title: Gold nanostar-enhanced surface plasmon resonance biosensor based on carboxyl-functionalized graphene oxide.
abstract: A new high-sensitivity surface plasmon resonance (SPR) biosensor based on biofunctional gold nanostars (AuNSs) and carboxyl-functionalized graphene oxide (cGO) sheets was described. Compared with spherical gold nanoparticles (AuNPs), the anisotropic structure of AuNSs, which concentrates the electric charge density on its sharp tips, could enhance the local electromagnetic field and the electronic coupling effect significantly. cGO was obtained by a diazonium reaction of graphene oxide (GO) with 4-aminobenzoic acid. Compared with GO, cGO could immobilize more antibodies due to the abundant carboxylic groups on its surface. Testing results show that there are fairly large improvements in the analytical performance of the SPR biosensor using cGO/AuNSs-antigen conjugate, and the detection limit of the proposed biosensor is 0.0375 μg mL(-1), which is 32 times lower than that of graphene oxide-based biosensor.
authors.affiliation: College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Wu
authors.affiliation: College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Sun
authors.affiliation: College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China.
authors.forename: Pinyi
authors.initials: P
authors.lastname: Ma
authors.affiliation: College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China.
authors.forename: Di
authors.initials: D
authors.lastname: Zhang
authors.affiliation: College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China.
authors.forename: Shuo
authors.initials: S
authors.lastname: Li
authors.affiliation: College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China.
authors.forename: Xinghua
authors.initials: X
authors.lastname: Wang
authors.affiliation: College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China. Electronic address: songdq@jlu.edu.cn.
authors.forename: Daqian
authors.initials: D
authors.lastname: Song
mesh_terms: D000906:Antibodies / Q000737:chemistry; D015374:Biosensing Techniques; D006046:Gold / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D007118:Immunoassay / Q000379:methods; D046529:Microscopy, Electron, Transmission; D049329:Nanostructures / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D056951:Photoelectron Spectroscopy; D013056:Spectrophotometry, Ultraviolet; D020349:Surface Plasmon Resonance / Q000295:instrumentation*
chemical_list: D000906:Antibodies; D010087:Oxides; D006046:Gold; D006108:Graphite
keywords: Carboxyl-functionalized graphene oxide; Gold nanostars; Pig IgG; Surface plasmon resonance (SPR) biosensor