Chitosan, known as sustainable materials with high metal binding activity and potential antibacterial properties is a promising natural polymer for high performance filtration. In case of “environmental concern”, creating an antibacterial material with a “green technology” and is an urgent. Through this research, low pressure plasma is used to synthesize silver nanopaticles in electrospinning chitosan nanofibers. Low pressure plasma offers way to reduce the usage of toxic chemical, time efficiency, and lower temperature processing in compare to other method such as chemical reduction, thermal, and UV- irradiation. This incorporation is expected to increase antibacterial properties of chitosan nanofibers.
Chitosan nanofibers had been successfully electrospun on pvc grid from 5.4% w/v of chitosan and 0.6% PEO. Fibers diameter was 136 nm ± 18% without bead structures. AgNO3 addition up to 2% did not significantly change chitosan nanofibers diameter.
Plasma treatment reduced Ag+ from AgNO3 precursor into Ag0 so that Ag nanoparticles were created. Besides, plasma also etched chitosan nanofibers so that reduction of fibers diameter is observed. UV- visible spectroscopy and XPS analysis revealed silver intensity will be increasing proportionally with plasma treatment time. XPS analysis also observed interaction between chitosan and Ag nanoparticles (N--Ag). Furthermore, TEM evaluation showed particle size average after 1.5 minutes plasma treatment was 1.5 nm in average. By addition of Ag nanoparticles, antibacterial activity of chitosan nanofibers could be enhanced.

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