Determination of tin in steels by non-dispersive atomic fluorescence spectrometry coupled with flow-injection hydride generation in the presence of L-cysteine

摘要

Flow-injection hydride generation has been coupled with a non-dispersive atomic fluorescence spectrometer for the determination of trace concentrations of tin. The use of L-cysteine in stannane generation enhances the atomic fluorescence signal for tin. In addition, it appears that the flow-injection method allows the use of a wider range of acid concentrations, and hence interference from transition elements is also reduced. An absolute detection limit of 1.3 ng was achieved with a 0.5 ml sample. Ten determinations of a solution containing 100 ng ml~(-1) of tin(H) generated a relative standard deviation of 1.8%. The linear dynamic range of the calibration curve extended over three orders of magnitude and sample throughput rate was 144 samples h~(-1). Application of the proposed technique is demonstrated by the determination of tin in low alloy steel standard reference materials.