A new Schiff base ligand, bis [5-((4-nitrophenyl)azosalicylaldehyde)] (BNAS), was synthesized and a highly sensitive, selective and rapid method for the determination of silver ion was developed. It is based on the rapid extraction of silver(I) ion with BNAS adsorbed on octadecylsilica (C 18 ) membrane disk. The retained silver ion can be eluted from the disk with a minimal amount of thiosulfate solution and the silver determined with FAAS. Extraction efficiency and the influence of flow rates, type and smallest amount of stripping reagent and pH were investigated. The relative standard deviation for ten replicate extractions of silver from 1 L samples containing 2.5 mg of silver is 1.1%. The breakthrough volume for 2.5 mg of silver is 2500 mL. The effects of various cationic interferences on percent recovery of silver were studied. The re-use of a modified disk was tested and it was found that the use of the same disk modified with 7 mg of BNAS for at least ten times resulted in no change in the recovery of silver ion. The proposed method permitted large enrichment factors of about 160 and higher. The limit of detection of the proposed method is 10 ng L 21 and the method is applied to the recovery of Ag 1 from different water samples and radiology film.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.