CN113376229A - Tetracycline doped polyaniline electrode, preparation method and application thereof - Google Patents
Tetracycline doped polyaniline electrode, preparation method and application thereof Download PDFInfo
- Publication number
- CN113376229A CN113376229A CN202110516684.0A CN202110516684A CN113376229A CN 113376229 A CN113376229 A CN 113376229A CN 202110516684 A CN202110516684 A CN 202110516684A CN 113376229 A CN113376229 A CN 113376229A
- Authority
- CN
- China
- Prior art keywords
- electrode
- tetracycline
- doped polyaniline
- tobacco
- tube
- 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
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/28—Electrolytic cell components
- G01N27/30—Electrodes, e.g. test electrodes; Half-cells
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D7/00—Electroplating characterised by the article coated
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D9/00—Electrolytic coating other than with metals
- C25D9/02—Electrolytic coating other than with metals with organic materials
Landscapes
- Chemical & Material Sciences (AREA)
- Electrochemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Molecular Biology (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Macromolecular Compounds Obtained By Forming Nitrogen-Containing Linkages In General (AREA)
Abstract
The invention belongs to the technical field of tobacco chemistry. The invention discloses a tetracycline-doped polyaniline electrode, wherein tetracycline-doped polyaniline is deposited on the surface of a substrate electrode. The invention also discloses a preparation method of the tetracycline doped polyaniline electrode and application of the tetracycline doped polyaniline electrode in detection of total anions in tobacco. The tetracycline doped polyaniline electrode is an all-solid-state electrode, is convenient to prepare, high in response speed, good in stability and reproducibility and small in internal resistance, can be used for potential detection of total anions of tobacco, and has the advantages of wide response range, short response time, good detection reproducibility, strong pollution resistance and the like.
Description
Technical Field
The invention belongs to the technical field of tobacco chemistry, and particularly relates to an electrode, a preparation method thereof and application of the electrode in detection of total anions of tobacco.
Background
Polyaniline is one kind of conducting polymer material, has special electrical and optical properties, and may be doped to have conductivity and electrochemical performance. After being processed by certain steps, the polyaniline can be used for preparing various devices and materials with special functions, such as biological or chemical sensors, electron field emission sources, reversible lithium battery electrode materials, antistatic and electromagnetic shielding materials, conductive fibers, anticorrosion materials and the like. Polyaniline has been widely researched and applied due to its easily available raw materials, simple synthesis process, good chemical and environmental stability, and the like[1-5]. The structure of the polyaniline-doped product is mainly explained by a polaron lattice model and a tetracyclic benzoquinone variant model. The main doping point of polyaniline is the imine nitrogen atom. The positive charges carried by the protons are transferred by the charges inside the molecular chain, and are periodically distributed along the molecular chain. And phenylenediamine and quinonediimine must be present together to ensure effective protonic acid doping. Proton doping is the key to the transition of polyaniline from the insulating state to the metallic state. The polyaniline in an intrinsic state is an insulator, and the polyaniline can be electrically oxidized by protonic acid doping or electrooxidationConductivity is improved by dozens of orders of magnitude[5]。
The inorganic and organic anions in tobacco are closely related to the quality, for example, the content of chlorine in tobacco leaves is closely related to the quality[7-9]. When the chlorine content is high, the chlorine can play a role in flame retardance on the combustion of tobacco leaves and can also deteriorate the color quality of the tobacco leaves in humid atmosphere. Thus. The chlorine content is an important quality index in the chemical identification of tobacco leaves and products thereof. Organic acids have important effects on both tobacco quality and smoke, especially volatile organic acids, which, although present in very low amounts (up to 0.1-0.2%, and in some cases even only 0.01-0.05%), have far more effects on the sensory quality of tobacco than polybasic and higher fatty acids. Non-volatile organic acids such as malic acid and citric acid can regulate pH value of tobacco and smoke, and make taste mellow[10]. The content of organic acid is an important factor influencing the quality of tobacco and is listed as an effective index for evaluating the quality of tobacco[7-10]. Therefore, the research on the influence of the organic acid on the quality of the tobacco leaves and the distribution difference of the organic acid in the tobacco leaves has important significance on the production of high-quality tobacco leaves.
Polyaniline has been widely regarded as having high electrical conductivity, simple synthesis method, convenient doping, stability to water and oxygen, high charge storage capacity and good electrochemical performance in the aspects of electrocatalysis, secondary power supply and the like[1-5]. Many studies have been made on the synthesis, electrochemical characteristics, and electropolymerization mechanism. In recent years, conductive polymer thin film modified electrodes have been the focus of research as potentiometric sensors, but are mainly used as pH sensors.
In the patent, the applicant firstly explores that the tetracycline hydrochloride is doped with polyaniline by an electrochemical method to prepare the tobacco organic acid potential sensor, and after deep research, the electrode is actually a broad-spectrum anion potential sensor, and the logarithmic concentration value and the potential of nearly thirty inorganic and organic anions have a certain linear relationship in a certain concentration range. In the patent, a substrate electrode is placed in an acid solution containing tetracycline and aniline, and is subjected to constant potential oxidation or cyclic voltammetry scanning within a certain potential range, so that a broad-spectrum anionic potential sensor finished product can be obtained. It has certain linear relation to the logarithm value of the potential concentration of nearly thirty inorganic and organic anions. The all-solid-state electrode has the advantages of convenient preparation, high response speed, good stability and reproducibility, small internal resistance and obvious potential detection effect when being used for tobacco total anions.
Reference to the literature
[1]Wang Hsing-Lin,Romero Robert J,Mattes Benjamin R,Effect ofprocessing conditions on the properties of high molecular weight conduc-tivepolyaniline fiber,Journal of Polymer Science,2000,38,194-195,203.
[2]Arun Kumar,ManikaKhanuja,Template-free graphitic carbon nitride nanosheets coated with polyanilinenanofibers as an electrode material for supercapacitor applications,Renewable Energy,2021,171,1246-1256.
[3]Abdul-Rahman F.Al-Betar,Enhanced electrocatalytic water oxidation using cobalt-based polyanilinehybrid assembly,Synthetic Metals,2021,275,116738.
[4]Haohan Chen,Youhe Xiang,RongfengCai,Liang Zhang,Yuting Zhang,Nandi Zhou,An ultrasensitive biosensor for dual-specific DNA based on deposition of polyaniline on a self-assembled multi-functional DNA hexahedral-nanostructure,Biosensors and Bioelectronics,2021,179,113066.
[5] Yi Sixing, Lu Wen Tao, Li Xiaoquan, Guo Cuo, research progress of polyaniline thermoelectric composite material, macromolecule Notification, 2020, (12),58-62.
[6] Wanruixin, uses chloride ion method to greatly determine the chlorine in tobacco leaf, Chinese tobacco science and technology, 1981, (4),27-28.
[7] Yijiang, Turmei, Zhang Wei, Zhouxiang, Yi Zhen Xian, fan Feng, Wang Ke, Zhouqian, the influence of organic acids on the quality of tobacco leaves and the distribution difference in tobacco leaves, 2013,27,695 + 699.
[8] The research of measuring anions in tobacco by using a homogenization method extraction-ion chromatography is disclosed in the university of Yunnan province, 2009,18, 325-one 327.
[9] Local standards of Guizhou province, a gas chromatography for measuring non-volatile organic acids of tobacco and tobacco products, a quality and technology supervision bureau 7 of Guizhou province, a standard number: DB 52/T1309- & lt 2018 & gt, published in 2018 on 08-month and 13-month days in 2019 and implemented on 2019 on 2-month and 13-month.
[10] Rongqiong, xuedan, yangjun, jinlan feng, jinpalaming, difference in the content of mainly non-volatile organic acids in different cigarettes and tobacco leaves, tobacco science, 2009, (18),33-37+64.
Disclosure of Invention
The invention aims to provide an electrode for detecting total anions of tobacco, which has the advantages of wide response range, good detection performance and long service life, and a preparation method thereof.
The technical scheme of the invention is as follows:
the invention discloses a tetracycline-doped polyaniline electrode, wherein tetracycline-doped polyaniline is deposited on the surface of a substrate electrode.
Preferably, the tetracycline-doped polyaniline deposited on the surface of the base electrode is a linear aggregate with branches and has a porous loose structure.
Preferably, the tetracycline-doped polyaniline deposited on the surface of the substrate electrode is obtained by potentiostatic electrolytic oxidation deposition or continuous cyclic voltammetry deposition.
Preferably, the electrode body of the substrate electrode is one of a platinum wire, a gold wire or a carbon rod.
The invention discloses a preparation method of the tetracycline-doped polyaniline electrode in a second aspect, which is characterized by comprising the following steps:
closely winding an electrode lead 1 around the periphery of an electrode body 2 for 4-15 circles, and welding to fix the electrode lead 1 and the electrode body 2 together;
putting the electrode body 2 with the electrode lead 1 into the electrode tube 4, wherein one part of the electrode lead 1 is outside the electrode tube 4;
thirdly, sealing and fixing the electrode body 2 in the electrode tube 4 by using an epoxy resin prepolymer 5 containing a curing agent;
fourthly, the end with the electrode body is polished into a round shape, and then the matrix electrode 6 is obtained;
fifthly, placing the substrate electrode 6 obtained in the step (iv) in an acid solution 12 containing tetracycline and aniline, and carrying out constant potential oxidation for 1 to 5min under the condition of 0.7V to 0.9V (relative saturated calomel electrode), or scanning for 5 to 50 circles at a sweep rate of 10mV/s to 500mV/s within the range of-0.2V to 1.5V (relative saturated calomel electrode); thus obtaining the electrode 7 with tetracycline doped polyaniline deposited on the surface.
Preferably, the electrode lead 1 in the step I is a copper wire or an aluminum wire, and the diameter is 0.1mm-0.5 mm; the electrode body 2 is one of platinum wire, gold wire or carbon rod, the diameter is 0.1mm-6mm, and the length is 5mm-20 mm; the welding uses molten soldering tin 3; and step two, the electrode tube 4 is a plastic tube or a glass tube, the inner diameter of the electrode tube is 0.5mm-8mm, and the length of the electrode tube is 30mm-120 mm. The electrode tube 4 is made of an insulating material.
Preferably, the epoxy resin prepolymer 5 containing the curing agent in the third step is cured at room temperature for more than 20 hours, or at 60 ℃ for more than 3 hours.
Preferably, the model of the metallographic abrasive paper obtained in the step (iv) is W5, and the mesh number of the metallographic abrasive paper is 1200 meshes; other types of sandpaper may also be selected as desired.
Preferably, the preparation method of the acidic solution 12 containing tetracycline and aniline comprises the following steps: adding a certain amount of aniline and tetracycline hydrochloride into an acid solution with the concentration of 0.2-5mol/L, leading the concentration of aniline to be 50-500mmol/L and the concentration of tetracycline hydrochloride to be 1-100mmol/L, and then introducing nitrogen to remove oxygen, thus obtaining the acid solution containing tetracycline and aniline; the acid used is one of hydrochloric acid, concentrated sulfuric acid or phosphoric acid.
The third aspect of the invention discloses the application of the tetracycline-doped polyaniline electrode 7 in the detection of tobacco total anions.
The invention has the beneficial effects that:
1. the electrode is prepared by depositing tetracycline doped polyaniline on the surface of a matrix electrode by a potentiostatic oxidation method or a continuous cyclic voltammetry method for the first time. The electrode has the advantages of wide response range, short response time, good detection reproducibility, strong pollution resistance and the like when being used for detecting the total anions of the tobacco.
2. The tetracycline doped polyaniline electrode is in an all-solid state, and can be directly polished and updated, so that the reusability, mechanical strength, stability and service life of the electrode are greatly improved.
3. The tetracycline doped polyaniline electrode has the advantages of simple and convenient manufacturing process, low cost of raw materials and batch processing.
4. The tetracycline doped polyaniline electrode can be used for potential electrochemical detection of microfluidic chip electrophoresis, flow injection analysis, liquid chromatography and the like, and has wide application prospects in the fields of tobacco chemistry, food and drug analysis, environmental monitoring, clinical diagnosis and the like.
Drawings
FIG. 1 is a flow chart of the preparation of a tetracycline-doped polyaniline electrode of the present invention; the steps are from (A) to (G).
Fig. 2 is a surface scanning electron microscope photograph of the tetracycline-doped polyaniline electrode prepared by the potentiostatic oxidation method in example 1 of the present invention, with a magnification of 10000.
FIG. 3 shows different concentrations of KI, NaBr, KCl, NaAc and K in the electrode pair prepared in example 12SO4Potential response curve of (2).
FIG. 4 is a continuous cyclic voltammogram of example 2, in which tetracycline doped polyaniline is deposited on the surface of the base electrode using platinum as the electrode body; the scanning range is as follows: -0.2V to +1.5V, scan rate of 100mV/s, for 24 scans.
The reference signs are: 1. an electrode lead; 2. an electrode body; 3. melting soldering tin; 4. an electrode tube; 5. epoxy resin prepolymer containing curing agent; 6. a base electrode; 7. a tetracycline-doped polyaniline electrode; 8. a pair of electrodes; 9. a saturated calomel electrode; 10. an electrolytic cell plug; 11. an electrolytic cell; 12. an acidic solution containing tetracycline and aniline.
Detailed Description
The invention is further described below by way of examples and figures:
example 1: a tetracycline-doped polyaniline electrode is prepared by potentiostatic oxidation, and the preparation steps are shown in figure 1.
Cutting a carbon rod with the diameter of 1.5mm into small sections with the length of 20mm to be used as an electrode body 2; taking a copper wire with the diameter of 0.2 mm as an electrode lead 1, winding one end of the copper wire into a spiral tube with eight circles, inserting the electrode body 2 into the spiral tube, dropwise adding molten soldering tin 3 at the spiral tube by using an electric iron for welding, and tightly locking the electrode body 2 by the welded copper wire spiral tube due to expansion caused by heat and contraction caused by cold; as shown in (A), (B) and (C) of FIG. 1;
penetrating the electrode body 2 connected with the electrode lead 1 into a plastic electrode tube 4 with the inner diameter of 2mm, and enabling the electrode body 2 to extend out of the electrode tube 4 by about 2mm, wherein one part of the electrode lead 1 is outside the electrode tube 4; as shown in fig. 1 (D);
dropping epoxy resin 5 containing a curing agent into a gap between the electrode tube 4 and the electrode body 2 until the electrode body 2 in the tube is completely embedded, and then curing at room temperature for more than 20 hours or at 60 ℃ for more than 3 hours, as shown in fig. 1 (E);
polishing one end of the electrode body 2 with 1200 mesh metallurgical sand into a round shape to obtain a matrix electrode 6 as shown in (F) of FIG. 1; in order to reduce the eccentricity of the electrode body 2, the outer diameter of the electrode body 2 is only slightly smaller than the inner diameter of the electrode tube 4, and the concentricity of the electrode body 2 in the electrode tube 4 can also be improved by the spiral tube connector at the joint of the electrode lead 1 and the electrode body 2;
diluting concentrated sulfuric acid with distilled water to prepare a solution with the concentration of 1mol/L, then weighing a certain amount of aniline and tetracycline hydrochloride, adding the aniline and tetracycline hydrochloride into the sulfuric acid solution, performing ultrasonic-assisted dissolution to ensure that the final concentrations of aniline and tetracycline hydrochloride are 100mmol/L and 50mmol/L respectively, and introducing pure nitrogen to remove oxygen in the aniline and tetracycline hydrochloride to obtain an acid solution 12 containing tetracycline and aniline; placing an acidic solution 12 containing tetracycline and aniline in an electrolytic cell 11; cleaning the matrix electrode 6, placing the cleaned matrix electrode in an electrolytic cell 11, and carrying out constant potential oxidation for 3min at a potential of +0.85V to obtain a tetracycline-doped polyaniline electrode 7; the reference electrode is a saturated calomel electrode 9; the electrolytic cell 11 shown in (G) of FIG. 1 has a counter electrode 8 and a cell plug 10.
Fig. 2 is a scanning electron micrograph of the surface of the tetracycline-doped polyaniline electrode obtained in example 1, the magnification being 10000. As can be seen from fig. 2, the tetracycline-doped polyaniline is a linear aggregate with branches, and has a porous loose structure; therefore, the surface area is large, and the response sensitivity of the electrode can be improved.
The tetracycline-doped polyaniline electrode 7 obtained in example 1 was used to measure the linear range, slope, and detection lower limit of over thirty inorganic and organic anions; and the linearity range, the inclination and the detection lower limit of more than thirty kinds of inorganic and organic anions are measured by taking the electrode modified by polyaniline without doping tetracycline as a comparison electrode under the same condition; the comparison is shown in table 1. As can be seen from table 1, the linear range of the electrode obtained in example 1 is higher than that of the comparative electrode by about 2 orders of magnitude, and the electrode has a slope higher than that of the comparative electrode because it corresponds to only low-concentration anions, so that the detection sensitivity is higher, and the lower limit of detection is higher than that of the comparative electrode by about 2 orders of magnitude. FIG. 3 shows different concentrations of KI, NaBr, KCl, NaAc and K in the electrode pair obtained in example 12SO4Potential response curves for several typical electrolytes. As can be seen from FIG. 3, the electric potential of the tetracycline-doped polyaniline electrode and the negative logarithm of the concentration of several anions in the concentration range of 100mmol/L to 0.01mmol/L form a linear relationship, the lower detection limits of the tetracycline-doped polyaniline electrode to iodide ions, bromide ions, chloride ions, acetate ions and sulfate ions are respectively 5, 20 and 3 mu mol/L, and the detection requirements of anion detection of practical samples such as tobacco extract and the like can be met. Therefore, the electrode obtained in the embodiment 1 has a certain linear relation to the numerical value, and has the advantages of wide linear range, low detection lower limit, high response speed, high stability and reproducibility and small internal resistance. And the electrode obtained in the example 1 is an all-solid-state electrode, and the preparation is convenient.
TABLE 1 comparison of Linear Range, slope and lower detection limit of electrode and comparative electrode obtained in example 1 (reference electrode is saturated calomel electrode)
To investigate the feasibility of the electrode obtained in example 1 in detecting the total anions in tobacco extract, the total anions in tobacco extract were detected using the electrode obtained in example 1.
The preparation method of the tobacco extract comprises the following steps: taking a tobacco sample, drying the tobacco sample in a drying box at 60 ℃ for 3 hours, and crushing the tobacco sample to below 80 meshes by using a crusher; accurately weighing 1 g of powder sample, dispersing in 100ml of distilled water, performing ultrasonic extraction for 60min, centrifuging at the rotating speed of 4000rpm for 30min, and taking supernatant for measuring total anions of the tobacco extract. According to the reference[8]The inorganic anions in the tobacco mainly comprise chloride ions, fluoride ions, nitrate ions, nitrite ions, sulfate ions, nitrite ions and the like; wherein the concentration of chloride ion is highest, the typical content of the chloride ion in tobacco is 22-35mg/g (0.6-1.0mmol/g), the typical phosphate radical content is 8.6-12.8mg/g (0.08-0.13mmol/g), the typical sulfate radical content is 0.65-2.3mg/g (0.006-0.023mmol/g), the typical nitrate radical content is 0.8-2.2mg/g (0.01-0.05mmol/g)[8](ii) a The molar content (mmol/g) of chloride ions in tobacco is usually more than about 10 times of the concentration of other ions, and is the main contributing ion of the total anion potential; the organic acid in the tobacco is mainly volatile organic acid and non-volatile organic acid, wherein the content of the volatile organic acid is very low and can reach 0.1-0.2 percent at most, and the influence on the electrode potential is negligible due to the low relative content concentration; the tobacco has a non-volatile organic acid content of about 10-16%[9,10]Mainly comprises malic acid, oxalic acid and citric acid, the typical content of the malic acid in the tobacco is 40-90mg/g (0.3-0.7 mmol/g), the typical content of the oxalic acid is 8-18mg/g (0.08-0.19mmol/g) and the typical content of the citric acid is 6-12mg/g (0.03-0.06mmol/g), obviously, the content of the malic acid in the tobacco is usually a plurality of times or even more than 10 times of the content of other non-volatile organic acids, which is close to the molar content of tobacco chloride ions, because the tobacco extract is slightly acidic, the pH value is about 5, the malic acid, the oxalic acid and the citric acid mainly exist in the forms of malic acid hydrogen radical ions, oxalic acid hydrogen radical ions and citric acid dihydrogen radical ions under the acidity, and are monovalent ions as well as chloride ions, so that convenience is brought to total anion detection.
The method for detecting the total anions of the tobacco extract by using the electrode obtained in example 1 comprises the following steps: the electrode obtained in example 1 and a reference electrode saturated calomel electrode were inserted into 50 ml of 0.1mmol/L KCl aqueous solution, and the potential of the electrode relative to the saturated calomel electrode was measured to be +154.1mV by a potentiometer; adding 0.045 ml of 1mol/L KCl aqueous solution, neglecting the volume of the added standard solution, wherein the concentration of chloride ions in the solution is 1mmol/L, the measured potential is +95.8mV, and the Nernst slope is 154.1-95.8 ═ 58.3 mV; adding 0.05mL of 1mol/L KCl aqueous solution into 50 mL of tobacco extract, adding the tobacco solution with the standard KCl concentration of 1mmol/L into the 1mmol/L KCl aqueous solution, measuring the potential of the solution to be reduced to +35.1 mV, measuring the mixed sample solution according to the working curve of the KCl aqueous solution, deducting the standard background concentration of 1mmol/L KCl, and considering the double dilution to obtain the total anion concentration in the tobacco extract of 8.85 multiplied by 2 to 16.7 mmol/L; since the sample solution was 1 gram of tobacco powder extracted with 100mL of distilled water, the total anion molar content in this tobacco sample was determined to be 1.67mmol/g, the content determined in triplicate was 1.67, 1.72 and 1.61mmol/g, the average was 1.67mmol/g and the relative standard deviation RSD was 2.7%. The method for measuring the total anions in the tobacco extract by using the electrode obtained in the embodiment 1 is higher in precision and strong in anti-pollution capacity of the electrode.
Example 2: the tetracycline-doped polyaniline electrode is prepared by using a continuous cyclic voltammetry method. Preparation procedure example 1 is also shown in FIG. 1. The difference from the embodiment 1 is that: scanning for 24 circles in an acid solution containing tetracycline and aniline at a sweep rate of 10-500 mV within the range of-0.2V to +1.5V to obtain a tetracycline-doped polyaniline electrode; see figure 4. The scanning electron microscope conditions of the surface of the tetracycline-doped polyaniline electrode obtained in example 2 were the same as those of example 1.
The tetracycline-doped polyaniline electrode obtained in example 2 was used to measure the linear range, slope, and detection lower limit of thirty or more inorganic and organic anions, which were the same as those in example 1; measuring the linear range, the slope and the lower detection limit of more than thirty inorganic and organic anions by using a tetracycline-free polyaniline modified electrode as a comparison electrode; the comparison is shown in table 2. As can be seen from table 2, the comparison results are similar to those of example 1. Therefore, the electrode obtained in example 2 has a certain linear relationship to the numerical value, the linear range is wide, the lower detection limit is low, the response speed is high, the stability and reproducibility are good, the internal resistance is small, and the electrode obtained in example 2 is an all-solid-state electrode and is convenient to prepare.
The tobacco extract liquid of example 1 was tested in the same manner using the electrode prepared in example 2, and the result was that the average molar content of total anions was 1.70mmol/g and the relative standard deviation RSD was 3.3%. Similar to example 1.
TABLE 2 comparison of Linear Range, slope and lower detection limit of electrode and reference electrode obtained in example 2 (reference electrode is saturated calomel electrode)
Comparing the data in the table 1 and the table 2, it can be found that the tetracycline-doped polyaniline electrode prepared by the potentiostatic method and the cyclic voltammetry has little difference in linear range, slope and detection lower limit, and can be used for determining total anions in the tobacco extract.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (10)
1. A tetracycline-doped polyaniline electrode is characterized in that tetracycline-doped polyaniline is deposited on the surface of a substrate electrode.
2. The tetracycline-doped polyaniline electrode according to claim 1, wherein the tetracycline-doped polyaniline deposited on the surface of the base electrode is a linear aggregate with branches and has a porous loose structure.
3. The tetracycline-doped polyaniline electrode of claim 1, wherein the tetracycline-doped polyaniline deposited on the surface of the base electrode is deposited by potentiostatic electrolytic oxidation deposition or continuous cyclic voltammetry.
4. The tetracycline-doped polyaniline electrode of claim 1, wherein the electrode body of the base electrode is one of a platinum wire, a gold wire, or a carbon rod.
5. A method for preparing the tetracycline-doped polyaniline electrode according to any one of claims 1-4, which comprises the following steps:
tightly winding an electrode lead (1) around the periphery of an electrode body (2) for 4-15 circles, and welding to fix the electrode lead (1) and the electrode body (2) together;
putting the electrode body (2) with the electrode lead (1) in the step I into an electrode tube (4), wherein one part of the electrode lead (1) is arranged outside the electrode tube (4);
thirdly, the electrode body (2) is hermetically fixed in the electrode tube (4) by using an epoxy resin prepolymer (5) containing a curing agent;
fourthly, the end with the electrode body is polished into a round shape, and then the basal body electrode (6) is obtained;
fifthly, placing the matrix electrode (6) obtained in the step (iv) in an acid solution containing tetracycline and aniline, and carrying out constant potential oxidation for 1-5 min at 0.7-0.9V; or scanning for 5 to 50 cycles at a sweep rate of 10mV/s to 500mV/s in the range of-0.2V to 1.5V; thus obtaining the electrode (7) with the tetracycline doped polyaniline deposited on the surface.
6. The preparation method according to claim 5, wherein the electrode lead (1) of step (i) is a copper wire or an aluminum wire with a diameter of 0.1mm to 0.5 mm; the electrode body (2) is one of platinum wire, gold wire or carbon rod, the diameter is 0.1mm-6mm, and the length is 5mm-20 mm; the welding uses molten solder (3); and step two, the electrode tube (4) is a plastic tube or a glass tube, the inner diameter of the electrode tube is 0.5mm-8mm, and the length of the electrode tube is 30mm-120 mm.
7. The method according to claim 5, wherein the epoxy resin prepolymer (5) containing a curing agent in step (iii) is cured at room temperature for 20 hours or more, or at 60 ℃ for 3 hours or more.
8. The preparation method according to claim 5, wherein the grinding of step (iv) is performed using 1200-mesh metallographic abrasive paper.
9. The method according to claim 5, wherein the acidic solution containing tetracycline and aniline is prepared by: adding a certain amount of aniline and tetracycline hydrochloride into an acid solution with the concentration of 0.2-5mol/L, leading the concentration of aniline to be 50-500mmol/L and the concentration of tetracycline hydrochloride to be 1-100mmol/L, and then introducing nitrogen to remove oxygen, thus obtaining the acid solution containing tetracycline and aniline; the acid used is one of hydrochloric acid, concentrated sulfuric acid or phosphoric acid.
10. Use of the tetracycline-doped polyaniline electrode (7) according to any one of claims 1-4 for tobacco total anion detection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110516684.0A CN113376229A (en) | 2021-05-12 | 2021-05-12 | Tetracycline doped polyaniline electrode, preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110516684.0A CN113376229A (en) | 2021-05-12 | 2021-05-12 | Tetracycline doped polyaniline electrode, preparation method and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113376229A true CN113376229A (en) | 2021-09-10 |
Family
ID=77572522
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110516684.0A Pending CN113376229A (en) | 2021-05-12 | 2021-05-12 | Tetracycline doped polyaniline electrode, preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113376229A (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU2013209296A1 (en) * | 2006-12-19 | 2013-08-08 | Apotex Technologies Inc | Pharmaceutically acceptable salts of thymodepressin and processes for their manufacture |
| WO2014021333A1 (en) * | 2012-07-31 | 2014-02-06 | 日本ケミコン株式会社 | Solid electrolytic capacitor and method for manufacturing same |
-
2021
- 2021-05-12 CN CN202110516684.0A patent/CN113376229A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU2013209296A1 (en) * | 2006-12-19 | 2013-08-08 | Apotex Technologies Inc | Pharmaceutically acceptable salts of thymodepressin and processes for their manufacture |
| WO2014021333A1 (en) * | 2012-07-31 | 2014-02-06 | 日本ケミコン株式会社 | Solid electrolytic capacitor and method for manufacturing same |
Non-Patent Citations (1)
| Title |
|---|
| 陈刚, 胡统理, 陆嘉星, 叶建农, 张剑霞, 李鹏程, 江世益: "聚苯胺掺杂土霉素修饰铂电极的电位响应", 华东师范大学学报(自然科学版), no. 01, pages 72 - 77 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Zhao et al. | Selective adsorption toward toxic metal ions results in selective response: electrochemical studies on a polypyrrole/reduced graphene oxide nanocomposite | |
| Salih et al. | Conducting polymer/ionic liquid composite modified carbon paste electrode for the determination of carbaryl in real samples | |
| Lindfors et al. | Raman and UV–vis spectroscopic study of polyaniline membranes containing a bulky cationic additive | |
| Mališić et al. | Exploration of MnO2/carbon composites and their application to simultaneous electroanalytical determination of Pb (II) and Cd (II) | |
| Li et al. | 3D electrochemical sensor based on poly (hydroquinone)/gold nanoparticles/nickel foam for dopamine sensitive detection | |
| Khan et al. | Preparation and properties of novel sol-gel-derived quaternized poly (n-methyl pyrrole)/Sn (II) SiO 3/CNT composites | |
| Chen et al. | A Non‐Enzymatic Hydrogen Peroxide Sensor Based on Gold Nanoparticles/Carbon Nanotube/Self‐Doped Polyaniline Hollow Spheres | |
| Nie et al. | Simultaneous determination of folic acid and uric acid under coexistence of L-ascorbic acid using a modified electrode based on poly (3, 4-ethylenedioxythiophene) and functionalized single-walled carbon nanotubes composite | |
| Salandari-Jolge et al. | A novel three-dimensional network of CuCr 2 O 4/CuO nanofibers for voltammetric determination of anticancer drug methotrexate | |
| Hamidi et al. | Fabrication of bulk-modified carbon paste electrode containing α-PW12O403− polyanion supported on modified silica gel: Preparation, electrochemistry and electrocatalysis | |
| Sun et al. | A novel sensing platform based on a core–shell Fe@ Fe 3 C–C nanocomposite for ultrasensitive determination of vanillin | |
| Teker et al. | An enzyme‐free H2O2 sensor based on poly (2‐aminophenylbenzimidazole)/gold nanoparticles coated pencil graphite electrode | |
| Paczosa-Bator et al. | Application of graphene supporting platinum nanoparticles layer in electrochemical sensors with potentiometric and voltammetric detection | |
| Shang et al. | Electrodeposition of PdAu alloy nanoparticles on ionic liquid functionalized graphene film for the voltammetric determination of oxalic acid | |
| Rabie et al. | A Novel Electrochemical Sensor Based on Modified Carbon Paste Electrode with ZnO Nanorods for the Voltammetric Determination of Indole‐3‐acetic Acid in Plant Seed Extracts | |
| Nie et al. | Facile synthesis of poly (3, 4-ethylenedioxythiophene)/graphene nanocomposite and its application for determination of nitrite | |
| Srinivas et al. | Co/Co‐N@ Nanoporous Carbon Derived from ZIF‐67: A Highly Sensitive and Selective Electrochemical Dopamine Sensor | |
| Zhang | Electrochemical synthesis of self-doped polyaniline and its use to the electrooxidation of ascorbic acid | |
| Alsafrani et al. | Preparation, characterization and super electrocatalytic sensing study of polyaniline@ yttrium phosphate (PANI@ Y (III) PO4) nanocomposite | |
| Fotouhi et al. | MWCNT Modified Glassy Carbon Electrode: Probing Furazolidone‐DNA Interactions and DNA Determination | |
| Peng et al. | Preparation and characterization of a multi-cylinder microelectrode coupled with a conventional glassy carbon electrode and its application to the detection of dopamine | |
| CN113376229A (en) | Tetracycline doped polyaniline electrode, preparation method and application thereof | |
| CN107117599B (en) | Preparation method of chloro-hybrid graphene | |
| Xia et al. | Chitosan‐Based Hydrothermal Nanocarbon: Core‐Shell Characteristics and Composite Electrodes | |
| Lu et al. | Cobalt (II) Schiff base/large mesoporous carbon composite film modified electrode as electrochemical biosensor for hydrogen peroxide and glucose |
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 |