title: Biocompatible, nanogold-particle fluorescence enhancer for fluorophore mediated, optical immunosensor.
abstract: Fluorophores have been used as effective signal mediators for detecting biomarkers in biosamples. The enhancement of the fluorescence can, therefore, improve the sensitivity of fluorophore-mediated biosensors. A nanogold particle (NGP), when placed at an appropriate distance from a fluorophore, can effectively enhance the fluorescence by transferring the free electrons of the fluorophore, normally used for self-quenching, to the strong surface plasmon polariton field (SPPF) of the NGP. We found that some organic solvents can also enhance the fluorescence significantly. To maximize the fluorescence enhancement, novel, biocompatible nanogold particle reagents (NGPRs) were developed by combining NGPs and biocompatible solvents and tested. The level of enhancement by NGPRs was found to be additively contributed by two enhancers. These NGPRs were able to increase the signal of a fiber-optic biosensor as much as 10 times and accurately quantify some of the important cardiac markers at a tens of picomolar level. These novel enhancers are expected to be effective for fluorophore-mediated bioimaging as well as biosensing.
authors.affiliation: Department of Chemical Engineering, University of Louisville, Louisville, KY 40292, USA.
authors.forename: Bin
authors.initials: B
authors.lastname: Hong
authors.forename: Kyung A
authors.initials: KA
authors.lastname: Kang
mesh_terms: D001672:Biocompatible Materials / Q000032:analysis / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D016231:Fluorescence Polarization Immunoassay / Q000295:instrumentation* / Q000379:methods; D006046:Gold / Q000737:chemistry*; D008832:Microchemistry / Q000295:instrumentation* / Q000379:methods; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods; D020097:Natriuretic Peptide, Brain / Q000032:analysis; D055095:Optics and Photonics / Q000295:instrumentation*; D010316:Particle Size; D019210:Troponin I / Q000032:analysis
chemical_list: D001672:Biocompatible Materials; D019210:Troponin I; D020097:Natriuretic Peptide, Brain; D006046:Gold