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The aims of this study are to increase and explain the mechanism of dissolution enhancement of isradipine using the sonoprecipitation method for stable nanosuspensions. There have been still few of published researches on formulation of isradipine using nanoparticle engineering. Nanosuspension systems were prepared upon various factors including amplitude and the time length of ultrasonication. The dissolution test was performed according to the USP paddle method in intestinal fluid (pH 6.8). The crystalline structure of drug, the molecular interaction, morphology and size of nanosuspension were also investigated to determine the mechanism of dissolution enhancement. The sonoprecipitation method with use of HPMC 6 showed its potential in enhancement of the drug release rate. Stable nanosuspension was significantly depended on amplitude and time of ultrasonication since these factors affected on the size of nanoparticles. The synergistic effects of reduction of drug crystallinity and particle size could increase the dissolution rate of isradipine by providing a stable nanosuspension. This work may contribute to a new strategy for improvement dissolution rate of isradipine.

Along with the search for new therapeutic agents, advanced formulation and fabrication of drug carriers are required for better targeting, sensing, and responding to environmental stimuli as well as maximizing treatment efficiency. The emergence of intelligent therapeutics involves the use of functional biomaterials to mimic biological system for prolonged circulation and to work harmoniously with the body. One of the main concerns lies in the feasibility of creating systems with well-defined architectures including size, shape, components, and functionality. This review provides an overview regarding current challenges and potential of manufacturing and fabrication of biomaterials at small scales for various biomedical applications. Accordingly, novel lithography-based fabrication approaches are introduced together with their remarkable applications. Besides being popular in microelectronics, lithography techniques have demonstrated a great potential use for drug delivery, tissue engineering, and diagnostic tools.

A high amylase producing Bacillus subtilis WD 161 was used in a co-culture with Clostridium butylicum TISTR 1032 to enhance acetone–butanol–ethanol (ABE) production from starch. The mixed culture of C. butylicum TISTR 1032 and B. subtilis WD 161 without anaerobic pretreatment by reducing agent and N 2 flushing increased amylase activity 10 folds and enhanced ABE production 5.4 and 6.5 folds from soluble starch and cassava starch, respectively, compared to those of the pure culture of Clostridium itself. The medium optimization for ABE production by the mixed culture without anaerobic pretreatment found that cassava starch concentration of 40 g/L, C/N ratio of 4.35 and the mixed nitrogen sources of 265 mM yeast extract and 100 mM NH 4 NO 3 gave the highest ABE production in terms of final concentration and productivity. The benefits of using this high amylase producing aerobic Bacillus in a co-culture with anaerobic Clostridium were not only increasing substrate utilization and ABE production but there was also no requirement to add any costly reducing agent to the medium or flushing with N 2 to ensure anaerobic condition. This thus makes the anaerobic fermentation more economical and cost effective. This co-culture system may contribute greatly to developing industrialized ABE production.