Determination of trace tin in foods by single-sweep polarography

A new method for the determination of trace tin in a solution of oxalic acid–methylene blue by single-sweep polarography is developed. The mechanism for the polarographic waves and the conditions for determining tin are discussed in this report. The peak height is directly proportional to the concentration of tin (IV) over the range 2.0×10−8–1.0×10−6 g ml−1. The detection limit and the recovery of the method are 1.0×10−8 g ml−1 and 93–98%, respectively. The method was successfully employed for the determination of tin in juices of canned fruits.