Saboo, Sugandha published the artcileCongruent release of drug and polymer: A “”sweet spot”” in the dissolution of amorphous solid dispersions, Synthetic Route of 21829-25-4, the main research area is amorphous solid dispersion liquid phase separation drug congruent release; Amorphous solid dispersion; Congruent release; Dissolution; Liquid-liquid phase separation.
Liquid-liquid phase separation (LLPS) occurs following amorphous solid dispersion (ASD) dissolution when the drug concentration exceeds the “”amorphous solubility””, and is emerging as an important characteristic of formulations that may enhance the oral bioavailability of poorly soluble drugs. The purpose of this research was to identify criteria that impact the rate and extent of drug release and hence the occurrence or not of LLPS upon ASD dissolution The model polymer was poly (vinylpyrrolidone-co-vinyl acetate) (PVPVA). Nil-PVPVA and Cil-PVPVA ASDs with different drug loadings were prepared Surface area normalized dissolution rates of both the drug and the polymer from ASD tablets were studied. At a similar and relatively low drug loading (<20% weight/weight drug), dissolution of both Nil-PVPVA and Cil-PVPVA ASDs was found to switch from rapid, congruent (i.e., simultaneous) release of drug and polymer to incongruent release with slow release of drug. SEM (SEM) and micro-computed tomog. (micro-CT) showed the presence of characteristic ""pits"" on the surface of partially dissolved, incongruently releasing ASD tablets. This study demonstrates two important findings, firstly, a link between congruent release of drug and polymer and the occurrence of LLPS and secondly, the switch between congruent and incongruent release of drug and polymer is a result of competitive kinetics between phase separation and the release rate of ASD components with minimal influence from drug hydrophobicity for two structural analogs. Journal of Controlled Release published new progress about Crystals. 21829-25-4 belongs to class pyridine-derivatives, name is Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C17H18N2O6, Synthetic Route of 21829-25-4.