title: Heterogeneous electrochemical immunoassay of hippuric acid on the electrodeposited organic films.
abstract: By directly coordinating hippuric acid (HA) to the ferrate (Fe) as an electron transfer mediator, we synthesized a Fe-HA complex, which shows a good electrochemical signal and thus enables the electrochemical immunoanalysis for HA. We electrodeposited organic films containing imidazole groups on the electrode surface and then bonded Ni ion (positive charge) to induce immobilization of Fe-HA (negative charge) through the electrostatic interaction. The heterogeneous competitive immunoassay system relies on the interaction between immobilized Fe-HA antigen conjugate and free HA antigen to its antibody (anti-HA). The electric signal becomes weaker due to the hindered electron transfer reaction when a large-sized HA antibody is bound onto the Fe-HA. However, in the presence of HA, the electric signal increases because free HA competitively reacts with the HA antibody prior to actual reaction and thus prevents the HA antibody from interacting with Fe-HA at the electrode surface. This competition reaction enabled an electrochemical quantitative analysis of HA concentration with a detection limit of 0.5 μg mL(-1), and thus allowed us to develop a simple and rapid electrochemical immunosensor.
authors.affiliation: Department of chemistry, College of Natural Science, Dankook University, Anseo-Dong, Cheonan 330-714, Korea. chem0404@dankook.ac.kr.
authors.forename: Young-Bong
authors.initials: YB
authors.lastname: Choi
authors.affiliation: Department of chemistry, College of Natural Science, Dankook University, Anseo-Dong, Cheonan 330-714, Korea. albireo0827@naver.com.
authors.forename: Nam-Hyuk
authors.initials: NH
authors.lastname: Kim
authors.affiliation: Department of chemistry, College of Natural Science, Dankook University, Anseo-Dong, Cheonan 330-714, Korea. kimsemail@dankook.ac.kr.
authors.forename: Seung-Hoi
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of biology, College of Natural Science, Dankook University, Anseo-Dong, Cheonan 330-714, Korea. gtae@dankook.ac.kr.
authors.forename: Gun-Sik
authors.initials: GS
authors.lastname: Tae
authors.affiliation: Department of chemistry, College of Natural Science, Dankook University, Anseo-Dong, Cheonan 330-714, Korea. hankim@dankook.ac.kr.
authors.forename: Hyug-Han
authors.initials: HH
authors.lastname: Kim
mesh_terms: D000906:Antibodies / Q000737:chemistry / Q000276:immunology; D000941:Antigens / Q000276:immunology / Q000302:isolation & purification; D015374:Biosensing Techniques / Q000379:methods*; D055664:Electrochemical Techniques / Q000379:methods*; D006626:Hippurates / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007501:Iron / Q000737:chemistry*; D057230:Limit of Detection; D009532:Nickel / Q000737:chemistry; D014050:Toluene / Q000737:chemistry
chemical_list: D000906:Antibodies; D000941:Antigens; D006626:Hippurates; C017311:ferrate ion; D014050:Toluene; D009532:Nickel; D007501:Iron; C030514:hippuric acid