Ensafi A A, Kazemzadeh A
College of Chemistry, Isfahan University of Technology, Iran.
Fresenius J Anal Chem. 2000 Jul;367(6):590-2. doi: 10.1007/s002160000355.
A new simple, sensitive and rapid catalytic-spectrophotometric method for the determination of oxalic acid has been described based on its catalytic effect on the redox reaction between dichromate and Brilliant cresyl blue in acidic media by means of a flow injection analysis method. The color change of Brilliant cresyl blue due to its oxidation was monitored spectrophotometrically at 625 nm. The calibration graph was linear in the range of 0.020-4.70 microg/mL oxalic acid with a limit of detection 0.005 microg/mL of oxalic acid. The relative standard deviation for ten replicate measurements of 0.020 microg/mL and 0.900 microg/mL was 2.2% and 1.7%, respectively. No serious interference was identified. Oxalic acid was determined in wastewater and in spinach by the proposed method with satisfactory results.
基于草酸在酸性介质中对重铬酸盐与灿烂甲酚蓝之间氧化还原反应的催化作用，采用流动注射分析法，描述了一种测定草酸的新的简单、灵敏且快速的催化分光光度法。通过分光光度法在625nm处监测由于灿烂甲酚蓝氧化引起的颜色变化。草酸校准曲线在0.020 - 4.70μg/mL范围内呈线性，草酸检测限为0.005μg/mL。0.020μg/mL和0.900μg/mL的十次重复测量的相对标准偏差分别为2.2%和1.7%。未发现严重干扰。采用所提出的方法测定了废水中和菠菜中的草酸，结果令人满意。
