of the focal length in the integral capillary column with the SERS effect.
Further setting the following steps: the two sections of silica gel hybrid monolithic columns with different charges respectively form different directions of electroosmotic flow on two sides of an interface, fluid pressure-reverse electroosmotic flow constant speed accumulation and chromatographic enrichment of functional matrixes are applied to the front section of the interface, rapid enrichment and separation of samples are realized, fluid pressure-forward electroosmotic flow is applied to the rear section (detection end), carrier liquid is driven to elute and analyze substances to be detected, and high-sensitivity detection is performed on the whole column SERS.
The pCEC-SERS combined online analysis and detection method based on the monolithic column comprises the following detection steps:
s1: preparing a polyamino silica gel hybrid monolithic column:
weighing the ternary pore-forming agent CTAB, water and absolute ethyl alcohol in proportion into a 5mL glass bottle, carrying out vortex oscillation to form a uniform solution, placing the uniform solution in a 0 ℃ ice bath ultrasonic treatment for 5min, weighing the monomers TEOS and AEAPTES in proportion into the glass bottle containing the ternary pore-forming agent solution, and carrying out 0 ℃ ice bath ultrasonic treatment for 30s to form a uniform pre-polymerization solution. And (3) injecting the prepolymer solution into the pretreated quartz capillary, sealing two ends of the quartz capillary by using rubber pads, placing the quartz capillary in a water bath at 40 ℃ for constant-temperature reaction for 24 hours, taking out the capillary column, cutting off a small part of two ends of the capillary column, placing the capillary column in a drying oven at 120 ℃ for heating for 3 hours, and removing ethanol, unreacted silica gel monomers and dried colloid. Washing the monolithic column with high pressure solvent pump after drying to remove unreacted residue to obtain NH with surface rich in positive charge ions3 +The polyamino silica gel hybrid monolithic column;
s2: preparing nano gold particles:
heating 200mL of tetrachloroauric acid aqueous solution with the mass fraction of 0.01% to boiling, quickly adding 1.4mL of sodium citrate aqueous solution with the mass fraction of 1%, changing the color of the solution from light yellow to black after about 1min, changing the solution into brownish red after 2-3 min, continuously keeping slight boiling for 40min, stopping reaction, cooling in water bath, and preparing nano-gold particle colloidal solution with the particle size of about 55 nm;
s3: preparing two sections of block monolithic column polymeric materials with different charges respectively:
introducing the nano-gold colloidal solution obtained in the step S2 into a polyamino silica gel hybrid monolithic column through a high-pressure infusion pump, and modifying negatively charged nano-gold particles at one end of the monolithic column so as to uniformly distribute the negatively charged nano-gold particles at one end of the monolithic column to form two sections of monolithic column materials with different charges respectively;
s4: the pCEC-SERS combined on-line analysis and detection method based on the monolithic column comprises the following steps:
one end of an amino section of two segmented integral columns with different charges is connected with a capillary electrochromatography for enrichment and separation of an object to be detected, the integral column modifies a nanogold section to be used as an SERS active substrate, and laser of a Raman spectrometer is focused on the integral column and is perpendicular to the radial direction of the integral column for detection.
After adopting the technical scheme, compared with the background technology, the invention has the following advantages:
1. the invention is based on silanization reagent polymerization liquid, and adopts simple and rapid 'sol-gel' method and thermal polycondensation reaction to form NH with positive charge ions in a capillary column3 +The negative charge nano gold colloid solution is modified at one end of the monolithic column, so that two monolithic column materials with different charges are prepared and formed; opposite charge ions are introduced into the same capillary tube monolithic column, the interface electric field charge regulation is realized by regulating and controlling the mobile phase composition and pH, fluid pressure-reverse electroosmotic flow constant-speed accumulation and the chromatographic enrichment and elution of functional matrix are comprehensively applied, the rapid enrichment mode and separation of a sample are realized, and the technical bottleneck that the sample is large in consumption, long in consumed time and low in efficiency in the traditional chromatographic enrichment is solved;
2. the integral column is used as the SERS active substrate, continuous collection of SERS spectra under the dynamic flow condition can be realized, the SERS detection repeatability and detection efficiency are improved, and the problem that the repeatability and the detection efficiency are difficult to compromise in the traditional SERS detection is solved. Moreover, the monolithic column has a highly cross-linked porous 3D structure, so that the nanoparticle is favorable for generating hot spots, and the detection sensitivity is improved;
3. the pCEC-SERS combined analysis and detection method based on the monolithic column integrates chromatographic separation, selective enrichment and an SERS substrate, realizes nano-scale sample introduction, and can be used for on-line selective high-efficiency enrichment and high-sensitivity label-free continuous analysis and detection of trace analytes in complex samples.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.
Wherein:
FIG. 1 is a schematic diagram of an on-line analysis and detection of a pCEC-SERS combination based on an integral column.
FIG. 2 is an electron microscope topography of a polyamino hybrid monolithic column prepared in the pCEC-SERS combined on-line analysis and detection method based on the monolithic column.
FIG. 3 is a transmission electron microscope image of nanogold prepared in the pCEC-SERS combined online analysis and detection method based on an integral column;
FIG. 4 is a SERS spectrogram for detecting 4-mercaptopyridine with different concentrations by using a pCEC-SERS combination on-line analysis based on an integral column.
FIG. 5 is a schematic diagram of stability of the pCEC-SERS combined on-line analysis and detection method based on the monolithic column, i.e. 10 continuous 40-time collection-7SERS spectrogram of mol/L4-mercaptopyridine.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention clearer and clearer, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example (b):
an on-line analysis and detection method for pCEC-SERS coupling based on an integral column comprises the following steps:
1. preparing a polyamino silica gel hybrid monolithic column:
(1) weighing the ternary pore-forming agent in a 5mL glass bottle, carrying out vortex oscillation to form a uniform solution, carrying out ultrasonic treatment in an ice water bath at 0 ℃ for 5min, weighing the monomer silanization reagent and the polyaminosilane reagent in proportion in the glass bottle containing the ternary pore-forming agent solution, and carrying out ultrasonic degassing in an ice bath at 0 ℃ for 30s to form a uniform pre-polymerization solution;
specifically, in the step, the ternary pore-making agent is cetyl trimethyl ammonium bromide, water and absolute ethyl alcohol respectively; the monomer silanization reagent can be tetraethoxysilane; the polyamino silanization reagent is N- (beta-aminoethyl) -gamma-aminopropyl triethoxysilane;
in the step, the dosage of the components of the ternary pore-forming agent is calculated by 100 percent of the sum of the mass percentages, namely, 41.08 percent of tetraethoxysilane, 10.68 percent of N- (beta-aminoethyl) -gamma-aminopropyltriethoxysilane, 2.44 percent of hexadecyl trimethyl ammonium bromide, 11.01 percent of water and 34.79 percent of absolute ethyl alcohol;
(2) injecting the pre-polymerization solution into a pretreated quartz capillary tube (the specification of the capillary tube is 100 mu m i.d.. times.360 mu m o.d.), sealing two ends of the capillary tube by using a rubber pad, placing the capillary tube in a water bath at 40 ℃ for constant-temperature reaction for 24 hours, taking out a capillary tube integral column, cutting off a small part of two ends of the capillary tube integral column after the reaction, placing the capillary tube integral column in a drying oven at 120 ℃ for continuous heating for 3 hours, and removing ethanol, unreacted silica gel monomers and dry colloids. Washing the monolithic column with high pressure solvent pump after drying to remove unreacted residue to obtain NH with surface rich in positive charge ions3 +The polyamino silica gel hybrid monolithic column;
specifically, in this step, the specific process of capillary column pretreatment comprises the following steps:
intercepting a certain length of a quartz capillary tube, sequentially flushing for 0.5h by using 0.1mol/L HCl solution, removing impurities on the surface of the capillary tube, leading the capillary tube to be neutral (pH is 7.00) by using deionized water, flushing for 12h by using 1.0mol/L NaOH solution, etching the surface of the quartz capillary tube to expose silicon hydroxyl groups, leading secondary water to be neutral (pH is 7.00), flushing for 12h by using 1.0mol/L HCl solution, leading the secondary water to be neutral (pH is 7.00), finally flushing for 30min by using methanol solution, placing the quartz capillary tube in a 180 ℃ gas chromatograph heating furnace, and purging an empty capillary column for 3h by using nitrogen for later use.
2. Preparing nano gold particles:
heating 200mL of tetrachloroauric acid aqueous solution with the mass fraction of 0.01% to boiling, quickly adding 1.4mL of sodium citrate aqueous solution with the mass fraction of 1%, changing the color of the solution from light yellow to black after about 1min, changing the solution into brownish red after 2-3 min, continuously keeping slight boiling for 40min, stopping reaction, cooling in water bath, and preparing the nano-gold particle colloidal solution with the particle size of about 55 nm.
3. Preparing two sections of block monolithic column polymeric materials with different charges respectively:
introducing the obtained nano-gold colloidal solution into a polyamino silica gel hybrid monolithic column through a high-pressure infusion pump, and modifying negatively charged nano-gold particles on the column at one end of the monolithic column so as to uniformly distribute the negatively charged nano-gold particles at one end of the monolithic column, thereby forming two sections of monolithic column materials with different charges respectively for later use;
4. pCEC-SERS combined on-line analysis and detection method based on monolithic column
Connecting one end of the obtained two-section block monolithic column with different charges respectively with a capillary electrochromatography for enrichment and separation of an object to be detected, using one end of the monolithic column modified with the nano-gold as an SERS active substrate, and aligning laser of the Raman spectrometer to the monolithic column and detecting the laser in a direction perpendicular to the radial direction of the capillary.
FIG. 1 shows a schematic diagram of the detection method of pCEC-SERS on-line analysis based on monolithic column provided by the invention; FIG. 2 shows an exemplary electron microscope topography of the polyamino hybrid monolithic column of the pCEC-SERS combined on-line analysis and detection method based on the monolithic column, and as can be seen from the scanning electron microscope topography, the prepared polyamino silica gel hybrid monolithic column has the advantages of complete and uniform column body structure, tight combination of the filler and the column wall, and stable column structure. FIG. 3 shows a transmission electron microscope topography of an example of the nanogold based on the monolithic column pCEC-SERS combined online analysis detection method, wherein the transmission electron microscope topography is respectively shown in the A and B with the magnification of 40k times and 80k times, and the nanogold transmission electron microscope shows that the prepared nanogold is uniformly dispersed and has a uniform size, and the size of the nanogold is about 55 nm.
The detection method provided by the invention is applied to the on-line analysis, detection and analysis process of 4-mercaptopyridine, and comprises the steps of on-line machine balance, sample introduction and SERS detection on an integral column, wherein the detection and analysis process is shown as a figure 1, and the detection and analysis method comprises the following specific steps:
(1) and (3) balancing on the whole column: connecting one end of the unmodified nano-gold of the monolithic column with a capillary electrochromatography, adopting 10mM phosphate buffer (pH 6.5) solution as a balance mobile phase, wherein the balance backpressure is a 1000psi backpressure valve, the flow rate is 0.10mL/min, and the balance time is 0.5 h;
(2) sample introduction: injecting sample by using a six-way valve, wherein the sample injection amount is 20 mu L;
(3)SERS detection: the laser of the Raman spectrometer is aligned with the whole column modified nano-gold section and is vertical to the radial direction of the capillary, and the height of the carrying table is adjusted, so that the laser is focused at the position with the strongest SERS signal in the whole column. The mobile phase was 10mM phosphate buffered (pH 6.5) solution, the assay back pressure was 1000psi back pressure valve, flow rate 0.10mL/min, voltage 0 kV. FIG. 4 is a SERS spectrogram of 4-mercaptopyridine with different concentrations, and it can be seen from the graph that as the concentration of 4-mercaptopyridine decreases, the SERS signal gradually decreases, and the concentration is 10-8The SERS signal of mol/L4-mercaptopyridine is clear and distinguishable. In order to further verify the stability of the pCEC-SERS combined on-line detection method of the monolithic column, 10 percent of the total mass is adopted-7The mol/L4-mercaptopyridine is used as a probe molecule to carry out continuous acquisition for 40 times, the SERS spectrogram is shown in figure 5, the visible SERS signal is very uniform and is 1091cm-1The Relative Standard Deviation (RSD) of the intensity of the SERS spectrum peak is 2.20%, which shows that the stability is better.
The invention has been described above with reference to the accompanying drawings, it is obvious that the invention is not limited to the specific implementation in the above-described manner, and it is within the scope of the invention to apply the inventive concept and solution to other applications without substantial modification.
Claims (10)
1. An on-line analysis and detection method for pCEC-SERS combination based on an integral column is characterized by comprising the following steps:
monolithic column, in-situ polymerization and inert pore-making technology are applied, silanization reagent polymerization liquid is used as reaction precursor, and simple and quick sol-gel method and thermal polycondensation reaction are adopted to form NH with positive charge ions in capillary column3 +The polymeric monolith column of (1);
preparing a negative charge nano gold colloid solution by adopting a sodium citrate reduction method; the device is arranged at one end of an integral column and used for decorating negative charge nanogold, a polyamino-nanogold silica gel hybrid integral column is prepared through column decoration, two sections of integral column materials with different charges are formed, and one end of an amino section of the integral column is connected with a capillary electrochromatography for enrichment and separation of a substance to be detected;
the SERS active substrate refers to one end of the whole column modified with the nano-gold, and laser of the Raman spectrometer is focused on the whole column and is perpendicular to the radial direction of the whole column.
2. The pCEC-SERS combined on-line analysis and detection method based on the monolithic column as recited in claim 1, wherein the formula of the silanization reagent polymerization solution comprises a three-way pore-forming agent consisting of silanization reagent, Cetyl Trimethyl Ammonium Bromide (CTAB), water and absolute ethyl alcohol.
3. The pCEC-SERS combined on-line analysis and detection method based on monolithic column of claim 2, wherein the formulation of the silanization reagent comprises Tetraethoxysilane (TEOS) and N- (beta-aminoethyl) -gamma-aminopropyltriethoxysilane (AEAPTES).
4. The pCEC-SERS online analysis and detection method based on the monolithic column as claimed in claim 3, wherein the mass percentage of the silanization reagent polymerization solution is 100%, and the mass percentage of each component is as follows: 41.08% of tetraethoxysilane, 10.68% of N- (beta-aminoethyl) -gamma-aminopropyltriethoxysilane, 2.44% of hexadecyltrimethylammonium bromide, 11.01% of water and 34.79% of absolute ethyl alcohol.
5. The pCEC-SERS combined on-line analysis and detection method based on the monolithic column as claimed in claim 2, wherein the modified nano-gold on the monolithic column is obtained by uniformly distributing nano-gold particles on the surface of a monolithic column polymerization column bed through stronger adsorption between amino and gold; the gold nanoparticles are prepared by a sodium citrate reduction method, the surfaces of the gold nanoparticles have negative charges, and the particle size of the gold nanoparticles is 50nm to 60 nm.
6. The pCEC-SERS combined on-line analysis and detection method based on the monolithic column as claimed in claim 1, wherein the capillary is a quartz capillary with far ultraviolet optics, ultraviolet optics or infrared optics, and the inner diameter of the quartz capillary is 100 μm.
7. The method for pCEC-SERS combined on-line analysis and detection based on monolithic column as claimed in claim 2, wherein the water in the silanization reagent polymerization solution component is ultrapure water, the resistivity is 18.25 MOmega, and the water is filtered by a filter membrane with the pore diameter of 0.22 μ M.
8. The pCEC-SERS combination on-line analysis and detection method based on the monolithic column as claimed in claim 1, wherein the SERS detection window of the monolithic column is perpendicular to the excitation light direction of the Raman spectrometer, and the SERS signal of the trace analyte is obtained by adjusting the focal length at the position with SERS effect in the monolithic capillary column.
9. The pCEC-SERS combined on-line analysis and detection method based on the monolithic column as recited in claim 1, wherein the two sections of silica gel hybrid monolithic columns with different charges form electroosmotic flows in different directions on two sides of the interface respectively, fluid pressure-reverse electroosmotic flow constant speed accumulation and chromatographic enrichment of functional substrates are applied on the front section of the interface to realize rapid enrichment and separation of samples, fluid pressure-forward electroosmotic flow is applied on the rear section (detection end) to drive carrier liquid to elute and analyze substances to be detected, and SERS high-sensitivity detection is performed on the monolithic column.
10. The integrated-column-based pCEC-SERS combined online analysis and detection method according to any one of claims 1 to 9, characterized in that: the detection steps are as follows:
s1: preparing a polyamino silica gel hybrid monolithic column:
weighing the ternary pore-forming agent CTAB, water and absolute ethyl alcohol in proportion into a 5mL glass bottle, carrying out vortex oscillation to form a uniform solution, placing the uniform solution in an ice bath ultrasonic treatment at 0 ℃ for 5min, weighing the monomers TEOS and AEAPTES in proportion according to claim 4 into the glass bottle containing the ternary pore-forming agent solution, and carrying out ice bath ultrasonic treatment at 0 ℃ for 30s to form a uniform pre-polymerization solution. Injecting the pre-polymer solution into a pretreated quartz capillary,sealing two ends with rubber pads, placing in 40 deg.C water bath for constant temperature reaction for 24h, taking out capillary column, cutting off a small part of two ends, placing in 120 deg.C oven, heating for 3h, and removing ethanol, unreacted silica gel monomer and dried colloid. Washing the monolithic column with high pressure solvent pump after drying to remove unreacted residue to obtain NH with surface rich in positive charge ions3 +The polyamino silica gel hybrid monolithic column;
s2: preparing nano gold particles:
heating 200mL of tetrachloroauric acid aqueous solution with the mass fraction of 0.01% to boiling, quickly adding 1.4mL of sodium citrate aqueous solution with the mass fraction of 1%, changing the color of the solution from light yellow to black after about 1min, changing the solution into brownish red after 2-3 min, continuously keeping slight boiling for 40min, stopping reaction, cooling in water bath, and preparing gold particle colloidal solution with the particle size of about 55 nm;
s3: preparing two sections of block monolithic column polymeric materials with different charges respectively:
introducing the nano-gold colloidal solution obtained in the step S2 into a polyamino silica gel hybrid monolithic column through a high-pressure infusion pump, and modifying negatively charged nano-gold particles at one end of the monolithic column so as to uniformly distribute the negatively charged nano-gold particles at one end of the monolithic column to form two sections of monolithic column materials with different charges respectively;
s4: the pCEC-SERS combined on-line analysis and detection method based on the monolithic column comprises the following steps:
one end of an amino section of two segmented integral columns with different charges is connected with a capillary electrochromatography for enrichment and separation of an object to be detected, the integral column modifies a nanogold section to be used as an SERS active substrate, and laser of a Raman spectrometer is focused on the integral column and is perpendicular to the radial direction of the integral column for detection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011307808.6A CN112666272A (en) | 2020-11-20 | 2020-11-20 | pCEC-SERS combined on-line analysis and detection method based on monolithic column |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011307808.6A CN112666272A (en) | 2020-11-20 | 2020-11-20 | pCEC-SERS combined on-line analysis and detection method based on monolithic column |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112666272A true CN112666272A (en) | 2021-04-16 |
Family
ID=75403482
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011307808.6A Pending CN112666272A (en) | 2020-11-20 | 2020-11-20 | pCEC-SERS combined on-line analysis and detection method based on monolithic column |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112666272A (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7655477B1 (en) * | 2003-02-26 | 2010-02-02 | Science Applications International Corporation | System and method for the separation of analytes |
| CN103994991A (en) * | 2014-05-21 | 2014-08-20 | 华东理工大学 | Preparation method of surface-enhanced raman spectrum (SERS) substrate based on capillary monolithic column |
| US20140373649A1 (en) * | 2013-03-13 | 2014-12-25 | Baker Hughes Incorporated | Use of detection techniques for contaminant and corrosion control in industrial processes |
| CN110793955A (en) * | 2019-11-07 | 2020-02-14 | 江苏师范大学 | Rapid separation-qualitative method for chemical reaction product |
-
2020
- 2020-11-20 CN CN202011307808.6A patent/CN112666272A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7655477B1 (en) * | 2003-02-26 | 2010-02-02 | Science Applications International Corporation | System and method for the separation of analytes |
| US20140373649A1 (en) * | 2013-03-13 | 2014-12-25 | Baker Hughes Incorporated | Use of detection techniques for contaminant and corrosion control in industrial processes |
| CN103994991A (en) * | 2014-05-21 | 2014-08-20 | 华东理工大学 | Preparation method of surface-enhanced raman spectrum (SERS) substrate based on capillary monolithic column |
| CN110793955A (en) * | 2019-11-07 | 2020-02-14 | 江苏师范大学 | Rapid separation-qualitative method for chemical reaction product |
Non-Patent Citations (1)
| Title |
|---|
| 刘婵等: "金纳米粒子修饰的氨基硅胶整体柱的制备及超灵敏表面增强拉曼散射检测", 《高等学校化学学报》 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Schweitz et al. | Molecularly imprinted microparticles for capillary electrochromatographic enantiomer separation of propranolol | |
| US8597508B2 (en) | Sol-gel monolithic column with optical window and method of making | |
| Hayes et al. | Sol− Gel Open Tubular ODS Columns with Reversed Electroosmotic Flow for Capillary Electrochromatography | |
| Sýkora et al. | Application of gold nanoparticles in separation sciences | |
| Chen et al. | Chemically l-phenylalaninamide-modified monolithic silica column prepared by a sol− gel process for enantioseparation of dansyl amino acids by ligand exchange-capillary electrochromatography | |
| Zhang et al. | Novel polymer monolith microextraction using a poly (methacrylic acid-ethylene glycol dimethacrylate) monolith and its application to simultaneous analysis of several angiotensin II receptor antagonists in human urine by capillary zone electrophoresis | |
| JP4920674B2 (en) | Structure, separation element, separation device, capture element, detection device, method for producing the same, and method for separating and detecting target substance | |
| Cheong et al. | Comprehensive overview of recent preparation and application trends of various open tubular capillary columns in separation science | |
| US8012763B2 (en) | Analysis method effected with rapid analyte chemical separation and quick detection | |
| US6998040B2 (en) | Sol-gel open tubular ODS columns with charged inner surface for capillary electrochromatography | |
| US20070170056A1 (en) | Microscale electrochemical cell and methods incorporating the cell | |
| CN110646405A (en) | High-flux detection device for Raman spectrum rapid analysis and detection method thereof | |
| Kist et al. | Separation of biomolecules using electrophoresis and nanostructures | |
| CN112666272A (en) | pCEC-SERS combined on-line analysis and detection method based on monolithic column | |
| US8932524B2 (en) | Apparatus for effecting analysis with rapid analyte chemical separation and subsequent detection | |
| Kitagawa et al. | One-step immobilization of cationic polymer onto a poly (methyl methacrylate) microchip for high-performance electrophoretic analysis of proteins | |
| Fan et al. | Surface modification with BSA blocking based on in situ synthesized gold nanoparticles in poly (dimethylsiloxane) microchip | |
| Xue et al. | A microscale solid-phase extraction poly (dimethylsiloxane) chip for enrichment and fluorescent detection of metal ions | |
| CN109908874B (en) | Novel MoS2QDs @ MIPs molecularly imprinted polymer and preparation method thereof | |
| Wei et al. | In‐situ preparation of porous monolithic polymer inside hollow fiber as a micro‐solid phase extraction device for glucocorticoids in cosmetics | |
| Wang et al. | Preparation of the capillary-based microchips for solid phase extraction by using the monolithic frits prepared by UV-initiated polymerization | |
| Chen et al. | Combination of flow injection with electrophoresis using capillaries and chips | |
| CN111122544A (en) | Preparation method of enrichment type surface enhanced Raman scattering substrate based on capillary action | |
| Chen et al. | Fabrication of a fiberglass-packed channel in a microchip for flow injection analysis | |
| US20040191920A1 (en) | Simultaneous chemical separation and plural-point surface-enhanced raman spectral detection |
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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210416 |
|
| RJ01 | Rejection of invention patent application after publication |