Complementarity of UV-PLS and HPLC for the simultaneous evaluation of antiemetic drugs.

This work was dedicated to the development of a simple and direct multivariate UV spectrophotometric method for the simultaneous determination of three antiemetic drugs (ondansetron, dexamethasone and aprepitant) in a new organogel formulation developed for their simultaneous transdermal administration. This method that does not require separation of the drugs and sophisticated instrument will permit to control quality of this new transdermal form both during the optimization step and for a further routine control of this preparation at the pharmacy department of the hospital. Hence, a partial least squares regression model using the spectral data record from 260 to 288 nm and 5 components, has firstly been validated thanks to the evaluation of the REP% (under 7.9%) and secondly using an accuracy profile approach (acceptance limit of ±10%). Thereby, the method allows the quantitation of the drugs in the ranges (5-15 mg L(-1)), (4-8 mg L(-1)) and (20-50 mg L(-1)) for ondansetron, dexamethasone and aprepitant, respectively. An HPLC/UV reference method has also been developed. Optimal separation (2.52<Rs<9.49) of the three drugs and their internal standards has been obtained in less than 15 min with a C18 stationary phase using a gradient separation protocol. This method has been validated similarly for the quantitation of ondansetron, dexamethasone and aprepitant in the ranges (0.3-3.5 mg L(-1)), (0.2-10 mg L(-1)) and (3.5-35 mg L(-1)), respectively. Both methods used for quality control of an organogel pharmaceutical formulation, have shown recoveries between 95% and 105%, hence validating the UV/PLS method and the formulation preparation process. Lower limits of quantitation obtained with the HPLC/UV method will be in favor of its use for permeation studies.