Reduction of Graphene Oxide via Bacterial Respiration

Abstract

Here we present that graphene oxide (GO) can act as a terminal electron acceptor for heterotrophic, metal-reducing, and environmental bacteria. The conductance and physical characteristics of bacterially converted graphene (BCG) are comparable to other forms of chemically converted graphene (CCG). Electron transfer to GO is mediated by cytochromes MtrA, MtrB, and MtrC/OmcA, while mutants lacking CymA, another cytochrome associated with extracellular electron transfer, retain the ability to reduce GO. Our results demonstrate that biodegradation of GO can occur under ambient conditions and at rapid time scales. The capacity of microbes to degrade GO, restoring it to the naturally occurring ubiquitous graphite mineral form, presents a positive prospect for its bioremediation. This capability also provides an opportunity for further investigation into the application of environmental bacteria in the area of green nanochemistries.

An in vitro evaluation of graphene oxide reduced by Ganoderma spp. in human breast cancer cells (MDA-MB-231)

“…Reduction of GO by chemical methods seems to be promising, due to its low cost and potential for large-scale production, and it is also appropriate for chemical modification and subsequent processing; however, in chemical methods, the usage of hydrazine and hydrazine derivatives as strong reducing agents for formation of graphene can be toxic or explosive and challenging to handle for larger-scale production. 6,9 Earlier, several studies reported the production of graphene using various biological systems, such as bacterial respiration, 25 poly(allylamine), 26 potassium hydroxide, 27 polyvinyl pyrrolidone, 28 ascorbic acid, 29 sugar, 30 and baker's yeast. 31 Recently, we and other researchers developed a greener approach for synthesis of graphene using various bacteria, such as Escherichia coli, 7,32 Escherichia fergusonii, 33 and Bacillus marisflavi.…”

Facile synthesis of reduced graphene oxide/MWNTs nanocomposite supercapacitor materials tested as electrophoretically deposited films on glassy carbon electrodes

“…The preparation of graphene from graphene oxide has been achieved via the Hummers method [4] with a reducing agent such as hydrazine [5,6], hydroquinone [7], sodium borohydride (NaBH 4 ) [8], or ascorbic acid (LAA) [9]. Alternatively reduction has been induced thermally [6], or through the use of sulphur-containing compounds [10] or bacteria [11].…”

Reduction of graphene oxide by resveratrol: a novel and simple biological method for the synthesis of an effective anticancer nanotherapeutic molecule

“…6,9,[26][27][28] To overcome the aggregation and solubility problems, several polymers or surfactants have been used such as poly(sodium-4-styrenesulfonate), 29 alkaline conditions, 30 poly(N-vinyl-2-pyrrolidone), 31 and poly(allylamine). 32 Recently, biological molecules have been used to reduce GO; thus, Salas et al 33 have reported "green" reduction of GO via bacterial respiration. 33 Several microorganisms have been shown to reduce GO, including Shewanella spp., 34 Escherichia coli, 35,36 Pseudomonas aeruginosa, 13 Bacillus marisflavi, 36 and Ganoderma spp.…”

“…32 Recently, biological molecules have been used to reduce GO; thus, Salas et al 33 have reported "green" reduction of GO via bacterial respiration. 33 Several microorganisms have been shown to reduce GO, including Shewanella spp., 34 Escherichia coli, 35,36 Pseudomonas aeruginosa, 13 Bacillus marisflavi, 36 and Ganoderma spp. 9 A number of studies have also reported GO reduction using various biomolecules such as ascorbic acid, 37 amino acids, 38 glucose, 39,40 bovine serum albumin, 41 melatonin, 42 and humanin.…”