Zaleplon

Rapid oral transmucosal delivery of zaleplon-lavender oil utilizing self-nanoemulsifying lyophilized tablets technology: development, optimization and pharmacokinetic evaluation

Based on the administration convenience, transmucosal buccal drug delivery allows special strength points over peroral routes for systemic delivery. It could achieve local or systemic effect and boost drugs’ bioavailability for agents with first pass metabolism. The current study aimed to manufacture and optimize a lavender oil–based nanoemulsion loaded with zaleplon and incorporate it into fast-disintegrating tablets to promote its dissolution and oral bioavailability via oral mucosa. Zaleplon-loaded nanoemulsions were devised with various levels of lavender oil (10% to 25%), the surfactant Sorbeth-20 (35% to 65%), and the co-surfactant HCO-60 (20% to 40%); the extreme vertices mixture statistical design was adopted. The droplet size and drug-loading efficiency were the evaluated. The optimal formulation was transformed into self-nanoemulsified lyophilized tablets (ZP-LV-SNELTs), which were tested for their uniformity of content, friability, and disintegration time with in-vitro release. Finally, the pharmacokinetic parameters of the ZP-LV-SNELTs were determined and compared with those of marketed formulations. The optimal nanoemulsion had a droplet size of 87 nm and drug-loading capacity of 185 mg/mL. ZP-LV-SNELTs exhibited acceptable friability and weight uniformity and a short disintegration time. The in-vitro release of ZP-LV-SNELTs was 17 times faster than that of the marketed tablet. Moreover, the optimal ZP-LV-SNELTs increased the bioavailability of zaleplon in rabbits by 1.6-fold compared with the commercial tablets. Hence, this investigation revealed that ZP-LV-SNELTs delivered zaleplon with enhanced solubility, a fast release, and boosted bioavailability thru oral mucosa which provided a favorable route for drug administration which is suggested to be clinically investigated in future studies

Solvent effects on the absorption and fluorescence spectra of Zaleplon: Determination of ground and excited state dipole moments

Solvent effects on the absorption and fluorescence spectra of Zaleplon, a nonbenzodiazepine sedative/hypnotic drug that is mainly used for the short term treatment of insomnia, were investigated in 18 different solvents with diverse polarities. Dipole moments of the ground and excited state (μ_g and μ_e) were determined by Lippert-Mataga, Bakhshiev, Reichardt, McRae and Suppan solvatochromic methods. The dipole moment of Zaleplon ground state in the gas phase has been calculated as μ_g = 10.95 D (TD-DFT) with B3LYP/cc-pVTZ functional. There is a good agreement of theoretical data with Reichardt, McRae, and Suppan correlations, while some dissidence with Lippert-Mataga and Bakhshiev equations is suggesting the occurrence of specific solute-solvent interactions. Additionally, multiple linear regression analysis with Kamlet-Taft and Catalan solvatochromic models was applied to solute-solvent interactions. Dominant property of the solvent that affects the absorption band and Stokes shifts of Zaleplon is polarity of the solvent while the emission band is influenced mainly by solvent basicity.