DETERMINATION OF OXALATE IN VEGETABLE SAMPLES USING A LOW COST ELECTRODE BY POTENTIOMETRIC MICROTRITRATION METHOD
The purpose of this research was to build a potentiometricmicrotitration system by using homemade low cost electrodes (a pencil carbon electrode as a working electrode and a silver/silver chloride (Ag/AgCl) electrode as a reference electrode) for determination of oxalate. The analysis was based on a redox reaction of the oxalate (titrand) in sulfuric acid solution was titrated with a few microliter of 0.02 mol L-1 potassium permanganate solution (titrant). The conditions such as electroplating time of silver stripe in saturated potassium chloride solution, concentration and volume of sulfuric acid and temperature of titration system were studied. The results were 9 min of electroplating time, 2.0 mol L-1 and 1 mL of sulfuric acid and titration at room temperature. This proposed method was applied for the determination of oxalate in some vegetable samples. It provided some advantages of low cost of instruments and analysis, simple system and operation, low chemical consumption, low toxic waste and environmental friendly. It was found that the results obtained from the proposed method were good accuracy and precision.
Charoenkiatkul, S., Wasantwisut, E., Rojroongwasinkul, N., Judprasong, K. & Kettawan, A. (2004). Study of calcium bioavailability in selected Thai food by estimation from chemical composition. Research report submitted to Thailand Research Fund.
Chongchaithet, N. (2006). Kerd Khwam ru reuang oxalate. Bureau of Nutrition (BoN), Department of Health, Ministry of Public Health. (in Thai)
Hu, H.C., Jin, H.J. & Chai, X.S. (2014). A practical headspace gas chromatographic method for the determination of oxalate in bleaching effluents. Journal of Industrial and Engineering Chemistry. 20, 13-16.
Khiawsaart, K., Jaidee, P., Ramangthong, J. (2013). Determination of ethanol in alcoholic beverage by a microscale potentiometric redox titration. Bachelor of Science Program in Chemistry. Faculty of Science and Technology,
Nakhon Sawan Rajabhat University. (in Thai)
Kusuma, D.S., Vanhanen, L.P. & Savage, G.P. (2016). Evaluation of extraction parameters for total oxalate determination in spinach using design of experiment analysis. Journal of Food Composition and Analysis. 51, 9-14.
Nakorn, B. (2003). Determination of Oxalic acid in Thai vegetables by Precipitation of Calcium Oxalate. Ubonratchatani : Faculty of Science and Technology, Ubonratchatani Rajabhat University. (in Thai)
Nelson, B.C., Rockwell, G.F., Campfield, T., O’Grady, P., Hernandez, R.M. & Wise, S.A. (2000). Capillary electrophoretic determination of oxalate in amniotic fluid. Analytica Chimica Acta. 410, 1-10.
Nguyên, H.V.H., Lê, H.M. & Savage, G.P. (2018). Effects of maturity at harvesting and primary processing of cocoa beans on oxalate contents of cocoa powder. Journal of Food Composition and Analysis. 67, 86-90.
Piwpuan, N. (2014). Calcium oxalate crystals and oxalate content in some vegetables from Nong Khai Province. KKU Science Journal. 42(4), 820-829. (in Thai)
Pourreza, N., Lotfizadeh, N. & Golmohammadi, H. (2018). Colorimetric sensing of oxalate based on its inhibitory effect on the reaction of Fe(III) with curcumin nanoparticles. Spectrochimica Acta Part A: Molecular and Biomolecular
Spectroscopy. 192, 251-256.
Shi, L., Arntfield, S.D. & Nickerson, M. (2018). Changes in levels of phytic acid, Lectins and oxalates during soaking and cooking of Canadian pulses. Food Research International. 107, 660-668.
Sriboonlue, P., Prasongwatana, V. & Suwanatrai, S. (1994). Calcium oxalate content of vegetables frequently consumed in Khon Kaen province. Khon Kaen: Khon Kaen University. (in Thai)
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