Influence of Short Uptake Moisture on Drug-Excipient Binary Mixture: DSC and FTIR Contribution

This study aimed to evaluate a physicochemical stability between Acebutolol hydrochloride (ACB) and different common excipients: Polyvinylpyrrolidone (PVP), Magnesium Stearate (MgSt), Ascorbic acid (ASC), Citric acid (CIT), Butylhydroxyanisol (BHA) after exposure to short time under water vapor. This compatibility study was performed using mainly Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared Spectroscopy in ATR mode (FTIR-ATR) for the binary physical mixtures of ACB-excipients in different ratio. Different thermal behaviours were illustrated for ACB in presence of various excipients in term of melting temperature (T-m). For excipients with lower T-m than ACB, an adversary effect was highlighted by DSC analysis; in the presence of all proportions of MgSt, the ACB stability was not affected, however in the presence of CIT and BHA, seriously ACB interaction was involved. The mixture of ACB with ASC involved an eutectic system leading to improvement of hygroscopic stability. However with PVP the system encountered a deliquescence. The result underlines that DSC was more relevant to FTIR analysis to highlight the incidence of slight uptake of moisture on acebutolol in presence of ASC and PVP.