title: Metal-enhanced fluorescent detection for protein microarrays based on a silver plasmonic substrate.
abstract: This paper presents an ultrasensitive fluorescent detection method through fabricating a silver microarray substrate. Silver nanoparticles (AgNPs) and Ag@Au core-shell nanoparticles with different sizes were first synthesized by a seed-mediated growth method and the metal-enhanced fluorescence of these nanoparticles on different fluorescent dyes was investigated. The results indicated that AgNPs could act as a versatile and effective metal-enhanced fluorescence material for various fluorophores, whereas the enhanced fluorescence from Ag@Au was limited only to certain fluorophores. When the AgNPs were functionalized with aptamers and fluorescent dyes, a good analytical performance for simultaneous detection of human IgE and platelet-derived growth factor-BB (PDGF-BB) could be obtained. AgNPs were not only used as detection tags but also used to fabricate the plasmonic microarray substrate to further enhance the sensitivity of fluorescent detection. As a result, a linear response to PDGF-BB concentration was obtained in the concentration range of 16 pg mL(-1) to 50 ng mL(-1), and the detection limit was 3.2 pg mL(-1). In addition, the AgNP modified plasmonic microarrays showed remarkable recovery and no significant interference from human serum when applied to 2 ng mL(-1) PDGF-BB concentration. The plasmonic microarray substrate demonstrated both high specificity and sensitivity for protein microarray detection and this novel approach has great potential for ultrasensitive detection of protein biomarkers in the bio-medical field.
authors: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, China. xudanke@nju.edu.cn.
authors: Hui
authors: H
authors: Li
authors: Min
authors: M
authors: Wang
authors: Weibing
authors: W
authors: Qiang
authors: Hongting
authors: H
authors: Hu
authors: Wei
authors: W
authors: Li
authors: Danke
authors: D
authors: Xu
mesh_terms: D000077214:Becaplermin; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry*; D006801:Humans; D007073:Immunoglobulin E / Q000032:analysis*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D040081:Protein Array Analysis / Q000295:instrumentation / Q000379:methods*; D020574:Proto-Oncogene Proteins c-sis / Q000032:analysis*; D012680:Sensitivity and Specificity; D012834:Silver / Q000737:chemistry*; D020349:Surface Plasmon Resonance
chemical_list: D005456:Fluorescent Dyes; D020574:Proto-Oncogene Proteins c-sis; D000077214:Becaplermin; D007073:Immunoglobulin E; D012834:Silver