The purpose of this study was to develop a suitable mucoadhesive in situ gel formulation of clotrimazole (CLO) for the treatment of vaginal candidiasis. For this aim, the mixture of poloxamer (PLX) 407 and 188 were used to prepare in situ gels. Hydroxypropyl methylcellulose (HPMC) K100M or E50 was added to in situ gels in 0.5% ratio to improve the mucoadhesive and mechanical properties of formulations and to prolong the residence time in vaginal cavity. After the preparation of mucoadhesive in situ gels; gelation temperature/time, viscosity, mechanical, mucoadhesive, syringeability, spreadibility and rheological properties, in vitro release behavior, and anticandidal activities were determined. Moreover vaginal retention of mucoadhesive in situ gels was investigated with in vivo distribution studies in rats. Based on the obtained results, it was found that gels prepared with 20% PLX 407, 10% PLX 188 and 0.5% HPMC K100M/E50 might be suitable for vaginal administration of CLO. In addition, the results of in vivo distribution studies showed that gel formulations remained on the vaginal mucosa even 24 h after application. In conclusion, the mucoadhesive in situ gels of CLO would be alternative candidate for treatment of vaginal candidiasis since it has suitable gel properties with good vaginal retention.

This study developed and examined the characterization of Benzidamine hydrochloride (BNZ) bioadhesive gels as platforms for oral ulcer treatments. Bioadhesive gels were prepared with four different hydroxypropylmethylcellulose (HPMC) types (E5, E15, E50 and K100M) with different ratios. Each formulation was characterized in terms of drug release, rheological, mechanical properties and adhesion to a buccal bovine mucosa. Drug release was significantly decreased as the concentration and individual viscosity of each polymeric component increased due to improved viscosity of the gel formulations. The amount of drug released for the formulations ranged from 0.76 ± 0.07 and 1.14 ± 0.01 (mg/cm² ± SD). Formulations exhibited pseudoplastic flow and all formulations, increasing the concentration of HPMC content significantly raised storage modulus (G′), loss modulus (G″), dynamic viscosity (ŋ′) at 37°C. Increasing concentration of each polymeric component also significantly improved the hardness, compressibility, adhesiveness, cohesiveness and mucoadhesion but decreased the elasticity of the gel formulations. All formulations showed non-Fickian diffusion due to the relaxation and swelling of the polymers with water. In conclusion, the formulations studied showed a wide range of mechanical and drug diffusion characteristics. On the basis of the obtained data, the bioadhesive gel formulation which was prepared with 2.5% HPMC K 100M was determined as the most appropriate formulation for buccal application in means of possessing suitable mechanical properties, exhibiting high cohesion and bioadhesion.

Peer reviewed article authored by (Karavana SY, Gökçe EH, Rençber S, Özbal S, Pekçetin Ç, Güneri P, Ertan G). Read article or submit your manuscript for publishing.

Introduction: Bladder cancer is responsible for more than 130,000 deaths annually worldwide. Intravesical delivery of chemotherapeutic agents provides effective drug localization to the target area to reduce toxicity and increase efficacy. This study aimed to develop an intravesical delivery system of gemcitabine HCl (Gem-HCl) to provide a sustained-release profile, to prolong residence time, and to enhance its efficiency in the treatment of bladder cancer. Materials and methods: For this purpose, bioadhesive microspheres were successfully prepared with average particle size, encapsulation efficiency, and loading capacity of 98.4 μm, 82.657%±5.817%, and 12.501±0.881 mg, respectively. For intravesical administration, bioadhesive microspheres were dispersed in mucoadhesive chitosan or in situ poloxamer gels and characterized in terms of gelation temperature, viscosity, mechanical, syringeability, and bioadhesive and rheological properties. The cytotoxic effects of Gem-HCl solution, Gem-HCl microspheres, and Gem-HCl microsphere-loaded gel formulations were evaluated in two different bladder cancer cell lines: T24 (ATCC HTB4TM) and RT4 (ATCC HTB2TM). Results: According to cell-culture studies, Gem-HCl microsphere-loaded poloxamer gel was more cytotoxic than Gem-HCl microsphere-loaded chitosan gel. Antitumor efficacy of newly developed formulations were investigated by in vivo studies using bladder-tumor-induced rats. Conclusion: According to in vivo studies, Gem-HCl microsphere-loaded poloxamer gel was found to be an effective and promising alternative for current intravesical delivery-system therapies.

The aim of this study was to develop dexamethasone loaded nanoparticles for the local treatment of oral precancerous lesions. Dexamethasone loaded nanoparticles were prepared using the emulsification/solvent evaporation method. The prepared nanoparticles were characterised for pH, particle size, polydispersity index, zeta potential, morphology, encapsulation efficiency and drug loading. Furthermore, in vitro drug release, stability, ex vivo drug diffusion and cell culture studies were undertaken. The particle size, polydispersity index, zeta potential and encapsulation efficiency were found to be 200 nm, 0.2, -10 mV and 95%, respectively. Atomic Force Microscopy results showed that the formulated nanoparticles had uniform and spherical shape. In vitro release studies demonstrated 80% release of dexamethasone from nanoparticles; the nanoparticles were stable for 6 months. The ex vivo studies revealed no drug diffusion into the receptor media phase which suggests a possible local effect. Cytotoxicity studies showed that nanoparticles were non-cytotoxic against the HK-2 and NIH-3T3 cell lines. Findings of this study suggest that dexamethasone nanoparticles are promising and can be further investigated as potential treatment of oral precancerous lesions.