Novel fast dissolving freeze dried sublingual baicalin tablets for enhanced hepatoprotective effect: in-vitro characterization, cell viability, and in-vivo evaluation

Baicalin (BG), a natural product, has been used in the prevention and treatment of drug-induced liver injury (DILI); however, its poor solubility and extensive liver metabolism limit its pharmacological use. The aim of the present study was the formulation of fast-dissolving freeze-dried sublingual tablets (FFSTs) to increase BG dissolution, avoid first-pass metabolism, and overcome swallowing difficulties. FFSTs were prepared following a 23 factorial design. The effect of three independent variables namely matrix former, Maltodextrin, concentration (4%, and 6%), binder concentration (2%, and 3%), and binder type (Methocel E5, and Methocel E15) on the FFSTs' in-vitro disintegration time and percentage dissolution was studied along with other tablet characteristics. Differential scanning calorimetry, scanning electron microscopy, in-vitro HepG2 cell viability assay, and in-vivo characterization were also performed. F8 (6% Maltodextrin, 2% Mannitol, 2% Methocel E5), with desirability of 0.852, has been furtherly enhanced using 1%PEG (F10). F10 has achieved an in-vitro disintegration time of 41 secs, and 60.83% in-vitro dissolution after 2 min. Cell viability assay, in-vivo study in rats, and histopathological studies confirmed that pretreatment with F10 has achieved a significant hepatoprotective effect against acetaminophen-induced hepatotoxicity. The outcome of this study demonstrated that FFSTs may present a patient-friendly dosage form against DILI.