摘要
A very sensitive electrochemical procedure for trace determination of copper and tin in the presence of lead using cathodic adsorption voltammetry is presented.The complex of copper,tin with salicylfluorone (SAF) is adsorbed on the hanging mercury drop electrode (HMDE) and the reduction current of the accumulated complex is measured by voltammetry.This method achieves the simultaneous determination of copper and tin,and has been applied to determine canned food.Anodic stripping voltarnmetry (ASV)is an effeCtive electroanajytital technique for themeasurement Of trace metal ions.But there are serious interferences due to overlapping strippingpeak and forming of intermetamc complex in complicated syStem.The results are usUally notsatisfaCtory. The dffeulty of simultaneous determination Of copper and tin in the presence of leadis the strong tendency of tin (IV ) species to hydrolyZO and polwnerise as well as the overlap ofthe stripping Peaks of tin and lead by anodic stripping voltarnmetry at mercury electrodes. Inaddition, tin and copper easily created into intermetailic complex on HMDE and the tin peak isrestrained by copper;it is very dimcult to determine them,individually or simultaneously.Various approaches have been employed to improve the selectivity of tin measurement bystripping voltammetry.These include prior separation['J, flow or medium--exchange schemes[23 orthe addtion Of surfactants' L3) We have determined Zr[4), Ga[sj, V['J, Sb[7) etc,by Cathodicstripping VOltammetry (csv) using nuorone claSs ligand as complexing agent.In this paper, wereport a hashly sensitive and selective stripping approach for sdriultaneous determination of copperand tin in the presence of lead' The method has been used to sampled of canned food.
A very sensitive electrochemical procedure for trace determination of copper and tin in the presence of lead using cathodic adsorption voltammetry is presented.The complex of copper,tin with salicylfluorone (SAF) is adsorbed on the hanging mercury drop electrode (HMDE) and the reduction current of the accumulated complex is measured by voltammetry.This method achieves the simultaneous determination of copper and tin,and has been applied to determine canned food.Anodic stripping voltarnmetry (ASV)is an effeCtive electroanajytital technique for themeasurement Of trace metal ions.But there are serious interferences due to overlapping strippingpeak and forming of intermetamc complex in complicated syStem.The results are usUally notsatisfaCtory. The dffeulty of simultaneous determination Of copper and tin in the presence of leadis the strong tendency of tin (IV ) species to hydrolyZO and polwnerise as well as the overlap ofthe stripping Peaks of tin and lead by anodic stripping voltarnmetry at mercury electrodes. Inaddition, tin and copper easily created into intermetailic complex on HMDE and the tin peak isrestrained by copper;it is very dimcult to determine them,individually or simultaneously.Various approaches have been employed to improve the selectivity of tin measurement bystripping voltammetry.These include prior separation['J, flow or medium--exchange schemes[23 orthe addtion Of surfactants' L3) We have determined Zr[4), Ga[sj, V['J, Sb[7) etc,by Cathodicstripping VOltammetry (csv) using nuorone claSs ligand as complexing agent.In this paper, wereport a hashly sensitive and selective stripping approach for sdriultaneous determination of copperand tin in the presence of lead' The method has been used to sampled of canned food.
