Measuring the rate of release of metal ions

摘要

A method of measuring the relative rates of release of a target metal ion from two or more samples includes: (i) providing at least two aliquots of a solution including an indicator, the indicator having a color; (ii) dispersing a sample into each aliquot; and (iii) during step (ii), monitoring the color of the indicator in situ to determine the rates of release of the target metal ions from the samples relative to one another. Each sample includes at least one source of the target metal ion. The indicator contains zincon. The samples are oral care compositions selected from a toothpaste, a tooth gel, and a tooth powder. The target metal ion is selected from the stannous and zinc (II).

主权项

1. A method of measuring the relative rates of release of a target metal ion from two or more samples, each sample comprising at least one source of the target metal ion, which method comprises:
(i) providing at least two aliquots of a solution including an indicator, the indicator having a colour; (ii) dispersing each sample into one of the aliquots; and (iii) during step (ii), monitoring the colour of the indicator in situ to determine the rates of release of the target metal ion from the samples relative to one another; wherein the indicator comprises zincon; wherein each sample is an oral care composition selected from a toothpaste, a tooth gel, and a tooth powder; and wherein the target metal ion is selected from stannous or stannous and zinc (II) in combination.