Revolutionizing silver quantification: a novel ternary surfactant system with 2-nitro-6-(thiazol-2-yl-diazenyl)phenol and Triton X-100 for enhanced spectrophotometric analysis

Abstract

Although modern reported methods, such as AAS, ICP-AES, ICP-MS, have good sensitivity, the high cost of equipment, the need for sophisticated instruments, separation and preconcentration steps and experienced technicians along with lack of precise methods make them cumbersome. Solid phase extraction (SPE) emerges as an attractive technique that reduces solvent consumption, minimizes exposure, shortens extraction time, and lowers disposal costs. Herein, a pioneering methodology for the quantification of minute amounts of silver is introduced, using 2-nitro-6-(thiazol-2-yl-diazenyl)phenol (NTDP) as a complexing agent and Triton X-100 as a nonionic surfactant within a ternary surfactant system at a pH of 5.3. This novel extraction strategy demonstrated selective preconcentration. The enriched solution was subjected to spectrophotometric analysis for the quantification of the analyte. After refining extraction and complexation parameters, a remarkable 250-fold increase in the enrichment factor was attained, highlighting a sensitivity boost of 509 times compared with traditional extraction approaches relying solely on nonionic surfactants. The key parameters of molar absorptivity and Sandell sensitivity were determined to be 6.04 × 10⁶ L mol⁻¹ cm⁻¹ and 0.0018 ng cm⁻², respectively. The calibration plot was observed from 5.0–175 ng mL⁻¹, whereas Ringbom optimum concentrations ranged from 15–160 ng mL⁻¹. The detection and quantification limits were 1.63 and 4.95 ng mL⁻¹, respectively. The relative standard deviation (RSD) of the complex was 2.27. The suggested method was efficiently utilized for assessing the Ag⁺ concentration in real samples, producing acceptable outcomes.