Green Chemistry Approach for the Synthesis of Gold Nanoparticles Using the Fungus Alternaria sp.
The synthesis of gold nanoparticles has gained tremendous attention owing to their immense applications in the field of biomedical sciences. Although several chemical procedures are used for the synthesis of nanoparticles, the release of toxic and hazardous by-products restricts their use in biomedical applications. In the present investigation, gold nanoparticles were synthesized biologically using the culture filtrate of the filamentous fungus Alternaria sp. The culture filtrate of the fungus was exposed to three different concentrations of chloroaurate ions. In all cases, the gold ions were reduced to Au(0), leading to the formation of stable gold nanoparticles of variable sizes and shapes. UV-Vis spectroscopy analysis confirmed the formation of nanoparticles by reduction of Au(3+) to Au(0). TEM analysis revealed the presence of spherical, rod, square, pentagonal, and hexagonal morphologies for 1 mM chloroaurate solution. However, quasi-spherical and spherical nanoparticles/heart-like morphologies with size range of about 7-13 and 15-18 nm were observed for lower molar concentrations of 0.3 and 0.5 mM gold chloride solution, respectively. The XRD spectrum revealed the face-centered cubic crystals of synthesized gold nanoparticles. FT-IR spectroscopy analysis confirmed the presence of aromatic primary amines, and the additional SPR bands at 290 and 230 nm further suggested that the presence of amino acids such as tryptophan/tyrosine or phenylalanine acts as the capping agent on the synthesized mycogenic gold nanoparticles.
Department of Biotechnology, School of Life Sciences, Pondicherry University, Kalapet, Puducherry 605 014, India.
Naresh Niranjan
NN
Dhanasekar
Department of Biotechnology, School of Life Sciences, Pondicherry University, Kalapet, Puducherry 605 014, India.
Ganga Ravindran
GR
Rahul
Department of Biotechnology, School of Life Sciences, Pondicherry University, Kalapet, Puducherry 605 014, India.
Kannan Badri
KB
Narayanan
Department of Biotechnology, School of Life Sciences, Pondicherry University, Kalapet, Puducherry 605 014, India.
Gurusamy
G
Raman
Department of Biotechnology, School of Life Sciences, Pondicherry University, Kalapet, Puducherry 605 014, India.
Natarajan
N
Sakthivel
D000528:Alternaria / Q000378:metabolism*; D002712:Chlorides / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry; D006046:Gold / Q000378:metabolism*; D017612:Gold Compounds / Q000378:metabolism; D055772:Green Chemistry Technology / Q000379:methods*; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000378:metabolism* / Q000648:ultrastructure; D010084:Oxidation-Reduction; D013053:Spectrophotometry
D002712:Chlorides; D003470:Culture Media; D017612:Gold Compounds; D006046:Gold; C024568:gold tetrachloride, acid
Alternaria sp.; electron microscopy; filamentous fungus; gold nanoparticles; surface plasmon resonance