Kiradzhiyska Denitsa, Milcheva Nikolina, Ruzmanova Miglena, Genç Fatma, Racheva Petya, Gavazov Kiril
Research Institute at the Medical University of Plovdiv, 15A, Vassil Aprilov Blvd., 4002 Plovdiv, Bulgaria.
Department of Chemical Sciences, Faculty of Pharmacy, Medical University of Plovdiv, 120 Buxton Bros Str., 4004 Plovdiv, Bulgaria.
Molecules. 2025 Aug 6;30(15):3287. doi: 10.3390/molecules30153287.
A novel centrifuge-less cloud point extraction (CL-CPE) method was developed for the spectrophotometric determination of copper(II) using 4-nitrocatechol (4NC) as the chelating agent. The extraction system utilizes a mixed micellar phase composed of the nonionic surfactant Triton X-114 and the ionic liquid (IL) Aliquat 336 (A336). The extracted ternary ion-association complex, identified as (A336)[Cu(4NC)], exhibits a maximum absorbance at 451 nm, with a molar absorption coefficient of 8.9 × 10 M cm and a Sandell's sensitivity of 0.71 ng cm. The method demonstrates a linear response in the copper(II) concentration range of 32-763 ng mL and a limit of detection of 9.7 ng mL. The logarithmic extraction constant (log ) was determined to be 7.9, indicating efficient extraction. Method performance, evaluated by the Blue Applicability Grade Index (BAGI) and the Click Analytical Chemistry Index (CACI), confirmed its feasibility, practicality, simplicity, convenience, cost-effectiveness, environmental friendliness, and analytical competitiveness. The proposed IL-CL-CPE method was successfully applied to the analysis of a dietary supplement, a solution for infusion, and synthetic mixtures simulating various copper alloys.
开发了一种新型的无离心浊点萃取（CL-CPE）方法，用于以4-硝基邻苯二酚（4NC）为螯合剂分光光度法测定铜（II）。萃取体系采用由非离子表面活性剂Triton X-114和离子液体（IL）Aliquat 336（A336）组成的混合胶束相。萃取得到的三元离子缔合物，鉴定为（A336）[Cu（4NC）]，在451nm处有最大吸收，摩尔吸收系数为8.9×10 M cm，桑德尔灵敏度为0.71 ng cm。该方法在铜（II）浓度范围为32-763 ng mL时呈线性响应，检测限为9.7 ng mL。对数萃取常数（log ）测定为7.9，表明萃取效率高。通过蓝色适用性等级指数（BAGI）和点击分析化学指数（CACI）评估的方法性能证实了其可行性、实用性、简单性、便利性、成本效益、环境友好性和分析竞争力。所提出的IL-CL-CPE方法成功应用于膳食补充剂、输液溶液和模拟各种铜合金的合成混合物的分析。
