Designing Ecofriendly Bionanocomposite Assembly with Improved Antimicrobial and Potent on-site Zika Virus Vector Larvicidal Activities with its Mode of Action

Abstract

Dialyzed natural polymer, fibroin, from Bombyx mori was used to synthesize biocompatible silver and gold nanoparticles in-situ in dispersion form. The films of pure fibroin (PF), fibroin-silver nanocomposite (FSNC) and fibroin-gold nanocomposite (FGNC) were fabricated by drop casting method. The characterization of the resultant dispersion and films was performed by visual color change, UV-Vis spectroscopy and atomic force microscopy. The dispersions of PF, FSNC and FGNC were tested for antibacterial activity against E. coli NCIM 2065, S. aureus NCIM 5021, K. pneumoniae NCIM 2957, P. aeruginosa ATCC 9027 and antifungal activity against A. fumigatus NCIM 902. FSNC dispersion exhibited an effective antimicrobial action against all the tested microbes as compared to FGNC dispersion. The mechanism of action for FSNC and FGNC against these microorganisms is proposed. Additionally, the larvicidal activity of the films was investigated against the larvae of Aedes aegypti. The films of FSNC exhibited 100% mortality while the films of FGNC revealed 86–98% mortality against all the larval instars and pupae of A. aegypti. The phytotoxicity study of the nanocomposite films was also carried out to confirm the reusability of water. This is first noble metal nanocomposite based report on larvicidal activity of zika virus vector.

Terrestrial snail-mucus mediated green synthesis of silver nanoparticles and in vitro investigations on their antimicrobial and anticancer activities

“…3 a); while the composite spectrum of AgNPs-SM sample (Fig. 3 b) reveals (i) contribution from snail mucus with absorption peak centered at 293 nm and (ii) relatively sharp absorption peak centered at 420 nm attributable to characteristic Surface Plasmon Resonance (SPR) phenomenon reported for spherical silver nanoparticles 13 . The noticeable contribution from snail mucus and presence of relatively sharp characteristic SPR peak in the spectrum evidently suggests key role of mucus as bio-stabilizing medium in controlling the spontaneous aggregation of Ag nanoparticles.…”

“…The whole mixture was stirred at 250 rpm for 45 min and exposed to sunlight to sharpen the color of the dispersion mixture from gray to brown within short time period of 2–5 min implying the formation of silver nanoparticles 61 . This distinctive change in colour can be attributed to size and shape dependent Surface Plasmon Resonance of Ag nanoparticles in solution when exposed to visible light 13 . After visually noticing such a change in the color of the dispersion mixture, the powder product formed was collected by centrifugation at 12,000 RPM for 10 min and washed several times with double distilled water until its pH becomes neutral.…”

“…In this context, it may be noted that the nanomaterial-based drug development approaches cannot exert evolutionary pressure on bacteria and hence can be beneficial in combating MDR if biocompatibility and cytotoxicity issues are addressed aptly 12 . Interestingly, in our previous study, it was observed that the biologically synthesized silver nanocomposites do not exhibit toxicity against non-target organisms 13 . Silver nanoparticles are also used in water filters to kill the pathogenic micro-organisms which cause water borne diseases such as diarrhea 14 , 15 .…”

Highly sensitive label-free bio-interfacial colorimetric sensor based on silk fibroin-gold nanocomposite for facile detection of chlorpyrifos pesticide

“…In our previous work, it has been illustrated that UV-visible spectrum of the silk fibroin solution containing gold nanoparticles exhibits a Surface Plasmon Resonance (SPR) peak in the vicinity of 520 nm, which is a characteristic peak for gold nanoparticles and, in turn, confirms formation of gold nanoparticles within the SF solution matrix 40 . The gold nanoparticles produced through biological process in our study exhibit ruby red color which appears due to excitation of localized surface plasmon vibration of the metal nanoparticles 40,41 . The SPR peak broadening towards higher wavelength side may be because of capping environment (proteins) and/or wide particle size distribution 42 .…”

An Updated Review on Silver Nanoparticles in Biomedicine

“…Nanosilver-based formulations proved efficient therapeutic effects against several pathologies caused by clinically-relevant viruses, such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) [ 211 , 212 ], human papilloma virus (HPV) [ 213 ], rotavirus [ 214 , 215 ] and other enteric viruses [ 216 , 217 , 218 ]. It is worth mentioning that new and effective platforms containing AgNPs were evaluated for their biocidal activity against viral vectors, generally mosquito-borne pathogens including Zika virus [ 219 , 220 ], Dengue virus [ 221 , 222 ], West Nile virus [ 223 , 224 ] and Chikungunya virus [ 225 , 226 ].…”