A colorimetric method for the determination of isoprenaline sulphate in pharmaceutical preparations
A rapid and convenient colorimetric method is described for the determination of isoprenaline sulphate in pharmaceutical preparations. This method is based on measuring the intensity of the orange colour developed when isoprenaline sulphate is allowed to react with thiosemicarbazide in an alkaline medium. Beer's law is obeyed in the concentration range 2·0–16·0 µg ml–1. Data on precision and accuracy are presented. As the catecholic function with unsubstituted adjacent positions is required for the development of the colour, the method is highly specific.