Development of mucus-penetrating iodine loaded self-emulsifying system for local vaginal delivery.

The major goal of this project was to formulate iodine-based self nano-emulsifying drug delivery system to provide improve antimicrobial activity and enhanced mucosal residence time via mucus penetration. Iodine SNEDDS (Self nano-emulsifying drug delivery system) with different concentration were formulated using castor oil as the oil phase, cremophor ethoxylated (CrEL) as a surfactant and after screening a number of vehicles, PEG 400 was employed as co-surfactant. Self-emulsification time, thermodynamic stability tests, robustness to dilution, percent transmittance, droplet size, and drug release were measured. Ternary phase diagrams were plotted to determine the area of emulsification. When compared to the commercial formulation, dissolving experiments revealed that the iodine from the SNEDDS enhanced aqueous solubility. In-vitro iodine release was determined to be around 15% per hour, with muco-adhesive and, muco-penetrating characteristics showing a 38-fold improvement. Furthermore, SNEDDS demonstrated significant antibacterial efficacy against Escherichia coli and Staphylococcus aureus. Similarly, when compared to marketed drugs, in-vitro drug absorption profile from the manufactured SNEDDS shown to be much higher. According to these results iodine containing SNEDDS could be a useful new formulation for iodine mucosal usage.

Thiolated Chitosan Microneedle Patch of Levosulpiride from Fabrication, Characterization to Bioavailability Enhancement Approach.

In this study, a first attempt has been made to deliver levosulpiride transdermally through a thiolated chitosan microneedle patch (TC-MNP). Levosulpiride is slowly and weakly absorbed from the gastrointestinal tract with an oral bioavailability of less than 25% and short half-life of about 6 h. In order to enhance its bioavailability, levosulpiride-loaded thiolated chitosan microneedle patches (LS-TC-MNPs) were fabricated. Firstly, thiolated chitosan was synthesized and characterized by nuclear magnetic resonance (1HNMR) spectroscopy, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, differential scanning calorimetry (DSC), and X-ray diffraction (XRD). Thiolated chitosan has been used in different drug delivery systems; herein, thiolated chitosan has been used for the transdermal delivery of LS. LS-TC-MNPs were fabricated from different concentrations of thiolated chitosan solution. Furthermore, the levosulpiride-loaded thiolated chitosan microneedle patch (LS-TC-MNP) was characterized by FTIR spectroscopic analysis, scanning electron microscopy (SEM) study, penetration ability, tensile strength, moisture content, patch thickness, and elongation test. LS-TC-MNP fabricated with 3% thiolated chitosan solution was found to have the best tensile strength, moisture content, patch thickness, elongation, drug-loading efficiency, and drug content. Thiolated chitosan is biodegradable, nontoxic and has good absorption and swelling in the skin. LS-TC-MNP-3 consists of 100 needles in 10 rows each with 10 needles. The length of each microneedle was 575 µm; they were pyramidal in shape, with sharp pointed ends and a base diameter of 200 µm. The microneedle patch (LS-TC-MNP-3) resulted in-vitro drug release of 65% up to 48 h, ex vivo permeation of 63.6%, with good skin biocompatibility and enhanced in-vivo pharmacokinetics (AUC = 986 µg/mL·h, Cmax = 24.5 µg/mL) as compared to oral LS dispersion (AUC = 3.2 µg/mL·h, Cmax = 0.5 µg/mL). Based on the above results, LS-TC-MNP-3 seems to be a promising strategy for enhancing the bioavailability of levosulpiride.