Microwave Assisted Degradation Studies of Pharmaceuticals

Abstract

Use of microwave instruments can shorten the drug research time frame significantly newline-C. O. Kappe newlineStress testing as an important segment in the process of getting a drug to the market and is intended to reveal the stability related issues. In stress testing, it is mentioned to perform the task (hydrolytic or thermolytic degradation) at elevated temperature as and when required. Elevation in temperature by means of microwave irradiation has picked up a lot of consideration owing to the in-core heating of the medium. But at the same time it is essential to monitor and optimize parameters of microwave irradiation otherwise there are chances of a false interpretation of the results. An attempt has been made here to compare degradation profile of drug obtained by conventional heating and microwave heating. newlineA hydrolytic degradation study of active pharmaceutical ingredients (APIs) was compared using conventional and microwave-assisted heating techniques. Where acid hydrolytic degradation profile of Alprazolam, Atomoxetine, Repaglinide, Furosemide, Olmesartan, and Hydrochlorothiazide; alkali hydrolytic degradation profile of Escitalopram, Paliperidone, Risperidone, Lurasidone, Olmesartan, and Hydrochlorothiazide; and neutral hydrolytic degradation profile of Hydrochlorothiazide were generated. Microwave conditions were optimized to achieve approximately similar percentage of degradation as obtained by conventional heating technique. Using both the methods, same number of degradation products were generated in each analysed drug. No alteration in the degradation profile was observed for any drug in microwave-assisted degradation study compared to conventional degradation study. However, with the help of microwave heating, reaction time scale is drastically reduced from hours to minutes due to enhanced reaction rate. newlineHydrolytic degradation of marketed Tablet formulations of Buspirone and Lamotrigine was also carried out using microwave radiation induced heating. There was no alteration in the degrad