Ketoprofen-loaded polymer carriers in bigel formulation: an approach to enhancing drug photostability in topical application forms

Abstract

The purpose of the study was to investigate the stability and biopharmaceutical characteristics of ketoprofen, loaded in polymeric carriers, which were included into a bigel in a semisolid dosage form. The polymer carriers with in situ-included ketoprofen were obtained by emulsifier-free emulsion polymerization of the monomers in aqueous medium or a solution of the polymers used. The morphological characteristics of the carriers, the in vitro release and the photochemical stability of ketoprofen were evaluated. The model with optimal characteristics was included in a bigel formulation. The bigel was characterized in terms of pH, rheological behavior, spreadability, and in vitro drug release. Acute skin toxicity, antinociceptive activity, anti-inflammatory activity, and antihyperalgesic effects of the prepared bigel with ketoprofen-loaded polymer carrier were evaluated. The carriers of ketoprofen were characterized by a high yield and drug loading. The particle size distribution varied widely according to the polymer used, and a sustained release was provided for up to 6 hours. The polymer mixture poly(vinyl acetate) and hydroxypropyl cellulose as a drug carrier, alone or included in the bigel composition, improved the photostability of the drug compared with unprotected ketoprofen. The bigel with ketoprofen-loaded particles provided sustained release of the drug and had optimal rheological parameters. In vivo experiments on the bigel showed no skin inflammation or irritation. Four hours after its application, a well-defined analgesic, anti-inflammatory, and antihyperalgesic effect was registered. The polymer mixture of poly(vinyl acetate) and hydroxypropyl cellulose as a carrier of ketoprofen and the bigel in which it was included provided an enhanced photostability and sustained drug release.

Enzyme Responsive Vaginal Microbicide Gels Containing Maraviroc and Tenofovir Microspheres Designed for Acid Phosphatase-Triggered Release for Pre-Exposure Prophylaxis of HIV-1: A Comparative Analysis of a Bigel and Thermosensitive Gel

“…Its viscosity value taken at room temperature was 8840 cps. Bigels are a blend of a highly a viscous organogel and less viscous hydrogel, which results in a gel with good spreadability and retention that should surmount the problems of messiness and leakage associated with previous conventional gels [ 23 ].…”

Improvement of Skin Penetration, Antipollutant Activity and Skin Hydration of 7,3′,4′-Trihydroxyisoflavone Cyclodextrin Inclusion Complex

“…Photostability assay was performed by the method of Andonova et al with some modifications [23]. Solutions of 5-7HP containing 1 mg 734THIF and 1 mL water were exposed to outdoor daylight for 0, 12, 24, 48, 72, 96, 120, 144, and 168 h. In addition, the powder form of 5-7HP containing 1 mg 734THIF was exposed for 0 and 168 h. After light exposure, the samples were filtered with 0.45 μm syringe filter and analyzed by HPLC.…”

Denatonium benzoate decreases the effect of histamine in vitro and in rats

“…One hour after the treatment, the animals received subplantar injection of 100 μL of a 0.1 % solution of histamine in saline into the right paw [15]. Before the injection of histamine and 5, 15, 30, 60, 90 and 120 min after the treatment the anti-inflammatory effect was studied using Plethysmometer (UgoBasile, Gemonio, Italy) as described previously [16].…”