title: Gold nano particle decorated graphene core first generation PAMAM dendrimer for label free electrochemical DNA hybridization sensing.
abstract: A novel first generation (G1) poly(amidoamine) dendrimer (PAMAM) with graphene core (GG1PAMAM) was synthesized for the first time. Single layer of GG1PAMAM was immobilized covalently on mercaptopropionic acid (MPA) monolayer on Au transducer. This allows cost effective and easy deposition of single layer graphene on the Au transducer surface than the advanced vacuum techniques used in the literature. Au nano particles (17.5 nm) then decorated the GG1PAMAM and used for electrochemical DNA hybridization sensing. The sensor discriminates selectively and sensitively the complementary double stranded DNA (dsDNA, hybridized), non-complementary DNA (ssDNA, un-hybridized) and single nucleotide polymorphism (SNP) surfaces. Interactions of the MPA, GG1PAMAM and the Au nano particles were characterized by Ultra Violet (UV), Fourier Transform Infrared (FTIR), Raman spectroscopy (RS), Thermo gravimetric analysis (TGA), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Cyclic Voltmetric (CV), Impedance spectroscopy (IS) and Differntial Pulse Voltammetry (DPV) techniques. The sensor showed linear range 1×10(-6) to 1×10(-12) M with lowest detection limit 1 pM which is 1000 times lower than G1PAMAM without graphene core.
authors.affiliation: Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi 630003, India.
authors.forename: K
authors.initials: K
authors.lastname: Jayakumar
authors.forename: R
authors.initials: R
authors.lastname: Rajesh
authors.forename: V
authors.initials: V
authors.lastname: Dharuman
authors.forename: R
authors.initials: R
authors.lastname: Venkatasan
authors.forename: J H
authors.initials: JH
authors.lastname: Hahn
authors.forename: S Karutha
authors.initials: SK
authors.lastname: Pandian
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D004247:DNA / Q000235:genetics*; D050091:Dendrimers / Q000737:chemistry*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry; D017403:In Situ Hybridization / Q000295:instrumentation*; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000295:instrumentation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA / Q000295:instrumentation*; D013194:Staining and Labeling
chemical_list: D050091:Dendrimers; C104700:PAMAM Starburst; D006046:Gold; D006108:Graphite; D004247:DNA