The use of electrospinning technology in enzymes preservation and chemical warfare protective clothing applications

The effect of electrospinning on the catalytic activity of various enzymes was investigated. Three enzymes were used as models: Trypsin, RNase, and LDH; the residual activities of these enzymes after spinning were 73%, 71%, and 20%, respectively. The reduction in catalytic activity was attributed to the stresses associated with the technique, especially in the case of LDH where the enzyme may be dissociated to its subunits. In some cases the residual activities were improved when additives were used. The effect of electrospinning parameters (polymer solution viscosity, duration of spinning, strength of electric field, and gap distance) on enzyme activity was investigated, and it was found that some of these parameters need to be optimized in order to obtain the best-retained activity. The pH-activity profile and other kinetic studies were conducted. The optimum pH values for the native and PEOz-spun trypsin were the same at pH7.5. Also, it was found that while PEOz was a good stabilizer, it was an inhibitor for the trypsin-BAEE reaction.; The electrospinning technique was applied to produce fibrous mats that can be used as a protective material against chemical warfare agents. PVA and PEOz fibers were produced and their catalytic activities in hydrolyzing PNEPP were examined. PVA fibers were cross-linked and coordinated with Cu(II) to form a Cu-polymer complex; it was found that PVA-Cu fibrous mats had a low ability to hydrolyze PNEPP. To make PVA fibers more effective, OPAA was incorporated into PVA fibers. Also, OPAA was spun with PEOz fibers, and PEOz fibers were sandwiched between two layers of insoluble fibrous mats of PCL and polyurethanes. The resultant multilayered fibrous mats were effective in hydrolyzing PNEPP; however, their efficiencies were varied.