Grupo de Química Verde Coloidal e Macromolecular, Departamento de Química, Centro de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa, Av. P.H. Rolfs s/n, Viçosa, MG 36560-000, Brazil.
Talanta. 2010 Jan 15;80(3):1139-44. doi: 10.1016/j.talanta.2009.08.039.
A greener and more sensitive spectrophotometric procedure has been developed for the determination of phenol and o-cresol that exploits an aqueous two-phase system (ATPS) using a liquid-liquid extraction technique. An ATPS is formed mostly by water and does not require organic solvent. Other ATPS components used in this study were the polymer, polyethylene oxide, and some salts (i.e., Li(2)SO(4), Na(2)SO(4) or K(2)HPO(4)+KOH). The method is based on the reaction between phenol, sodium nitroprusside (NPS) and hydroxylamine hydrochloride (HL) in an alkaline medium (pH 12.0), producing the complex anion Fe(2)(CN)(10) that spontaneously concentrates in the top phase of the system. The linear range was 1.50-500microgkg(-1) (R>or=0.9997; n=8) with coefficients of variation equal to 0.38% for phenol and 0.30% for o-cresol (n=5). The method yielded limits of detection (LODs) of 1.27 and 1.88microgkg(-1) and limits of quantification (LOQs) of 4.22 and 6.28microgkg(-1) for phenol and o-cresol, respectively. Recoveries between 95.7% and 107% were obtained for the determination of phenol in natural water and wastewater samples. In addition, excellent agreement was observed between this new ATPS method and the standard 4-aminoantipyrine (4-AAP) method.
一种更绿色、更灵敏的分光光度法已被开发用于测定苯酚和邻甲酚，该方法利用水相双相体系（ATPS）结合液液萃取技术。ATPS 主要由水组成，不需要有机溶剂。本研究中使用的其他 ATPS 成分是聚合物聚氧化乙烯（PEO）和一些盐（如 Li(2)SO(4)、Na(2)SO(4)或 K(2)HPO(4)+KOH）。该方法基于在碱性介质（pH 12.0）中苯酚、硝普酸钠（NPS）和盐酸羟胺（HL）之间的反应，生成在体系的上相中自发浓缩的Fe(2)(CN)(10)络阴离子。线性范围为 1.50-500μgkg(-1)（R>或=0.9997；n=8），苯酚和邻甲酚的变异系数分别为 0.38%和 0.30%（n=5）。该方法对苯酚和邻甲酚的检出限（LOD）分别为 1.27 和 1.88μgkg(-1)，定量限（LOQ）分别为 4.22 和 6.28μgkg(-1)。在天然水和废水样品中测定苯酚的回收率在 95.7%至 107%之间。此外，这种新的 ATPS 方法与标准的 4-氨基安替比林（4-AAP）方法之间具有极好的一致性。
