title: Amperometric detection of catechol using tyrosinase modified electrodes enhanced by the layer-by-layer assembly of gold nanocubes and polyelectrolytes.
abstract: A novel amperometric biosensor for catechol was developed using the layer-by-layer (LbL) self-assembly of positively charged hexadecyltrimethylammonium stabilized gold nanocubes (AuNCs), negatively charged poly(sodium 4-styrenesulfonate) and tyrosinase on a screen printed carbon electrode (SPCE). A carboxylic acid terminated alkanethiol assembled on electrochemically deposited Au nanoparticles on a SPCE was used as a platform for LbL assembly. Each SPCE sensor surface was terminated with tyrosinase and the electrocatalytic response due to the tyrosinase reaction with catechol was measured using cyclic voltammetry and square wave voltammetry (SWV). The effect of introducing AuNCs into the LbL assembly to further enhance the catechol detection performance was then investigated by comparing the SWV results to those from biosensors created using both the tyrosinase modified LbL assembly in the absence of NCs and the covalent attachment of tyrosinase. A wide dynamic range from 10nM to 80 µM of catechol with an excellent sensitivity of 13.72 A/M and a detection limit of 0.4 nM were both achieved alongside a good selectivity and reproducibility for the AuNC-modified electrodes. As a demonstration, the optimized biosensor design was applied to determine catechol concentrations in tea samples.
authors.affiliation: Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, 1370 Sankyuk-dong, Buk-gu, Daegu 702-701, Republic of Korea.
authors.forename: Md Nurul
authors.initials: MN
authors.lastname: Karim
authors.affiliation: Center for Theragnosis, Biomedical Research Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791, Republic of Korea.
authors.forename: Ji Eun
authors.initials: JE
authors.lastname: Lee
authors.affiliation: Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, 1370 Sankyuk-dong, Buk-gu, Daegu 702-701, Republic of Korea. Electronic address: hyejinlee@knu.ac.kr.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Lee
mesh_terms: D000363:Agaricales / Q000201:enzymology*; D015374:Biosensing Techniques / Q000295:instrumentation*; D002396:Catechols / Q000032:analysis*; D055664:Electrochemical Techniques / Q000295:instrumentation; D004566:Electrodes; D004573:Electrolytes / Q000737:chemistry; D004800:Enzymes, Immobilized / Q000737:chemistry*; D004867:Equipment Design; D006046:Gold / Q000737:chemistry*; D057230:Limit of Detection; D014442:Monophenol Monooxygenase / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D015203:Reproducibility of Results; D013662:Tea / Q000737:chemistry
chemical_list: D002396:Catechols; D004573:Electrolytes; D004800:Enzymes, Immobilized; D013662:Tea; D006046:Gold; D014442:Monophenol Monooxygenase; C034221:catechol
keywords: Amperometric biosensor; Catechol; Gold nanocubes; Layer-by-layer; Screen printed carbon electrode; Tyrosinase