title: Near-infrared luminescence quenching method for the detection of phenolic compounds using N-acetyl-L-cysteine-protected gold nanoparticles-tyrosinase hybrid material.
abstract: A rapid and simple near-infrared (NIR) luminescence quenching method for the detection of phenolic compounds based on combining the unique property of N-acetyl-L-cysteine-protected gold nanoparticles (NAC-AuNPs) and tyrosinase (Tyr) enzymatic reactions is described. This method relies on the luminescence quenching of NAC-AuNPs-tyrosinase (NAC-AuNPs-Tyr) hybrid material by phenolic compounds. The quinone intermediates produced from enzymatic catalytic oxidation of phenolic compounds were believed to play a major role in the luminescence quenching. Dynamic quenching mechanism was confirmed by using time-resolved luminescence spectroscopy. Optimization of the experimental parameters including the concentration of NAC-AuNPs-Tyr (20 microg/mL), excitation wavelength (450nm), pH (6.0), and temperature (20 degrees C) has been determined. A linear range 0.5 microM to 1.0 mM and a detection limit 0.1 microM of catechol were obtained under optimal conditions. The sensitivity of different phenolic compounds was compared and follows the trend: catechol>p-cresol>phenol. The proposed NIR luminescence quenching method exhibits high sensitivity, good repeatability, and long-term stability, demonstrating potential for further development to NIR luminescence phenol biosensors.
authors.affiliation: Research Center of Environmental Science and Engineering, School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan, PR China.
authors.forename: Wenjuan
authors.initials: W
authors.lastname: Dong
authors.forename: Chuan
authors.initials: C
authors.lastname: Dong
authors.forename: Shaomin
authors.initials: S
authors.lastname: Shuang
authors.forename: Martin M F
authors.initials: MM
authors.lastname: Choi
mesh_terms: D000111:Acetylcysteine / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry*; D008163:Luminescent Measurements / Q000295:instrumentation*; D014442:Monophenol Monooxygenase / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation*; D010636:Phenols / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation*
chemical_list: D010636:Phenols; D006046:Gold; D014442:Monophenol Monooxygenase; D000111:Acetylcysteine