LC-MS/MS Detected Lower Valued of Dexamethasone and Prednisolone in Powdered Herbal Medicines Sold in Tanzania.

Abstract

As a consequence of perceived quality and safety of herbal medicines in varied communities, adulteration of such medicines with synthetic drugs has become a growing global concern. This study assessed the adulteration of herbal medicines with dexamethasone and prednisolone using LC-MS/MS.The optimized method was used to confirm presence of conventional drugs (dexamethasone and/or prednisolone) in the fourteen samples suspected to be adulterated after screening with TLC. This method was validated by determining coefficient of determination, limit of detection and limit of quantitation. Coefficient of determination for dexamethasone and prednisolone were 0.95 and 0.97 respectively. The limit of detection for dexamethasone and prednisolone were 13.79 ppm and 10.81 ppm respectively. The limit of quantitation was 41 ppm and 32 ppm for dexamethasone and prednisolone respectively. The results indicated that all 14 samples were adulterated with either all or one of the two suspected adulterants. It was observed that, while both prednisolone and dexamethasone were detected in nine herbal medicines samples, one (1) sample was adulterated with dexamethasone alone and four (4) samples were adulterated with prednisolone alone. However, the dexamethasone and prednisolone adulterants were only detected but could not be quantified because they were below quantification limit. The optimized method meets the International Council for Harmonization (ICH) standards therefore can be used to confirm the presence of dexamethasone and prednisolone in herbal medicines.