TH15531Y - A system for the electrochemical measurement of salicylic acid in food, the testing procedure, and the instruments or equipment for such measurement. - Google Patents

Abstract

------04/01/2562------(OCR) Page 1 of 1. Summary of the Invention. The system for measuring salicylic acid in food using the differential pulse voltammetry technique consists of a screen-printed probe, a two-electrode system comprising a carbon working electrode and a silver/silver chloride (Ag/AgCl) reference electrode. The chemicals used to control pH changes during salicylic acid measurement in the sample are 0.4 M Briston-Robinson buffer solution with a pH of 2.0-11.0. The electrolyte used is a 0.01-0.1 M salt solution. The conditions for differential pulse voltammetry are a potential change rate of 0.02 volts, an interval time of 0.7 seconds, and a modulation amplitude of 0.15 volts in the potential range of 0.4-1.5 volts. ------20/07/2561------(OCR) Page 1 of 1. Abstract of the Invention: A system for the detection of salicylic acid in food using the electrochemical method of differential pulse voltammetry. It consists of a screen-printed probe which is a bielectrode type consisting of a carbon working electrode and a reference electrode made of silver/silver chloride (Ag/AgCl). The chemicals used to control the changes in acidity and alkalinity during the measurement of salicylic acid from the sample to be measured are 0.4 molar Bristol-Robinson buffer solutions, pH 2.0-11.0. The electrolyte solution used for measurement is a salt solution with a concentration of 0.01-0.1 molar. The conditions used for electrochemical measurement using differential pulse voltammetry are a potential change rate of 0.02 volts, an interval time of 0.7 seconds, and a modulation amplitude of 0.15 volts at a potential range of 0.4-1.5 volts. ------20/10/2017------(OCR) Page 1 of 1. Summary of the Invention: Salicylic acid is useful in inhibiting the growth of microorganisms, and therefore, its contamination is continuously found in pickled vegetables and fruits. This invention reveals a system for the electrochemical measurement of salicylic acid in food, the measurement method, and the instrument or device for such measurement. The sample preparation and measurement procedures are simple and convenient for the user, requiring no expert knowledge, while maintaining high accuracy and precision. The system for the measurement of salicylic acid... The detection of salicylic acid in food using the differential pulse voltammetry (DPV) technique involves a screen-printed probe consisting of a dual-electrode system: a carbon working electrode and a silver/silver chloride (Ag/AgCl) reference electrode. The chemical used to control pH changes during salicylic acid analysis is a 0.4 M Briston-Robinson buffer solution with a pH of 2.0-11.0. The electrolyte used is a 0.01-0.1 M salt solution. The electrochemical conditions used for differential pulse voltammetry are a potential change rate of 0.02 volts, an interval time of 0.7 seconds, and a modulation amplitude of 0.15 volts in the potential range of 0.4-1.5 volts.

Claims (7)

------04/01/2019------(OCR) Page 1 of 2 pages Claims1. The system for the detection of salicylic acid in food using the electrochemical method consists of: a. Power supply (1) which converts 220 volt AC current to 12 volt DC and 5 volt DC current to supply other devices in the instrument. b. Electrical control and current response measurement unit (2) which controls the electrochemical cell system using differential pulse voltammetry technique and measures the current generated from the oxidation reaction of salicylic acid. Inside it consists of: * Electrochemical control unit (STU-250 EC) (3) which controls the current supply. It is supplied as pulses at the electrodes with an interval time of 0.7 seconds, a modulation amplitude of 0.15 volts, at a potential range of 0.125 volts, and has a connection to * a screen-printed probe (4) which is a bielectrode probe consisting of - a carbon working electrode (5) which is the electrode that undergoes oxidation of the salicylic acid being measured - a reference electrode made of silver/silver chloride (Ag/AgCl) (6) which is responsible for controlling the potential supplied to the probe to a constant value. C. The signal processing and analysis unit (7) receives current data from the electrical control unit and measures the current response (2) to analyze against the equations entered into the device to calculate the amount of salicylic acid contamination in the sample and displays the result on the screen in milligrams per kilogram. D. The chemicals used in the system. The chemicals used in the preparation of the mixture to be dropped onto the screen printing probe (4) for the detection of salicylic acid consist of: - The chemicals used to extract salicylic acid from the sample to be detected and to control the changes in acidity and alkalinity during the detection of salicylic acid from the sample to be detected. In this invention, it is a 0.4 molar Bristol-Robinson buffer solution, pH 2.0 - 11.0, with an optimal extraction pH of pH 2.0. The ratio of 2 pages of the food sample to the appropriate Bristol-Robinson buffer solution is 1:15-1:20, or the optimal is 1:20. - The electrolyte solution used for detection, mixed with the sample to be detected in this invention, is a salt solution, which can be selected from potassium chloride solution, sodium chloride solution. Either individually or in combination, more than one concentration of 0.01-0.1 molar and the most suitable electrolyte solution used for measurement is 0.05 molar sodium chloride. A special feature is the electrochemical control unit, model STU-250 EC 3, which controls the current supply. The conditions used for electrochemical measurement using differential pulse voltammetry are a potential change rate of 0.02 volts at an interval time of 0.7 seconds and a modulation amplitude of 0.15 volts in the voltage range of 0.4 - 1.5 volts. ------20/07/2018------(OCR) Page 1 of 3. Claims 1. The system for electrochemical measurement of salicylic acid in food, the measurement procedure, and the instrument or equipment for such measurement consist of: a. Power supply 1, which converts 220-volt AC current to 12-volt and 5-volt DC current to power other components within the instrument. b. Electrical control and current response measurement unit 2, which controls the electrochemical cell system using differential pulse voltammetry technique and measures the current generated by the process. The oxidation reaction of salicylic acid is performed using the following internal components: * Electrochemical control unit (STU-250 EC) 3, which controls the current supply by delivering pulses to the electrodes with an interval time of 0.7 seconds, a modulation amplitude of 0.15 volts, and a potential range of 0.125 volts. It also has a connection to a screen-printed probe 4, a bielectrode probe consisting of: - A carbon working electrode 5, where the oxidation of the measured salicylic acid occurs; - A silver/silver chloride (Ag/AgCl) reference electrode 6, which maintains a constant potential supplied to the probe. C. Signal processing and analysis unit 7, which receives current data from the control unit. The device uses electricity and measures the electrical response to analyze the sample against the equations entered into the device to calculate the amount of salicylic acid contamination in the sample. The result is displayed on the screen in milligrams per kilogram. A special feature is the electrochemical control unit, model STU-250 EC, which controls the electrical current supply. The conditions used for electrochemical measurement with differential pulse voltammetry are a potential change rate of 0.02 volts at an interval time of 0.7 seconds and a modulation amplitude of 0.15 volts in the range of 0.4-1.5 volts. Page 2 of 3. 2. System for the electrochemical measurement of salicylic acid in food, measurement procedure, and instrument or equipment for such measurement, as per claim 1, which has the following operating steps: *Prepare the food sample to be measured for salicylic acid. *Salicylic acid content is measured using a screen-printed probe. *The electrochemical control unit, model STU-250 EC, generates an electrical signal using differential pulse voltammetry according to the set parameters and reads the electrochemical signal of the oxidation reaction, reducing noise. *The signal processing and analysis section records the signal and displays it on the screen as salicylic acid content in ppm. It can be adjusted to display the result as a voltamogram and can be adjusted to select the height of the oxidation peak and calculate the result to interpret as salicylic acid concentration on the screen. The display and control section (Human interface and controller) is a touch screen consisting of measurement command buttons and a measurement display section. 3. System for the electrochemical measurement of salicylic acid in food, the measurement method, and the instrument or equipment for such measurement, as per claim 1, where the chemicals used in the control. The change in acidity and alkalinity during the measurement of salicylic acid from the sample to be measured is due to the use of a 0.4 M Bristol-Robinson buffer solution with an optimal extraction pH of 2.0. 4. The system for the electrochemical detection of salicylic acid in food, the detection method, and the instrument or device for such detection as per claim 1, where the optimal electrolyte solution used for the detection is 0.05 M sodium chloride. 5. The system for the electrochemical detection of salicylic acid in food, the detection method, and the instrument or device for such detection as per claim 1, where the optimal ratio of the food sample used for detection to the Bristol-Robinson buffer solution is 1:15-1:20, or the optimal ratio is 1:20. 6. The system for the electrochemical detection of salicylic acid in food, the detection method, and the instrument or device for such detection as per claim 1. According to Claim 1, which is applied to the measurement, page 3 of 3, the total salicylic acid content in fresh and processed foods is measured in concentrations of ppm (ppm). ------20/10/2017------(OCR) Page 1 of 2, Claim. 1. The system for electrochemical detection of salicylic acid in food consists of: a. A screen-printed electrode, a bielectrode type electrode consisting of: - A carbon working electrode, which undergoes oxidation of the salicylic acid being measured. - A silver/silver chloride (Ag/AgCl) reference electrode, which maintains a constant voltage applied to the electrode. b. The electrochemical technique used for detection is differential pulse voltammetry. c. The chemical used to control changes in acidity and alkalinity during salicylic acid measurement in the sample is 0.4 M Briston-Robinson buffer solution, pH 2.0-11.0. d. The electrolyte solution used for detection is a salt solution, which can be either potassium chloride or sodium chloride, individually or in combination, with a concentration of 0.01-0.1 M. The special characteristics of this solution are... The conditions used for electrochemical measurements using differential pulse voltammetry are a potential change rate of 0.02 volts at an interval time of 0.7 seconds and a modulation amplitude of 0.15 volts in the voltage range of 0.4 - 1.5 volts. 2. A system for the electrochemical detection of salicylic acid in food, as per claim 1, whereby the chemical used to control the changes in acidity and alkalinity during the measurement of salicylic acid from the sample to be measured is a 0.4 M Bristol-Robinson buffer solution with an optimal extraction pH of 2.0. 3. A system for the electrochemical detection of salicylic acid in food, according to claim 1, where the optimal electrolyte solution for detection is 0.05 molar sodium chloride. Page 2 of 2. 4. A system for the electrochemical detection of salicylic acid in food, according to claim 1, where the optimal ratio of the food sample to the Bristol-Robinson buffer solution is 1:15-1:20, or the optimal ratio is 1:20. 5. A system for the electrochemical detection of salicylic acid in food, as per claim 1, which utilizes a disposable, screen-printed probe consisting of two electrodes: a working electrode made of carbon and a reference electrode made of silver/silver chloride (Ag/AgCl), requiring a small sample volume in the microliter range. 6. A system for the electrochemical detection of salicylic acid in food, as per claim 1, which is applied to measure the total salicylic acid content in fresh and processed foods, expressed in ppm (pm) concentrations. 7. The instrument or device for measuring salicylic acid in food consists of a system for measuring salicylic acid using the electrochemical method according to Patent 1, which includes the following components: a) power supply, b) electrical control and current response measurement unit, c) signal processing and analysis unit. The operating procedure is as follows: 1) Generating an electrical signal using differential pulse voltammetry techniques according to the set parameters, 2) Reading the electrochemical signal of the oxidation reaction and reducing noise, 3) Recording the signal and displaying it on the screen as the amount of salicylic acid in ppm, and it can be adjusted to display as a voltramogram, 4) Adjusting the set to select the height of the oxidation peak and calculating and interpreting the result as the salicylic acid concentration on the screen, d) Display and input unit (Human interface and controller), which is a touch screen system consisting of measurement command buttons and a measurement display unit.