TY - JOUR
T1 - Light mediated generation of silver nanoparticles by spinach thylakoids/ chloroplasts
AU - Shabnam, Nisha
AU - Sharmila, P.
AU - Kim, Hyunook
AU - Pardha-Saradhi, P.
N1 - Publisher Copyright:
© 2016 Shabnam et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
PY - 2016/12
Y1 - 2016/12
N2 - The unique potential of chloroplasts/thylakoids to harness light energy to transport electrons from H2 O 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 crystalline NPs composed of Ag. Powder X-ray diffraction (PXRD) analysis revealed that Ag-NPs were biphasic composed of face-centered cubic Ag0 and cubic Ag2 O. X-ray photoelectron spectroscopy (XPS) data further corroborated the presence of Ag2 O in Ag-NPs. Limited formation of Ag-NPs in dark and increased generation of Ag0 /Ag2 O-NPs with increase in light intensity (photon flux density) by thylakoids/chloroplasts, established the role of light-harvesting photosynthetic machinery in generation of Ag0 /Ag2 O-NPs. Potential of thylakoids/chloroplasts to generate Ag-NPs from Ag+ on exposure to red and blue wavelength regions of visible light of electromagnetic spectrum, further confirmed the involvement of photosynthetic electron transport in reduction of Ag+ and generation of Ag-NPs. While light energy mediated photosynthetic electron transport donates energized electrons extracted from H2 O to Ag+ to form Ag0 -NPs, O2 released as a by-product during photolysis of H2 O oxidizes Ag0 to form Ag2 O-NPs. Our findings furnish a novel, simple, economic and green method that can be exploited for commercial production of Ag0 /Ag2 O-NPs.
AB - The unique potential of chloroplasts/thylakoids to harness light energy to transport electrons from H2 O 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 crystalline NPs composed of Ag. Powder X-ray diffraction (PXRD) analysis revealed that Ag-NPs were biphasic composed of face-centered cubic Ag0 and cubic Ag2 O. X-ray photoelectron spectroscopy (XPS) data further corroborated the presence of Ag2 O in Ag-NPs. Limited formation of Ag-NPs in dark and increased generation of Ag0 /Ag2 O-NPs with increase in light intensity (photon flux density) by thylakoids/chloroplasts, established the role of light-harvesting photosynthetic machinery in generation of Ag0 /Ag2 O-NPs. Potential of thylakoids/chloroplasts to generate Ag-NPs from Ag+ on exposure to red and blue wavelength regions of visible light of electromagnetic spectrum, further confirmed the involvement of photosynthetic electron transport in reduction of Ag+ and generation of Ag-NPs. While light energy mediated photosynthetic electron transport donates energized electrons extracted from H2 O to Ag+ to form Ag0 -NPs, O2 released as a by-product during photolysis of H2 O oxidizes Ag0 to form Ag2 O-NPs. Our findings furnish a novel, simple, economic and green method that can be exploited for commercial production of Ag0 /Ag2 O-NPs.
UR - http://www.scopus.com/inward/record.url?scp=85004064325&partnerID=8YFLogxK
U2 - 10.1371/journal.pone.0167937
DO - 10.1371/journal.pone.0167937
M3 - Article
C2 - 27936248
AN - SCOPUS:85004064325
SN - 1932-6203
VL - 11
JO - PLoS ONE
JF - PLoS ONE
IS - 12
M1 - e0167937
ER -