title: Ultrasound irradiation: a robust approach for direct functionalization of graphene oxide with thermal and antimicrobial aspects.
abstract: Sonochemical waves as mechanochemical energy was employed to exfoliate graphite oxide and functionalized graphene oxide (GrO), through a reaction of solvent and accountable for top-down and bottom-up approach respectively. The in situ formation of ester intermediate was inferred and a polymeric surface of GrO was further functionalized with 6-Aminoindazole (6-AIND) through sonochemical nucleophilic substitution reaction. As compared to conventional method the effect of ultrasound was verified for the direct functionalization of GrO. The conventional hazardous acylation step for functionalization of GrO was deleted in ultrasound assisted formation of f-(6-AIND) GrO nanocomposite, prepared by stereoselective exploitation of carboxyl groups at edges of GrO. The characterization has ascertained a covalent attachment of 6-AIND onto GrO surface with ATR-FTIR, XPS, SSNMR, TGA, DSC, XRD, AFM, RAMAN, EDX, SEM, BET and elemental analyzer. A weight loss in TGA depicts enhanced thermal stability of f-(6-AIND) GrO and a thermally sensitive behavior. The f-(6-AIND) GrO was studied for in vitro antimicrobial activity to ensure health and environmental safety. Antibacterial activity was identified against human pathogenic gram-positive (Staphylococcus aureus; ATCC 25923) and gram-negative bacteria (Escherichia coli; ATCC 25922). The antifungal activity was observed against Candida albicans (ATCC 10231).
authors.affiliation: School of Chemical Sciences, Central University of Gujarat, Gandhinagar 382030, India.
authors.forename: Shrikant S
authors.initials: SS
authors.lastname: Maktedar
authors.affiliation: School of Chemical Sciences, Central University of Gujarat, Gandhinagar 382030, India.
authors.forename: Shantilal S
authors.initials: SS
authors.lastname: Mehetre
authors.affiliation: School of Chemical Sciences, Central University of Gujarat, Gandhinagar 382030, India. Electronic address: mansingh50@hotmail.com.
authors.forename: Man
authors.initials: M
authors.lastname: Singh
authors.affiliation: School of Chemical Sciences, Central University of Gujarat, Gandhinagar 382030, India; School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
authors.forename: R K
authors.initials: RK
authors.lastname: Kale
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry* / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D006108:Graphite / Q000737:chemistry* / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D010087:Oxides / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013211:Staphylococcus aureus / Q000187:drug effects; D013696:Temperature; D014465:Ultrasonics
chemical_list: D000890:Anti-Infective Agents; D010087:Oxides; D012997:Solvents; D006108:Graphite
keywords: Activation energy; Antimicrobial activity; Graphene oxide; Sonochemical approach; Stereoselective functionalization; Thermal stability