title: Biocompatible gold nanorods: one-step surface functionalization, highly colloidal stability, and low cytotoxicity.
abstract: The conjugation of gold nanorods (AuNRs) with polyethylene glycol (PEG) is one of the most effective ways to reduce their cytotoxicity arising from the cetyltrimethylammonium bromide (CTAB) and silver ions used in their synthesis. However, typical PEGylation occurs only at the tips of the AuNRs, producing partially modified AuNRs. To address this issue, we have developed a novel, facile, one-step surface functionalization method that involves the use of Tween 20 to stabilize AuNRs, bis(p-sulfonatophenyl)phenylphosphine (BSPP) to activate the AuNR surface for the subsequent PEGylation, and NaCl to etch silver from the AuNRs. This method allows for the complete removal of the surface-bound CTAB and the most active surface silver from the AuNRs. The produced AuNRs showed far lower toxicity than other methods to PEGylate AuNRs, with no apparent toxicity when their concentration is lower than 5 μg/mL. Even at a high concentration of 80 μg/mL, their cell viability is still four times higher than that of the tip-modified AuNRs.
authors: †School of Chemistry and Australian Centre for NanoMedicine, The University of New South Wales, Sydney, NSW 2052, Australia.|§ARC Training Centre for Advanced Technologies in Food Manufacture (ATFM), School of Chemical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia.
authors: Kang
authors: K
authors: Liu
authors: †School of Chemistry and Australian Centre for NanoMedicine, The University of New South Wales, Sydney, NSW 2052, Australia.
authors: Yuanhui
authors: Y
authors: Zheng
authors: †School of Chemistry and Australian Centre for NanoMedicine, The University of New South Wales, Sydney, NSW 2052, Australia.
authors: Xun
authors: X
authors: Lu
authors: ‡Department of Materials Engineering, Monash University, Wellington Road, Clayton, Victoria 3800, Australia.
authors: Thibaut
authors: T
authors: Thai
authors: §ARC Training Centre for Advanced Technologies in Food Manufacture (ATFM), School of Chemical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia.
authors: Nanju Alice
authors: NA
authors: Lee
authors: ‡Department of Materials Engineering, Monash University, Wellington Road, Clayton, Victoria 3800, Australia.
authors: Udo
authors: U
authors: Bach
authors: †School of Chemistry and Australian Centre for NanoMedicine, The University of New South Wales, Sydney, NSW 2052, Australia.|∥ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia.
authors: J Justin
authors: JJ
authors: Gooding
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D003102:Colloids; D006046:Gold / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D043942:Nanotubes / Q000737:chemistry* / Q000633:toxicity; D010720:Phosphines / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry*; D011136:Polysorbates / Q000737:chemistry; D012834:Silver / Q000737:chemistry; D012965:Sodium Chloride / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D002593:Cetrimonium Compounds; D003102:Colloids; D010720:Phosphines; D011136:Polysorbates; D013438:Sulfhydryl Compounds; C512553:bis(p-sulfonatophenyl)phenylphosphine; D012834:Silver; D011092:Polyethylene Glycols; D012965:Sodium Chloride; D006046:Gold; D000077286:Cetrimonium