title: A "turn-off" SERS assay of heparin with high selectivity based on heparin-peptide complex and Raman labelled gold nanoparticles.
abstract: Stable SERS response originating from gold nanoparticles (Au NPs) is demonstrated for the first time to be suitable for detection of heparin with high selectivity. Herein we report a novel "turn-off" SERS assay for heparin based on Raman labelled Au NPs and competitive bonding between heparin and two specialized peptides, such as RKGSGRRLVKC (11-peptide) and CALNN (5-peptide). By means of coordination interactions and other non-electrostatic forces, these 5-peptide capped Au NPs are induced to undergo controllable aggregation upon the additive of 11-peptide and heparin with a concentration range (0-2.4 U/mL), which correspondingly cause quantitative changes of SERS intensity of 4-MBA conjugated on Au NPs. The decreased Raman intensity obtained by subtracting two cases of additives which contain only 11-peptide and the mixture of 11-peptide and heparin, is proportional to the concentration of heparin over a range of 0.2-2.4 U/mL (R(2)=0.99157), with a limit of detection (LOD) of 0.042 U/mL (S/N=3:1). Moreover, the proposed highly selective method has potential application for rapid, separation-free detection of heparin in human blood serum samples.
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
authors.forename: Gan
authors.initials: G
authors.lastname: Qu
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
authors.forename: Guannan
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
authors.forename: Zitong
authors.initials: Z
authors.lastname: Wu
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China. Electronic address: agshen@whu.edu.cn.
authors.forename: Aiguo
authors.initials: A
authors.lastname: Shen
authors.affiliation: School of Physics and Technology, Center for Electron Microscopy and MOE Key Laboratory of Artificial Micro- and Nano-structures, Wuhan University, Wuhan 430072, China.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China. Electronic address: jmhu@whu.edu.cn.
authors.forename: Jiming
authors.initials: J
authors.lastname: Hu
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry*; D006493:Heparin / Q000032:analysis* / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation; D010455:Peptides / Q000737:chemistry*; D025941:Protein Interaction Mapping / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013059:Spectrum Analysis, Raman / Q000295:instrumentation*; D013194:Staining and Labeling; D020349:Surface Plasmon Resonance / Q000295:instrumentation*
chemical_list: D010455:Peptides; D006046:Gold; D006493:Heparin
keywords: Gold nanoparticles; Heparin; Heparin–peptide complex; SERS