Determination of Silver in Human Hair by Ionic Liquid‐based Cold‐induced Aggregation Microextraction as a Solvent Extraction Method

We report on the determination of silver ion in human hair sample using ionic liquid cold‐induced aggregation combined with spectrophotometric detection. Parameters governing the extraction efficiency (such as concentration of ligand, volume of ionic liquid, pH, temperature, extraction time) were optimized and resulted in enrichment factor of 44.4 for silver ion. The calibration curve was linear with correlation coefficient (R²) of 0.999, in the concentration range from 1.0 to 20 ng mL^?1. The relative standard deviation is 2.3% (for n = 10), the limit of detection is 0.262 ng mL^?1, and relative recoveries in real samples were more than 93%.