ABSTRACT
In our present investigation, synthesis of nontoxic, eco friendly and cost effective silver nanoparticles, Phyllanthus acidus (P. acidus) was used as starting material. The influence of phyto-constituents present in aqueous extracts of Phyllanthus acidus was found to be effective in reduction of silver nitrate to free silver nanoparticles (PA-AgNPs). HPTLC finger print analysis reveals the presence of flavonoid, quercetin in aqueous extracts of Phyllanthus acidus. Surface plasmon racemonance exhibited λ max at 462 nm through UV-Vis spectroscopy. Zeta size revealed that the size of nanoparticles were with in the range of 65-250 nm with polydisperse index (PDI) of 0.451. The negative charge of zeta potential value (- 16.4) indicates repulsion among PA-AgNPs with their excellent stability. FESEM-EDAX, XRD and TEM analysis confirmed the presence of nano-crystalline PA-AgNPs with different morphological textures. Further, PA-AgNPs has shown potent antibacterial effect on E. coli cells. The greater antibacterial effect (viable and dead cells) of PA-AgNPs were confirmed by using acridine orange (AO) dye which can able to provide insight of healthy as well as damaged DNA. Live cells emit florescence green and dead cells (treated with PA-AgNPS at 20 and 40 µg/ml) appear as pale orange red colour. Post treatment, investigations of PA-AgNPs on E. coli cells under SEM was found to be effective against cell membrane damages which leads to cell death or cell growth arrest. Hence, from the above findings, we strongly recommend silver nanoparticles from Phyllanthus acidus can be used as a potential source for antimicrobial agent for chronic infections and also against other harmful microorganisms.
ABSTRACT
Microbial biofilms are microcosm attaching irreversibly to abiotic or biotic surfaces and they are promulgated as congregate of single or multiple populations. The potential of lipid- and polymer-based drug delivery carriers for eradicating biofilm consortia on device-related nosocomial infections is explored in this review. Liposomes-loaded with antimicrobial agents could effectively be applied as anti-biofilm coating to reduce microbial adhesion/colonisation onto medical devices and as drug delivery carriers to biofilm interfaces and in intracellular infection. Many polymer-based carrier systems have also been proposed, including those based on biodegradable polymers such as poly(lactide co-glycolide) as well as fibrous scaffolds and thermoreversible hydrogels and surface (properties) modified polymeric catheter materials such as antimicrobial, antiseptic or metallic substances-coated polymeric materials. Their contribution to the prevention/resolution of infection is reviewed.
