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Ferrous fumarate, [C4H2FeO4] is widely utilized in the effective treatments and prevention of iron deficiency anemia. But, its administration has been oftentimes linked with quite a few side effects than ferric products. To overcome the side effects, multiple water-in-oil-in-water (W/O/W) emulsion formulations had been proposed as a new drug delivery system for the controlled release of entrapped active iron compound. In this study, high-pressure liquid whistle hydrodynamic cavitation reactor has been developed to produce highly stable W/O/W multiple emulsions containing Ferrous Fumarate in submicron scale (∼600 nm) with the droplet-size distribution polydispersity index in the narrow regime (0.35–0.40). The microscopic observations confirmed that that the physical stability of the W/O/W emulsions was increased significantly with operating pressure and number of emulsification passes. Looking at the potential for scale-up, this could be a promising technique to produce multiple emulsions incorporated with active constituents. © 2012 American Institute of Chemical Engineers AIChE J, 59: 155–167, 2013

The main goal of the present work was to develop a novel aspirin containing water-in-oil-in-water (W/O/W)-type submicron multiple emulsions via two-stage ultrasound cavitational emulsification using Span 80 and Cremophor EL as lipophilic and hydrophilic emulsifiers for the formation of primary and secondary emulsions, respectively. Effect of the following parameters, i.e. concentration of emulsifiers, ultrasonic amplitude and second sonication period on the mean droplet diameter, polydispersity index, droplet size stability and drug entrapment efficiency was studied. The osmotic behavior of the ultrasonically prepared multiple emulsions was also studied with different glucose concentrations in the inner and outer aqueous phases. The presence of gelatin played an important role in preventing interdroplet coalescence via formation of interfacial rigid film. Core shell type of multiple droplets with mean droplet diameter of around 400 nm was produced using 1.25% w/w Span 80 and 0.5% w/w Cremophor EL. The experimental results have shown that the long-term stability of the W/O/W multiple emulsions is significantly improved with the addition of both 0.5% w/w of glucose and 1% w/w of gelatin in the inner phase. This investigation has clearly proved that the use of ultrasound cavitation is an efficient yet promising approach in the generation of stable and uniform submicron multiple emulsions of aspirin. Copyright © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.

Acoustic and hydrodynamic cavitation can be used for a variety of applications ranging from biological applications such as cell disruption to chemical reactions such as oxidation of organic pollutants in aqueous effluents, including biorefractory toxic chemicals. Different equipment used for cavitational effects was compared based on a model reaction (decomposition of potassium iodide resulting into iodine liberation). A correlation was developed for the prediction of the cavitational yield in terms of the cavity collapse pressure. This correlation, when used with earlier correlations for the pressure amplitude generated during the violent collapse of cavities, will help design engineers to choose particular equipment, operating conditions, and geometric parameters to achieve a desired chemical change. The developed equation relating the macroscopic reaction rates with the collapse pressure is the first of its kind reported in the literature. Pilot-plant-scale hydrodynamic cavitation orifice plate setup is most energy-efficient, with significantly higher cavitational yields for the model reaction.

Palladium catalyzed coupling of sulfinamide (II) with aryl halides gives sulfinated anilines which can be deprotected with HCl.

Coupling of aryl iodides bearing various functionalities including sensitive ones with alcohol (II) and subsequent silane cleavage allows the synthesis of substituted phenols under mild conditions.

Carbamic acid 2-trimethylsilylethyl ester (Teoc-NH 2 ) serves as an ammonia equivalent in the palladium-catalyzed amination of aryl bromides and aryl chlorides. Anilines with sensitive functional groups can be readily prepared using these amine derivatives.

Enhancement of the reaction rate by combining the beneficial effects of PTC and ultrasound has been explored in the present study by taking the transformation of benzamide by dehydration to give benzonitrile as a model system. It was found that there is a substantial reduction in the reaction time when ultrasound was coupled with PTC.

2-(Trimethylsilyl)ethanesulfonyl amide (SES-NH2) is an ammonia equivalent for the palladium-catalyzed amination of aryl bromides and aryl chlorides. Using these amine derivatives, it has been observed that anilines and anilines with sensitive functional groups can be readily prepared.