Enzyme stabilization in nanostructured materials for use in organophosphorus nerve agents detoxification and prophylaxis
Enzyme immobilization and encapsulation in various nanostructures has drawn great interest as it offers both increased stability and reusability with-out significant loss in activity. Although we are still at the beginning of ex-ploring the use of these materials for biocatalysis, by now several nanostruc-tures have been tested as hosts for enzyme immobilization. The beneficial application of enzyme stabilization in nanostructured materials for use in nerve agent detoxification and pre-treatment is reviewed and discussed in this article. Organophosphorus hydrolyzing enzymes (e.g. OPAA, OPH, Paraoxonase) are capable of detoxifying neurotoxic chemical warfare (CW) agents, i.e. G-type, V-type, and related organophosphorus (OP)-based indus-trial materials. The nanoencapsulation of OP-hydrolyzing enzymes with mesoporous materials or dendritic polymers can provide a very stable and convenient formulation for use in chemical agent detoxification. Nanoencap-sulated enzymes demonstrated to be able to retain its activity in the presence of a number of organic solvents, commercial disinfectants and anti-microbial agents and foams, making them suitable for personnel decontamination and individual protection applications. OP-hydrolyzing enzymes also show great promise as catalytic bioscavengers to be used as safe and effective medical countermeasures to OP intoxication. Novel enzyme-complexed nano-delivery systems, particularly polymeric nanocapsules and sterically stabilized lipo-somes, can be used to carry these metabolizing enzymes to the circulation. Thus, it is possible to avoid the physiological disposition and potential immu-nological reactions of respective enzymes. Nanostructured delivery systems consequently allow for increasing the enzymes efficacy by extending their cir-culatory life and in some cases also their specific activity.