Pharmaceutically active supported ionic liquids

Andreea Cojocaru, Amal Siriwardana, Cabriela Curau, and Robin D. Rogers 

Active Pharmaceutical Ingredients in Ionic Liquid Form 

Supported Ionic Liquids Fundamentals and Applications, First Edition. 

Edited by Rasmus Fehrmann, Anders Riisager, and Marco Haumann. 

The liquid property of the API-ILs seems to be one solution to overcome the disadvantages of limited solubility, low bioavailability, variable polymorphs, and limited membrane transport, but in the same time may also present challenges related to their preparation, handling, and the need for special devices for dehvery. Recently, we showed that a supported ionic Hquid phase (SILP) strategy [17] not only can be successfully applied to API-ILs, but also provides an easier way to handle and dose these liquid APIs with additional advantages such as improved thermal stability and rapid and complete leaching from the solid support 

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Catalytically active supported ionic liquid membranes were used for propylene/propane vapor mixture separation. In this case, the ionic Hquid was immobilized in the pores of an asymmetric ceramic support, displaying sufficient permeability, good selectivity, and long-term stabUity [51]. Porous inorganic membranes were also used as a support for chiral-selective liquid membranes. For this purpose, porous tubular ceramic membranes were impregnated with 3-cyclodextrin polymer. Such SLMs were used for separation of enantiomers of racemic pharmaceutical chlorthahdone [52]. 

A novel application for ionic hquids in the preparation of functional materials has also served as a pre-immobilization strategy for a robust laccase electrode. In this case, the enzyme was first adsorbed to an ioiuc liquid-functionalized cellulose acetate that was then incorporated into a carbon paste electrode. The approach served to produce a device with acceptable levels of accuracy for methyldopa determination in pharmaceutical samples. In a similar manner, microencapsulation of laccase from T. versicolor in polyethylenimine (PEI) was demonstrated as a prior treatment for creating a coating on a paper support. Although first attempts showed a deleterious effect of PEI on laccase because of negative conformafional changes that reduced the activity of the encapsulated enzyme [28], optimized microencapsulation conditions resulted in superior stabihty compared with free enzyme [27]. 

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