Department of Medical Science, Amnatcharoen Campus, Mahidol University, Amnat Charoen 37000, Thailand.
Department of Chemistry and Center for Innovation in Chemistry, Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
Molecules. 2022 Sep 4;27(17):5697. doi: 10.3390/molecules27175697.
An ultrasound-assisted, one-pot cloud point extraction was developed for the determination of iron in vegetable samples by UV-Visible spectrophotometry. This method was based on the complexation of iron with an environmentally-friendly natural chelating agent extracted from Dyer fruit at pH 5.5 in the presence of Triton X-114. Reagent extraction, complexation, and preconcentration were performed simultaneously using ultrasound-assisted extraction at 45 °C. The surfactant-rich phase was diluted with ethanol and loaded through a syringe barrel packed with cotton that acted as a filter to trap the reagent powder. Analyte-entrapped on cotton was eluted using 0.1 mol·L nitric acid solution. Filtrate and eluate solutions were measured absorbance of the dark-blue product at 575 nm. Influential parameters for the procedure were investigated. Under the optimum experimental conditions, the calibration curve was linear, ranging from 0.1 to 1.0 mg·L with = 0.997. Limits of detection and quantification were 0.03 and 0.09 mg·L, respectively while precision values of intra-day and inter-day were less than 5%. Recovery at 0.5 mg·L ranged from 89.0 to 99.8%, while iron content in vegetable samples ranged from 2.45 to 13.36 mg/100 g. This method was cost-effective, reliable, eco-friendly, and convenient as a green analytical approach to determining iron content.
超声辅助- 单步浊点萃取- 分光光度法测定蔬菜中铁含量。该方法基于在 pH5.5 下，铁与从染料果中提取的环保型天然螯合剂在 Triton X-114 的存在下形成配合物。在 45°C 下，通过超声辅助萃取同时进行试剂萃取、络合和预浓缩。含表面活性剂的富相用乙醇稀释，并通过填充有棉花的注射器筒加载，棉花作为过滤器捕获试剂粉末。用 0.1mol·L 硝酸溶液洗脱吸附在棉花上的分析物。测定滤液和洗脱液在 575nm 处的暗蓝色产物吸光度。考察了该方法的影响因素。在最佳实验条件下，校准曲线呈线性，范围为 0.1-1.0mg·L，相关系数为 0.997。检出限和定量限分别为 0.03 和 0.09mg·L，日内和日间精密度均小于 5%。在 0.5mg·L 时的回收率为 89.0-99.8%，而蔬菜中铁的含量为 2.45-13.36mg/100g。该方法具有成本效益、可靠、环保和方便等优点，是一种绿色分析方法，可用于测定铁含量。
