Reducing Strength Prevailing at Root Surface of Plants Promotes Reduction of Ag+ and Generation of Ag0/Ag2O Nanoparticles Exogenously in Aqueous Phase
نویسندگان
چکیده
Potential of root system of plants from wide range of families to effectively reduce membrane impermeable ferricyanide to ferrocyanide and blue coloured 2,6-dichlorophenol indophenol (DCPIP) to colourless DCPIPH2 both under non-sterile and sterile conditions, revealed prevalence of immense reducing strength at root surface. As generation of silver nanoparticles (NPs) from Ag+ involves reduction, present investigations were carried to evaluate if reducing strength prevailing at surface of root system can be exploited for reduction of Ag+ and exogenous generation of silver-NPs. Root system of intact plants of 16 species from 11 diverse families of angiosperms turned clear colorless AgNO3 solutions, turbid brown. Absorption spectra of these turbid brown solutions showed silver-NPs specific surface plasmon resonance peak. Transmission electron microscope coupled with energy dispersive X-ray confirmed the presence of distinct NPs in the range of 5-50 nm containing Ag. Selected area electron diffraction and powder X-ray diffraction patterns of the silver NPs showed Bragg reflections, characteristic of crystalline face-centered cubic structure of Ag(0) and cubic structure of Ag2O. Root system of intact plants raised under sterile conditions also generated Ag(0)/Ag2O-NPs under strict sterile conditions in a manner similar to that recorded under non-sterile conditions. This revealed the inbuilt potential of root system to generate Ag(0)/Ag2O-NPs independent of any microorganism. Roots of intact plants reduced triphenyltetrazolium to triphenylformazon and impermeable ferricyanide to ferrocyanide, suggesting involvement of plasma membrane bound dehydrogenases in reduction of Ag+ and formation of Ag(0)/Ag2O-NPs. Root enzyme extract reduced triphenyltetrazolium to triphenylformazon and Ag+ to Ag(0) in presence of NADH, clearly establishing potential of dehydrogenases to reduce Ag+ to Ag(0), which generate Ag(0)/Ag2O-NPs. Findings presented in this manuscript put forth a novel, simple, economically viable and green protocol for synthesis of silver-NPs under ambient conditions in aqueous phase, using root system of intact plants.
منابع مشابه
Light Mediated Generation of Silver Nanoparticles by Spinach Thylakoids/Chloroplasts
The unique potential of chloroplasts/thylakoids to harness light energy to transport electrons from H2O to various entities was exploited for reduction of Ag+ to generate nanoparticles (NPs). Spinach thylakoids/chloroplasts turned AgNO3 solutions brown in light, but not in dark. Besides showing Ag-NPs specific surface plasmon resonance band, these brown solutions showed presence of 5-30 nm crys...
متن کاملComparative analysis of antibacterial activity of Silver nanoparticles synthesized using leaf extract of wheat varieties
In the present study, we have reported the biological synthesis of silver nanoparticles (AgNPs) using aqueous leaf extract prepared by hot percolation treatment of wheat varities (PBW343, Triticum durum and Aegilops tauschii )for the reduction of silver ions to silver nanoparticles. Bioreduction of Ag+ to Ag0 was observed when aqueous extract augmented with silver nitrate (AgNO3) was incubated ...
متن کاملComparative analysis of antibacterial activity of Silver nanoparticles synthesized using leaf extract of wheat varieties
In the present study, we have reported the biological synthesis of silver nanoparticles (AgNPs) using aqueous leaf extract prepared by hot percolation treatment of wheat varities (PBW343, Triticum durum and Aegilops tauschii )for the reduction of silver ions to silver nanoparticles. Bioreduction of Ag+ to Ag0 was observed when aqueous extract augmented with silver nitrate (AgNO3) was incubated ...
متن کاملBiosynthesis of Silver nanoparticles using root extract of the medicinal plant Justicia adhatoda: Characterization, electrochemical behavior and applications
A facile and green approach has been developed to synthesize silver nanoparticle (Ag-NPs). This was carried out by a biosynthetic route using Justicia Adhatoda root extract as reducing and stabilizing agent. The structure, composition, average particle size (~25 nm) and surface morphology of Ag-NPs were characterized by the X-ray diffraction, transmission electron microscope and atomic...
متن کاملBiosynthesis of Silver nanoparticles using root extract of the medicinal plant Justicia adhatoda: Characterization, electrochemical behavior and applications
A facile and green approach has been developed to synthesize silver nanoparticle (Ag-NPs). This was carried out by a biosynthetic route using Justicia Adhatoda root extract as reducing and stabilizing agent. The structure, composition, average particle size (~25 nm) and surface morphology of Ag-NPs were characterized by the X-ray diffraction, transmission electron microscope and atomic...
متن کامل