CN108776133B - Nano gold test paper film and application thereof in chloride ion detection - Google Patents

Nano gold test paper film and application thereof in chloride ion detection Download PDF

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CN108776133B
CN108776133B CN201810591101.9A CN201810591101A CN108776133B CN 108776133 B CN108776133 B CN 108776133B CN 201810591101 A CN201810591101 A CN 201810591101A CN 108776133 B CN108776133 B CN 108776133B
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CN108776133A (en
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许东
俞淑芳
殷月芹
林亲录
彭湘莲
郭鑫
王素燕
张琳
肖华西
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Hunan Zhixiang future Biotechnology Co.,Ltd.
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Central South University of Forestry and Technology
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Abstract

The invention discloses a nano-gold test paper film. The nano-gold test paper film provided by the invention is formed by loading nano-gold particles on the surface of the PVDF film. Based on the nano-gold test paper film, the invention also discloses application of the nano-gold test paper film in chloride ion detection. The detection method of the chloride ions comprises the following steps: mixing a sample to be detected with a nitric acid solution; adding the nano-gold test paper film into the mixed solution obtained in the step S1, reacting for 5-75min, and qualitatively detecting chloride ions when the nano-gold test paper film fades; and analyzing the light intensity value of the reacted nano gold test paper film through Image J software to obtain an optical signal of the nano gold test paper film, so as to realize quantitative detection of the concentration of the chloride ions in the solution to be detected. The nanogold test paper film provided by the invention is applied to detecting chloride ions, and has the advantages of high detection sensitivity, high speed, simplicity in operation and the like.

Description

Nano gold test paper film and application thereof in chloride ion detection
Technical Field
The invention relates to the technical field of chloride ions, in particular to a nanogold test paper membrane and application thereof in chloride ion detection.
Background
Sodium chloride (NaCl) is an essential substance in human life activities. It plays an important role in the balance of water and osmotic pressure in vivo, the digestion function of intestines and stomach, acid-base balance in vivo and the like. The excessive intake of salt causes a series of diseases, the diseases such as hypertension, gastric cancer, asthma, osteoporosis and the like are most concerned at present, and the excessive intake of salt (sodium) is listed as an eighth factor influencing human health. The world health organization recommends that daily salt intake be 5g per person.
The main detection methods of sodium chloride at present are as follows: titration, ion chromatography, capillary electrophoresis, and the like. The titration method has the advantages that the measured result has higher accuracy and the operation is simple and convenient; the defects of no good sensitivity, poor reproducibility and large error; the ion chromatography is mainly suitable for measuring various ion contents in aqueous solution, has good precision and accuracy, simple and convenient operation and convenient sample pretreatment, avoids the invasion of toxic chemicals to human bodies, can improve the analysis efficiency, but is expensive and not suitable for the application of actual production; the capillary electrophoresis method has the characteristics of simplicity, convenience, rapidness, high accuracy, good stability and the like, and is widely applied to the determination of the content of the injection.
The world health organization proposes that the test device should be of moderate cost, sensitive, specific, user-friendly, quick, no additional equipment required, and end-user oriented results. According to research, the paper-based colorimetric method has the advantages of high sensitivity, rapidness, convenience, suitability for field detection, strong specific functionality, no need of additional equipment, moderate price, simplicity and convenience in operation, easiness in analyzing and obtaining results and the like. However, in the related art, a technology for detecting sodium chloride by adopting a paper-based colorimetric method is rarely reported.
In view of the above, the present invention provides a method for detecting chloride ions by using a nanogold test paper film, which solves the above technical problems.
Disclosure of Invention
The invention aims to overcome the technical defects and provide the nanogold test paper film for detecting chloride ions, which has the advantages of high detection sensitivity, high speed, simplicity in operation and the like.
In order to solve the technical problems, the technical scheme of the invention is as follows:
a nano-gold test paper film is characterized in that nano-gold particles are loaded on the surface of a PVDF film.
Further, the preparation method of the nanogold test paper film comprises the following steps:
step S1: preparing a nano gold solution, namely adding a chloroauric acid solution into a boiling PVP aqueous solution, adding a proper amount of trisodium citrate under a boiling condition, stopping heating when the solution is completely changed into deep wine red from light yellow to gray, and cooling the solution to room temperature to obtain the nano gold solution;
step S2: and (4) preparing the nano-gold test paper film, namely putting the PVDF film into the nano-gold solution prepared in the step S1 for ultrasonic treatment, taking out the PVDF film loaded with the nano-gold particles after the ultrasonic treatment is finished, and air-drying to obtain the nano-gold test paper film.
Further, in step S2, the ultrasonic temperature is 45-55 deg.C, and the ultrasonic action time is 80-140 min.
Further, in step S1, the PVP aqueous solution is prepared from 70mL of ultrapure water and 50mL of PVP solution with a concentration of 0.1 mM; the dosage of the chloroauric acid solution is 5mL, and the concentration of the chloroauric acid solution is 24.28 mM; the addition amount of trisodium citrate is 12.5mL, and the mass fraction of trisodium citrate is 1%.
Further, in step S1, the maximum absorption peak of the nanogold solution is 527 nm.
Based on the nano-gold test paper film, the invention also provides an application of the nano-gold test paper film in chloride ion detection.
A method for detecting chloride ions comprises the following steps:
step S1: mixing a sample to be detected with a nitric acid solution;
step S2: and (4) adding the nano-gold test paper film into the mixed solution obtained in the step S1, reacting for 5-75min, and qualitatively detecting chloride ions when the nano-gold test paper film fades.
Further, step S2 further includes: and analyzing the light intensity value of the reacted nano gold test paper film through Image J software to obtain an optical signal of the nano gold test paper film, so as to realize quantitative detection of the concentration of the chloride ions in the solution to be detected.
Further, in step S1, the concentration of the nitric acid solution is 3 to 9 mol/L.
Further, in step S2, the reaction time was 55 min.
Compared with the prior art, the nano gold test paper film and the application thereof in chloride ion detection have the beneficial effects that:
the method comprises the steps of firstly, uniformly attaching the gold nanoparticles to a PVDF membrane to obtain a red AuNPs-PVDF (AuNPs are short for gold nanoparticles, PVDF represents polyvinylidene fluoride) gold nanoparticle test paper membrane with uniform color; and the nano gold particles can be etched in the nitric acid solution based on the chloride ions, so that the detection method with good response to the chloride ions is constructed, the chloride ions are quickly detected, the detection sensitivity of the detection method is high, and the operation is simple.
Secondly, the nano-gold test paper film provided by the invention has better selectivity to chloride ions and HSO4 -、Br-、CH3COO-、Hg2+、Cu2+、F-、I-、Pb2+The plasma has good anti-interference capability and very strong detection specificity on the chloride ions.
And thirdly, according to the detection method of chloride ions, the lowest detection limit of sodium chloride can reach 0.01%.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a naked eye visualization graph of the degree of uniformity of AuNPs distribution on a PVDF membrane under different ultrasonic temperature conditions;
FIG. 2 is a graph showing the analysis of the light intensity values of the uniformity of AuNPs distribution on a PVDF membrane under different ultrasonic temperature conditions;
FIG. 3 is a naked eye visualization graph of the degree of uniformity of AuNPs distribution on a PVDF membrane under different ultrasonication time conditions;
FIG. 4 is a graph of the analysis of the light intensity values of the uniformity of AuNPs distribution on PVDF membrane under different ultrasonic action time conditions;
FIG. 5 is a color response diagram of different reaction systems to a nano-gold test paper film;
FIG. 6 is a naked eye visual diagram of color response of mixed solution of sodium chloride and nitric acid with different concentrations to a nano-gold test paper film;
FIG. 7 is a light intensity value analysis chart of the nanogold test paper film under the condition of reacting for 5min in a mixed solution reaction system of sodium chloride and nitric acid with different concentrations;
FIG. 8 is a light intensity value analysis diagram of the reaction of the nano-gold test paper film in the mixed solution reaction system of sodium chloride and nitric acid with different concentrations for 35 min;
FIG. 9 is a light intensity analysis chart of the nanogold test paper film reacting for 55min in the mixed solution reaction system of sodium chloride and nitric acid with different concentrations;
FIG. 10 is a light intensity analysis chart of the nanogold test paper film in the reaction system of the mixed solution of sodium chloride and nitric acid with different concentrations for 75 min;
fig. 11 is an naked eye view of the selectivity of the nano-gold test paper film to chloride ions.
Detailed Description
In order to make the technical solutions in the embodiments of the present invention better understood and make the above objects, features, and advantages of the present invention more comprehensible, specific embodiments of the present invention are described below with reference to the accompanying drawings.
The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual values, and between the individual values may be combined with each other to yield one or more new ranges of values, which ranges of values should be considered as specifically disclosed herein.
Firstly, the nano-gold test paper film and the preparation method thereof provided by the invention are explained.
A nano-gold test paper film is characterized in that nano-gold particles are loaded on the surface of a PVDF film. The preparation method comprises the following steps:
step S1: preparing a nano gold solution, namely adding a chloroauric acid solution into a boiling PVP aqueous solution, adding a proper amount of trisodium citrate under a boiling condition, stopping heating when the solution is completely changed into deep wine red from light yellow to gray, and cooling the solution to room temperature to obtain the nano gold solution;
specifically, a 250mL three-neck flask is placed in a magnetic heating stirrer and a fixed condensation reflux device, 70mL of ultrapure water and 50mL of PVP solution with the concentration of 0.1mM are added into the three-neck flask, the three-neck flask is heated to boiling at 140 ℃, after the three-neck flask is completely boiled, 5mL of chloroauric acid solution with the concentration of 24.28mM is rapidly added, after the three-neck flask is boiled again, 12.5mL of trisodium citrate (the mass fraction is 1%) is rapidly added, the solution is changed from light yellow to gray and finally into dark wine red, heating is stopped when the solution is completely changed into dark wine red, the three-neck flask is removed from the oil bath, the nanogold gold solution is continuously subjected to condensation reflux stirring to room temperature, 2mL of the solution is sucked into a cuvette after the solution is cooled, an ultraviolet visible spectrophotometer is used for scanning the solution, the maximum absorption peak of the nanogold gold solution is measured; pouring the residual solution into a glass bottle, and refrigerating at 4 ℃.
All the above glass instruments were soaked in aqua regia overnight, washed with ultrapure water and dried for use.
Step S2: and (4) preparing the nano-gold test paper film, namely putting the PVDF film into the nano-gold solution prepared in the step S1 for ultrasonic treatment, taking out the PVDF film loaded with the nano-gold particles after the ultrasonic treatment is finished, and air-drying to obtain the nano-gold test paper film.
Specifically, a PVDF membrane with the diameter of 6mm is added into 2mL of the nano-gold solution prepared in the step S1 for ultrasonic treatment, the ultrasonic temperature is controlled to be 30-60 ℃, and the ultrasonic action time is controlled to be 20-140 min;
and after the reaction is finished, cooling to room temperature, taking out the nano gold test paper film, rinsing in ultrapure water, and naturally drying in air.
The optimal experimental conditions are obtained by adjusting the ultrasonic temperature and the ultrasonic action time respectively. Wherein, the experiment condition is optimized to ensure that AuNPs are uniformly distributed on the PVDF film, and the light intensity value expression on the PVDF film loaded with the nano-gold particles is analyzed by utilizing Image J software. The smaller the fluctuation of the light intensity value, the more uniform and stable the AuNPs load dispersion, and the more nonuniform the AuNPs load dispersion.
Optimizing ultrasonic temperature conditions:
adding 2mL of AuNPs into 4 centrifuge tubes and 2mL of centrifuge tubes respectively, sequentially adding 1 PVDF film with the diameter of 6mm into each centrifuge tube, placing the samples in ultrasonic cleaning machines with the temperature of 30, 40, 50 and 60 ℃ respectively for ultrasonic heating for 60 minutes, cooling to room temperature after the reaction is finished, taking out the paper sheets, rinsing in ultrapure water, air-drying and photographing, and analyzing the light intensity value by using Image J software.
Please refer to fig. 1, which is a naked eye visualization graph of the uniformity of AuNPs distribution on PVDF membrane under different ultrasonic temperature conditions. As can be seen from FIG. 1, with the rise of the ultrasonic temperature, the color of the gold nanoparticles in the solution gradually becomes lighter, which corresponds to the deepening of the test paper film, mainly because the color of the gold nanoparticles can reflect the concentration and the nature of the gold nanoparticles to a certain extent, so that the gold nanoparticles can be judged by naked eyes to be well loaded on the paper sheet when the temperature is 45-55 ℃.
However, due to certain errors and uncertainty in naked eye observation, after the processed paper is photographed, the light intensity numerical analysis is carried out on the color of the paper by using Image J software. The analysis result is shown in fig. 2, which is a light intensity value analysis chart of the uniformity degree of the AuNPs distribution on the PVDF film under different ultrasonic temperature conditions. As can be seen from FIG. 2, the light intensity fluctuates sharply at 25 ℃ and 35 ℃ due to the uneven color distribution in the local area, which indicates that the gold nanoparticles are not well fixed on the surface of the PVDF membrane; when the temperature rises to 45 ℃, the overall light intensity value does not fluctuate greatly any more, which shows that the gold nanoparticles are fixed on the test paper film uniformly; when the temperature rises to 55 ℃ again, the light intensity value basically does not change obviously any more,
the light intensity value analysis result is approximately consistent with the naked eye visual judgment. In this embodiment, the preferred ultrasound temperature is 45-55 ℃; more preferably, the sonication temperature is 45 ℃.
Optimizing the ultrasonic action time condition:
2mL of AuNPs are respectively added into 7 centrifuge tubes with 2mL, then 1 PVDF film with the diameter of 6mm is sequentially added, the samples are placed at the optimal reaction temperature (45 ℃), the ultrasonic time is 20, 40, 60, 80, 100, 120 and 140min in sequence, after the reaction is finished, the samples are cooled to the room temperature, the paper sheets are taken out, rinsed in ultrapure water, air-dried and photographed, and the light intensity value of the samples is analyzed by Image J software.
Please refer to fig. 3, which is a naked eye visualization graph of the uniformity of AuNPs distribution on PVDF membrane under different sonication time conditions. As can be seen from FIG. 3, in the range of 20-100min, the color of the nano-gold solution observed with naked eyes is not changed greatly with the extension of the ultrasonic time, but the color distribution of the corresponding paper is gradually uniform, the color becomes obviously lighter in 100min, the color of the paper is most uniform, and when the time is continuously increased, the color of the solution and the color of the paper are not changed greatly.
And similarly, carrying out light intensity numerical analysis on the color of the test paper film by using Image J software to determine the influence of the ultrasonic action time on the uniformity of the gold nanoparticles on the PVDF film. The light intensity value analysis is carried out on the processed nano gold paper film by adopting the same processing method as the ultrasonic temperature, the analysis result is shown as figure 4, and the light intensity value analysis figure is the light intensity value analysis figure of the uniform degree of AuNPs distributed on the PVDF film under different ultrasonic action time conditions.
As can be seen from FIG. 4, the ultrasonic action time reaches 80min, and the light intensity value does not fluctuate greatly any more. In this embodiment, the preferred ultrasound action time is 80-140 min; more preferably, the sonication time is 100 min.
Then, the detection principle of the nano gold test paper film applied to chloride ion detection is explained.
Strong acidGold (Au) cannot be dissolved, so AuNPs cannot be dissolved either. However, in HNO3And Cl-The nitrosyl chloride (NOCl) generated under the combined action of the two can dissolve AuNPs, mainly the NOCl has stronger oxidizing capability than concentrated nitric acid, Au in the AuNPs can lose electrons and be oxidized, and meanwhile, high-concentration Cl-Can form stable complex ions with metal ions thereof [ Au (Cl)x]-Thereby, the Au standard electrode potential in the AuNPs is reduced, and the reaction proceeds toward Au dissolution. The reaction equation is as follows:
HNO3+3HCl＝2H2O+Cl2+NOCl
Au+Cl2+NOCl＝AuCl+NO↑
AuCl3+HCl＝H[AuClx]
wherein x is 2 or 4, depending on Cl-Concentration, pH and nature of the oxidizing agent, the stability of the complex being dependent on AuNPs and Cl-Concentration and electrochemical potential of the system. Therefore, the gold nanoparticles loaded on the PVDF film are gradually etched to be complete along with the time, the color change can be identified by naked eyes, namely, the color is changed from red to fading, and then the Cl is changed through the change of the gray value-Visual detection of (2).
The feasibility of detecting chloride ions by the nanogold test paper film provided by the invention is analyzed through a specific experiment.
In order to prove the feasibility of the experiment for detecting chloride ions by the nano-gold test paper film, the prepared nano-gold test paper film is respectively placed in the following conditions: (1)1.25mL of concentrated nitric acid solution (12 mol/L); (2)1.25mL of sodium chloride standard solution (2%); (3)250 μ L of sodium chloride (2%) and 1mL of concentrated nitric acid (12mol/L) were mixed. And then respectively placing the films at room temperature for reaction for 55min, and observing the fading condition of the nano-gold test paper film.
Please refer to fig. 5, which is a color response diagram of the nano-gold test paper film under different reaction systems. Wherein a represents the color response of the nano-gold test paper film under a concentrated nitric acid solution reaction system; b represents the color response of the nano-gold test paper film under a sodium chloride standard solution reaction system; c represents the color response of the nano-gold test paper film under the condition of the reaction of the mixed solution of sodium chloride and concentrated nitric acidShould be used. As can be seen from fig. 5, when sodium chloride or concentrated nitric acid exists alone, the gold nanoparticles on the test paper film are not etched, so that the color is not changed; but when sodium chloride and concentrated nitric acid are present simultaneously, Cl--HNO3Etching the AuNPs system, and fading the test paper film, namely, the color change of the test paper film and Cl-The feasibility of detecting chloride ions by the nano-gold test paper film provided by the invention is proved.
Next, the application of the nanogold test paper film provided by the invention in chloride ion detection is explained in detail.
A method for detecting chloride ions comprises the following steps:
step S1: mixing a sample to be detected with a nitric acid solution;
step S2: adding the nanogold test paper film into the mixed solution obtained in the step S1, reacting for 5-75min, and qualitatively detecting chloride ions when the nanogold test paper film fades;
and analyzing the light intensity value of the reacted nano gold test paper film through Image J software to obtain an optical signal of the nano gold test paper film, so as to realize quantitative detection of the concentration of the chloride ions in the solution to be detected.
The sensitivity detection and the selectivity determination of the nano-gold test paper membrane provided by the invention on chloride ions are described through specific experiments, and the optimized condition parameters in the detection process are obtained through the sensitivity detection.
And (3) sensitivity detection:
1. research on detection sensitivity of chloride ions by naked eye colorimetric method
A plurality of nanogold test paper films are taken and respectively added into sodium chloride and nitric acid solutions with different concentrations, and the color response of the mixed solution of the sodium chloride and the nitric acid with different concentrations to the nanogold test paper films is observed by naked eyes under the condition of natural light, as shown in figure 6.
As can be seen from fig. 6, when sodium chloride and nitric acid exist alone, the color of the nanogold test paper film does not change, indicating that the etching oxidation of the nanogold particles is not caused by the oxidation of the nitric acid;
when the concentration of nitric acid is between 0 and 1mol/LThe color of the nano-gold test paper film hardly changes with the increase of the concentration of sodium chloride, and the analysis probably results from the fact that the nitric acid concentration is low and can not provide enough NO3 -Therefore, insufficient NOCl is caused to oxidize the gold Nanoparticles (NO)3 -+Cl-→NOCl)；
When the concentration of nitric acid is increased to 3mol/L, the gold nano-particles can be obviously oxidized when the concentration of sodium chloride is 0.5%, and at the moment, the nano-gold test paper film presents the white color of the most original paper sheet.
In order to obtain better sensitivity, the concentration of the concentrated nitric acid is gradually increased, the detectable concentration of the sodium chloride is lower along with the continuous increase of the concentration of the nitric acid, the lower limit of the detection of the sodium chloride is not obviously changed after the concentration of the nitric acid reaches 9mol/L, and the analysis is probably due to NO3 -And Cl-The binding capacity of the test strip reaches the limit, so that no more NOCl is generated, or because the capacity of loading the nano-gold particles on the surface of the nano-gold test strip membrane is limited, enough NOCl can oxidize all the gold nanoparticles. Therefore, when the concentration of the sodium chloride reaches 0.01%, the detection limit is basically not changed even if the concentration of the nitric acid is increased.
The lower detection limit of naked eye detection is often very limited, and when the concentration of sodium chloride is reduced to 0.01%, the color of the gold nano test paper sheet hardly has any difference in the observation range of human eyes. And because of the sensitivity difference of light and color of human eyes under illumination, the final detection result has larger difference due to external factors such as light and the like and different observers, so the naked eye colorimetric method for detecting sodium chloride can only carry out qualitative detection but not quantitative analysis.
2. Research on detection sensitivity of chloride ions by light intensity value
In order to obtain the best sensitivity, the light intensity values obtained by the nano-gold test paper film and sodium chloride under different reaction times (5 min, 35min, 55min and 75min) are analyzed by using Image J. The analysis results are shown in fig. 7-10, wherein fig. 7 is a light intensity value analysis diagram of the nanogold test paper film under the condition of reacting for 5min in the mixed solution reaction system of sodium chloride and nitric acid with different concentrations; FIG. 8 is a light intensity value analysis diagram of the reaction of the nano-gold test paper film in the mixed solution reaction system of sodium chloride and nitric acid with different concentrations for 35 min; FIG. 9 is a light intensity analysis chart of the nanogold test paper film reacting for 55min in the mixed solution reaction system of sodium chloride and nitric acid with different concentrations; FIG. 10 is a light intensity analysis chart of the nanogold test paper film in the reaction system of the mixed solution of sodium chloride and nitric acid with different concentrations for 75 min.
As can be seen from fig. 7-10, when only nitric acid or sodium chloride exists, the light intensity value of the nano-gold test paper film does not change with the increase of time, and the phenomenon is basically consistent with the result observed by naked eyes;
by varying nitric acid and sodium chloride (Cl) with increasing reaction time-) The concentration of the gold nano test paper film can obtain gold nano test paper films with different colors, and the corresponding light intensity value can also change along with the change of the color, namely sodium chloride (Cl) under different conditions-) The concentration has an optimal reaction. Sodium chloride (Cl) observed with the naked eye at 5min when the nitric acid concentration is above 5mol/L-) The lowest limit is 1%, and when the light intensity value is used for analyzing the light intensity value, the lowest detection limit can reach 0.1%. Meanwhile, with the continuous increase of the concentration of the nitric acid, the lowest detection limit obtained through the light intensity value is 0.05%. Through research, AuNPs are found in HNO3And sodium chloride (Cl)-) In the presence of the same time, the infrared spectrum of the gold nanometer is shifted, and Au is simultaneously generated0Is also oxidized to Au3+；
Sodium chloride (Cl) resulting from the etching reaction as the reaction time increases-) The lower limit of detection is lower and lower, and sodium chloride (Cl) is added when the reaction time is 35min-) The minimum limit of (A) can reach 0.01%. Not only was the detection limit reduced by a factor of 5 relative to 5min, but the required nitric acid concentration was also reduced to 3mol/L at the lowest detection limit.
At 55min and 75min, the response degree of the sodium chloride on the nano-gold test paper film is gradually weakened, the sensitivity is basically not changed through light intensity value analysis, and NO needing to be provided at the moment3 -There was no difference in concentration, and thus sodium chloride (Cl) was analyzed-) At saturation, NO3 -The influence on the system is small.
In this embodiment, the optimum sensitivity can be achieved at a reaction time of 55 min.
And (3) selective determination:
in order to research the selectivity of the gold nano test paper sheet on chloride ions, under the same experimental conditions, the chloride ion standard solution is replaced by other interference ion solution (HSO) with higher concentration4 2-、I-、CH3COO-、Hg2+、Cu2+、Br-、F-、Pb2+) The concentration of chloride ions is 0.01 percent, the concentration of other ions is 0.1 percent, the gold nano-test paper sheet is added into the mixed solution of other ions and nitric acid, and after the reaction under the same condition is finished, the gold nano-test paper sheet is taken out, naturally dried and photographed.
Fig. 11 is a naked eye view showing selectivity of the nano-gold test paper film to chloride ions. As can be seen from fig. 11, when observed with the naked eye, the other interfering ions do not cause the change of the color of the nano-gold test paper film, while the chloride ions directly present an original white state, which indicates that the chloride ions have completely etched the nano-gold particles, while the other ions have almost no effect on the nano-gold test paper film. Therefore, the nano gold test paper film has better selectivity on chloride ions.
In conclusion, AuNPs are uniformly attached to the PVDF film through the auxiliary action of ultrasound so as to obtain a red AuNPs-PVDF nanogold test paper film with uniform color; and the detection method with good response to chloride ions is constructed based on the etching effect of the nano-gold particles in the nitric acid solution by the chloride ions. The Image J is used for analyzing the light intensity value of the reacted picture to obtain an optical signal of the reacted picture, so that the chloride ions can be rapidly detected, and the detection method of the chloride ions provided by the invention has good sensitivity.
The detection method of chloride ions provided by the invention can be applied to the detection of the concentration of sodium chloride, such as the detection of the content of sodium chloride in food; the method can also be applied to the concentration detection of other chloride salts.
The embodiments of the present invention are described in detail above with reference to the drawings, but the present invention is not limited to the described embodiments. Various changes, modifications, substitutions and alterations to these embodiments will occur to those skilled in the art without departing from the spirit and scope of the present invention.

Claims (5)

1. The application of the nanogold test paper membrane in chloride ion detection is characterized in that a sample to be detected is mixed with a nitric acid solution, the nanogold test paper membrane is added, the chloride ion content in the sample is detected according to the color change of the test paper membrane, and the nanogold test paper membrane is prepared by loading nanogold particles on the surface of a PVDF membrane.
2. A method for detecting chloride ions is characterized by comprising the following steps:
step S1: mixing a sample to be detected with a nitric acid solution;
step S2: and (3) loading nano gold particles on the surface of the PVDF membrane to prepare a nano gold test paper membrane, adding the nano gold test paper membrane into the mixed solution obtained in the step S1, reacting for 5-75min, and qualitatively detecting chloride ions when the nano gold test paper membrane fades.
3. The method for detecting chloride ions according to claim 2, wherein step S2 further comprises: and analyzing the light intensity value of the reacted nano gold test paper film through Image J software to obtain an optical signal of the nano gold test paper film, so as to realize quantitative detection of the concentration of the chloride ions in the solution to be detected.
4. The method according to claim 2, wherein the concentration of the nitric acid solution in step S1 is 3 to 9 mol/L.
5. The method according to claim 2, wherein the reaction time in step S2 is 55 min.
CN201810591101.9A 2018-06-10 2018-06-10 Nano gold test paper film and application thereof in chloride ion detection Active CN108776133B (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103822889A (en) * 2014-01-15 2014-05-28 江南大学 Colorimetric detection method for Cl<->, Br<-> and I<-> based on silver nano-cluster hydrogel
CN104990918A (en) * 2015-07-16 2015-10-21 重庆大学 Test paper film based on nanogold and method for detecting lead ion by test paper film
KR20170092188A (en) * 2016-02-03 2017-08-11 동국대학교 산학협력단 Rapid diagnostic kit using Immunochromatography for Food hypersensitivity and use thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103822889A (en) * 2014-01-15 2014-05-28 江南大学 Colorimetric detection method for Cl<->, Br<-> and I<-> based on silver nano-cluster hydrogel
CN104990918A (en) * 2015-07-16 2015-10-21 重庆大学 Test paper film based on nanogold and method for detecting lead ion by test paper film
KR20170092188A (en) * 2016-02-03 2017-08-11 동국대학교 산학협력단 Rapid diagnostic kit using Immunochromatography for Food hypersensitivity and use thereof

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Electrospun Polymer Nanofibers Decorated with Noble Metal Nanoparticles for Chemical Sensing;Chen Chen et al;《Nanoscale Research Letters》;20171231;第12卷;全文 *
Enhanced catalytic degradation of 4-NP using a superhydrophilic PVDF membrane decorated with Au nanoparticles;Ziyang Wu et al;《RSC Adv.》;20161231;第6卷;2.2 Synthesis of AuNPs、2.4 Preparation of the Au–PDA–PVDF membranes、 *

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