The determination of bupropion hydrochloride in pharmaceutical dosage forms and biological fluids by analytical methods

Potentiometric, conductometric, UV-spectrophotometric and second derivative spectrophotometric methods which are developed for the determination of Bupropion Hydrochloride (BUP) in pharmaceutical tablets, TLC and HPLC methods which are developed for the determination of BUP in both pharmaceuticals and human plasma were described in this study. Two spectrophotometric methods were validated and the limit of detection (LOD) and quantitation (LOQ) of UV-spectrophotometry were 2.73x10-6 M and 8.26x10-6 M. Also, these parameters were determined as 8.20x10-7 M and 2.48x10-6 M for the second derivative spectrophotometry, respectively. Then, a stability indicating TLC method is developed for the determination of BUP in pharmaceutical tablets in which BUP was subjected to acidic and alkali hydrolysis, oxidation, photodegradation, dry heat and wet heat treatment and the method was fully validated. The mobile phase consisted of ethanol-chloroform-glacial acetic acid (30:10:1, v/v/v) was used and the LOD and LOQ values of the method were found as 10.41 ng.spot -1 and 34.71 ng.spot -1, respectively.Then, developed TLC method was applied to human plasma samples for the determination of BUP and high recovery almost about 87 % and high precision with low % RSD values were obtained.After all, a HPLC method was developed for the determination of BUP in pharmaceuticals and in human plasma for the determination of BUP and HBUP, the major metabolite of BUP. The method was fully validated as shown in TLC method and the LOD and LOQ values of HPLC method were 9.09x10-8 M and 2.76x10-7 M for BUP and also, these parameters were determined as 4.68x10-7 M and 1.42x10-6 M respectively, for HBUP.As a result, the developed potentiometric, conductometric and spectrophotometric methods were found to be simple, fast, reliable and cost efficient. These methods were classical methods which can be used in all laboratories. The TLC and HPLC methods were both selective and sensitive. Developed methods were fully validated and the applicability of the methods for the determination of BUP in pharmaceuticals was demonsrated and the drug content was found to be in the limits of USP 29 suggestions. Also the applicability of the TLC and HPLC methods in human plasma were demonsrated and high recoveries were obtained with the low % RSD values.Key Words: bupropion hydrochloride, spectrophotometry, TLC, HPLC, tablet analysis, plasma analysis