Determination of free bismuth in pharmaceutical preparations containing colloidal bismuth pectin or colloidal bismuth pectin

摘要

The present invention relates toA method for measuring free bismuth in a colloidal bismuth pectin or colloidal bismuth pectin containing pharmaceuticalThis measuring method isAn ethanol aqueous solution with a volume concentration of 7 to 20% was added to the formulation of a colloidal bismuth pectin or colloidal bismuth pectin containing agentShake and disperse uniformlyAdd an ethanol solution with a volume concentration of less thanAfter shaking and dispersingAdd ethanol until the volume of ethanol in the dispersion reaches 30 toShake and disperse uniformlyGet a colloidal solutionClear and clearBy complexation titration method or ultraviolet spectrophotometryThe content of free bismuth in the formulation of colloidal bismuth pectin or colloidal bismuth pectin containing is calculated.Ethanol solution has excellent solubility for free bismuth, as well asColloidal bismuth pectin molecules are blocked to some extentThe dynamic release process of bismuth salt by colloidal bismuth pectin can be effectively prevented.In the present inventionFree bismuth is measured by dispersing colloidal bismuth pectin with ethanol aqueous solution.The measurement result of free bismuth is more accurate and reliable.