Design and Optimization of Silymarin Loaded in Lyophilized Fast Melt Tablets to Attenuate Lung Toxicity Induced Via HgCl2 in Rats

The present study aimed to develop fast melting tablets (FMTs) using silymarin (SM) owing to FMTs rapid disintegration and dissolution. FMTs represent a pathway to help patients to increase their compliance level of treatment via facile administration without water or chewing beside reduction cost. One of the methods for FMTs formulation is lyophilization. Optimization of SM-FMTs was developed via a 32 factorial design. All prepared SM-FMTs were evaluated for weight variation, thickness, breaking force, friability, content uniformity, disintegration time (DT), and % SM released. The optimized FMT formula was selected based on the criteria of scoring the fastest DT and highest % SM released after 10 min (Q10). Optimized FMT was subjected to Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), and scanning electron microscopy (SEM) besides investigating its lung-protective efficacy. All SM-FMT tablets showed acceptable properties within the pharmacopeial standards. Optimized FMT (F7) scored a DT of 12.5 ± 0.64 Sec and % SM released at Q10 of 82.69 ± 2.88%. No incompatibilities were found between SM and excipients, it showed a porous structure under SEM. The optimized formula decreased cytokines, up-regulated miRNA133a, and down-regulated miRNA-155 and COX-2 involved in the protection against lung toxicity prompted by HgCl2 in a manner comparable to free SM at the same dosage.