Silver and gold nanocluster catalyzed reduction of methylene blue by arsine in micellar medium

Arsenic can be determined in parts-per-million (ppm) level by absorbance measurement. This method is based on the quantitative colour bleaching of the dye, methylene blue by arsine catalyzed by nanoparticles in micellar medium. The arsine has been generated in situ from sodium arsenate by NaBH₄ reduction. The absorbance measurement was carried out at the λ_max of the dye at 660 nm. The calibration graph set-up for three linear dynamic ranges (LDR) are 0-8.63 ppm, 0-1.11 ppm and 0-0.11 ppm and limit of detections (LODs) are 1.3, 0.53 and 0.03 ppm, respectively. This method is simple, sensitive and easy to carry out. It is free from phosphate and silicate interference and applicable to real sample analysis.