title: Label-free and direct detection of C-reactive protein using reduced graphene oxide-nanoparticle hybrid impedimetric sensor.
abstract: For label-free and direct detection of C-reactive protein (CRP), an impedimetric sensor based on an indium tin oxide (ITO) electrode array functionalized with reduced graphene oxide-nanoparticle (rGO-NP) hybrid was fabricated and evaluated. Analytical measurements were performed to examine the properties of rGO-NP-modified ITO microelectrodes and to determine the influence upon sensory performance of using nanostructures modified for antibody immobilization and for recognition of CRP binding events. Impedimetric measurements in the presence of the redox couple [Fe(CN)6](3-/4-) showed significant changes in charge transfer resistance upon binding of CRP. The impedance measurements were highly target specific, linear with logarithmic CRP concentrations in PBS and human serum across a 1 ng mL(-1) and 1000 ng mL(-1) range and associated with a detection limits of 0.06 and 0.08 ng mL(-1) respectively.
authors.affiliation: Department of Biomedical Engineering, Gachon University, Yeonsu-gu, Incheon 406-799, Republic of Korea.
authors.forename: Ajay Kumar
authors.initials: AK
authors.lastname: Yagati
authors.affiliation: Department of Materials Science and Engineering, Yonsei University, Seodaemun-gu, Seoul 120-749, Republic of Korea.
authors.forename: Jae-Chul
authors.initials: JC
authors.lastname: Pyun
authors.affiliation: School of Integrative Engineering, Chung-Ang University, Dongjak-gu, Seoul 156-756, Republic of Korea.
authors.forename: Junhong
authors.initials: J
authors.lastname: Min
authors.affiliation: Department of Biomedical Engineering, Gachon University, Yeonsu-gu, Incheon 406-799, Republic of Korea. Electronic address: sbcho@gachon.ac.kr.
authors.forename: Sungbo
authors.initials: S
authors.lastname: Cho
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D002097:C-Reactive Protein / Q000032:analysis* / Q000276:immunology; D004563:Electrochemistry; D004566:Electrodes; D004867:Equipment Design; D006108:Graphite / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D013499:Surface Properties; D017971:Tin Compounds / Q000737:chemistry*
chemical_list: D055910:Antibodies, Immobilized; D017971:Tin Compounds; C109984:indium tin oxide; D006108:Graphite; D002097:C-Reactive Protein
keywords: C-reactive protein; Electrochemical impedance; Electrodeposition; Graphene oxide; Nanoparticle