Simultaneous quantification of drug and coformer during cocrystal dissolution using

Background and purpose: The primary objective of this study was to assess the feasibility of applying Experimental approach: The rotating-vessel μDISS system equipped with an Key results: The concentrations of CBZ and the coformer were successfully quantified by MCA throughout the dissolution process. In the absence of a polymeric precipitation inhibitor (PPI), the dissolution of CBZ from the cocrystal reached only 20%, and no supersaturation was observed, whereas the coformers were rapidly released. In contrast, in the presence of PPIs, the dissolution of CBZ from the cocrystal increased to supersaturated levels, while the dissolution of the coformer decreased. Supersaturation of CBZ was achieved when CBZ and the coformer dissolved congruently. A PPI may interfere with the molecular dissociation of CBZ and the coformer from the cocrystal surface, resulting in a slower release of both CBZ and the coformer. This effect may have reduced the local CBZ concentration at the particle surface and, consequently, slowed the precipitation of CBZ dihydrate on the particle surface. Conclusion: MCA enables the simultaneous quantification of a drug and its coformer from