In vitro studies of a degradable device for controlled-release of meloxicam

WOS: 000229956300014PubMed ID: 15966885Background: Plaque biofilm and associated host responses are the primary factors in the pathogenesis of periodontitis. Delivery of medications directly into the periodontal pockets to suppress or eradicate the pathogenic microbiota or modulate the inflammatory response has attracted significant interest to limit periodontal tissue destruction. The aim of the present study was twofold: (1) to describe the development of a biodegradable controlled-release device containing meloxicam as the therapeutic agent and (2) to evaluate the in vitro release of meloxicam from this device into different release media. Methods: Films of cross-linked gelatin matrix containing meloxicam were prepared, hardened for various time periods and cut in a form to fit to the periodontal pocket anatomy. The release of active agents was studied separately in 10 ml distilled water, artificial saliva and pH 7.4 phosphate buffer at 37 degrees C. Apparatus Vibrax was used at 120 r.p.m. Determinations were carried out spectrophotometrically, and the release profiles were plotted as a function of time. The results were evaluated by the similarity test. Results: The release rates of meloxicam from the hardened (1h, 4h, 8 h) formulations were slower than the unhardened formulation in all the three release media. Increasing the hardening time decreased the release rates. The overall release rates were similar in artificial saliva and pH 7.4 phosphate buffer, while it was lower in distilled water. Conclusions: As a conclusion, cross-linked gelatin matrix films may be considered as a suitable inert material for obtaining a prolonged local release of meloxicam as an adjunct to the mechanical periodontal treatment. As required, further in vitro and in vivo studies will be performed before starting clinical applications of this controlled-release formulation of the anti-inflammatory agent

Reducing the energy demand of cellulosic ethanol through salt extractive distillation enabled by electrodialysis

One of the main challenges when a biochemical conversion technique is employed to produce cellulosic ethanol is the low concentration of ethanol in the fermentation broth, which increases the energy demand for recovering and purifying ethanol to fuel grade. In this study, two design cases implementing salt extractive distillation – with salt recovery enabled by a novel scheme of electrodialysis and spray drying – along with heat integrated distillation techniques of double-effect distillation and direct vapor recompression are investigated through process simulation with Aspen Plus® 2006.5 for reducing the thermal energy demand. Conventional distillation along with molecular sieve based dehydration is considered as the base case. Salt extractive distillation along with direct vapor recompression is found to be the most economical ethanol recovery approach for cellulosic ethanol with a thermal energy demand of 7.1 MJ/L (natural gas energy equivalents, higher heating value), which corresponds to a thermal energy savings of 23% and cost savings of 12% relative to the base case separation train thermal energy demand and total annual cost