Improvement in the dissolution profile of diacerein using a surfactant-based solid dispersion technique

In an attempt to improve the dissolution rate of poorly aqueous soluble diacerein (DCN), solid dispersions (SDs) were prepared with a surfactant Pluronic® F 127 (PXMR) at drug to polymer ratios of 1:0.5, 1:1.5, and 1:2.5 (w/w) by an ordinary melting technique. The interaction of DCN with PXMR in all solid binary systems was evaluated by thin layer chromatography (TLC), Fourier transform infrared spectrometry (FTIR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) studies. TLC indicated an absence of chemical interaction of DCN with PXMR whereas FTIR studies demonstrated an existence of strong hydrogen bonding between them. A uniform molecular dispersion of DCN was observed in DSC thermograms, and this finding was further supported by loss of the crystalline and irregular shape of DCN detected in SEM photomicrographs. Dissolution studies were promptly conducted to examine the release rate performance of DCN from all binary systems. The drug dissolution properties of binary systems improved significantly in comparison to crystalline DCN. The rate and extent of DCN release were observed to be strongly dependent on the proportion of PXMR present within the formulations.