Biogenic synthesis of multidimensional gold nanoparticles assisted by Streptomyces hygroscopicus and its electrochemical and antibacterial properties

Abstract

The fabrication of reliable, green chemistry processes for nanomaterial synthesis is an important aspect of nanotechnology. The biosynthesis of single-pot room-temperature reduction of aqueous chloroaurate ions by Streptomyces hygroscopicus cells has been reported to facilitate the development of an industrially viable greener methodology for the synthesis of technologically important gold nanoparticles (AuNPs). Multidimensional AuNPs are generated via the manipulation of key growth parameters, including solution pH and reaction time. The synthesized nanostructures are characterized by UV/Vis and energy dispersive X-ray analysis studies. Particle morphology is characterized by HRTEM, FE-SEM and BioAFM. Additionally, we have demonstrated the electrochemical and antibacterial properties of AuNPs via cyclic voltammetry analysis and a minimal inhibitory concentration assay. Owing to the drawbacks of chemical synthesis, a biological synthesis method has been developed to generate biocompatible, inexpensive and eco-friendly size-controlled nanoparticles.

Mosquito larvicidal activity of silver nanoparticles synthesised using actinobacterium, Streptomyces sp. M25 against Anopheles subpictus, Culex quinquefasciatus and Aedes aegypti

“…The AgNPs were mixed into 10 mL of deionized water. Then the biosynthesised AgNPs were freeze-dried, powdered and used for XRD analysis (Sadhasivam et al 2012). EDX measurements of the AgNPs were performed by SEM-EDX (Model Jeol JFSM 6390).…”

“…The sharp intense peaks of the spectrum clearly indicated that the particles are in the nanoregime and also crystalline in nature. The size of the crystallite AgNPs was calculated using Debye-Scherrer formula (Sadhasivam et al 2012). The calculated crystallite size of Ag particle is *11.5 nm.…”

“…Based on the experimental results the interaction among biomolecules and surface of AgNPs were very strong. The crystal growth prejudiced by the inhibition of Control-nil mortality, a mean value of five replicates, significant at P \ 0.05 level, LC50 lethal concentration that kills 50 % of the exposed larvae UCL upper confidence limit, LCL lower confidence limit, r2 regression co-efficient, v2 Chi square, df degrees of freedom silver atom accumulation on the bacterial surface (Sadhasivam et al 2012;Ahmad et al 2003).…”

“…Most of the techniques are still in the developmental stage and various problems are often experienced with the stability of the nanoparticles preparations (Vahabi et al 2011). One of the major developments in nanotechnology is the synthesis of nanoparticles using living organisms such as plants, microbes, marine organisms and their components (Sadhasivam et al 2012).…”

Green synthesis of gold nanoparticles using marine algae and evaluation of their catalytic activity

“…The emphasis in this approach is on the synthesis and application of the nanoparticles for a maximum societal benefit, with minimal impact on the ecosystem [5]. As both the synthesis and applications of nanoparticles are important, many researchers from both academic and industry are focusing towards biological systems such as plants, marine algae, fungi and bacteria for the production of nanoparticles [6][7][8][9]. The compounds present in the extracts can act as reducing as well as stabilizing agents and render more biocompatibility to biosynthesized nanoparticles [10].…”