Ultrasonic Bioconversion Of Silver Ions Into Nanoparticles With Azadirachta Indica Extract And Coating Over Plasma-Functionalized Cotton Fabric

An ultrasonication approach was adopted for Azadirachta indica driven bioconversion of silver salt into silver nanoparticle (AgNPs). These nanoparticles were coated over plasma functionalized cotton by using a pad dry cure technique. For pre-coat surface functionalization, the cotton fabric was exposed to an open air single dielectric barrier discharge (DBD). The emission spectrum revealed that DBD consisted of NO, O-3, O, O2+ , O+, OH-, N-2 and N2+ species. The plasma treatment produced negative radicals on the surface and improved the adhesion of fabric for nanoparticles. The crystallographic analysis revealed cubical structure of nanoparticles with average size of 25 nm. The fabric got fully covered with AgNPs after five pad-dry cycles. Nanoparticles together with neem extract promoted the antimicrobial activity of the coated fabric. The inhibition zone of the silver coated fabric against E.Coli strains increased from 6 mm to 14 mm. The conductivity of fabric after 3, 5 and 7 cycles remained 2.56x 10(-2), 2.63x 10(-2) and 2.67x 10(-2) Siemens/cm, respectively. The coated fabric showed UV protection factor in the range of 210-269. The transmittance of UV-A radiations and UV-B radiations from the uncoated fabric was 19.27 % and 7.84 %, respectively, which reduced to 0.76 % and 0.24 % after 7 pad dry cycles.