title: Localized Surface Plasmon Resonance (LSPR)-Coupled Fiber-Optic Nanoprobe for the Detection of Protein Biomarkers.
abstract: Here is presented a miniaturized, fiber-optic (FO) nanoprobe biosensor based on the localized surface plasmon resonance (LSPR) at the reusable dielectric-metallic hybrid interface with a robust, gold nano-disk array at the fiber end facet. The nanodisk array is directly fabricated using electron beam lithography (EBL) and metal lift-off process. The free prostate-specific antigen (f-PSA) has been detected with a mouse anti-human prostate-specific antigen (PSA) monoclonal antibody (mAb) as a specific receptor linked with a self-assembled monolayer (SAM) at the LSPR-FO facet surfaces. Experimental investigation and data analysis found near field refractive index (RI) sensitivity at ~226 nm/RIU with the LSPR-FO nanoprobe, and demonstrated the lowest limit of detection (LOD) at 100 fg/mL (~3 fM) of f-PSA in PBS solutions. The SAM shows insignificant nonspecific binding to the target biomarkers in the solution. The control experimentation using 5 mg/mL bovine serum albumin in PBS and nonspecific surface test shows the excellent specificity and selectivity in the detection of f-PSA in PBS. These results indicate important progress toward a miniaturized, multifunctional fiber-optic technology that integrates informational communication and sensing function for developing a high-performance, label-free, point-of-care (POC) device.
authors.affiliation: Department of Nanoscience, Joint School of Nanoscience and Nanoengineering (JSNN), University of North Carolina at Greensboro, 2907 East Gate City Blvd, Greensboro, NC, 27410, USA. j_wei@uncg.edu.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Wei
authors.affiliation: Department of Nanoscience, Joint School of Nanoscience and Nanoengineering (JSNN), University of North Carolina at Greensboro, 2907 East Gate City Blvd, Greensboro, NC, 27410, USA.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zeng
authors.affiliation: Center for Applied Optics, University of Alabama at Huntsville, Huntsville, AL, 35899, USA. liny@uah.edu.
authors.forename: Yongbin
authors.initials: Y
authors.lastname: Lin
mesh_terms: D015415:Biomarkers; D014408:Biomarkers, Tumor; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D004867:Equipment Design; D005336:Fiber Optic Technology / Q000295:instrumentation; D006801:Humans; D015336:Molecular Probe Techniques; D015335:Molecular Probes; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods*; D040901:Proteomics / Q000295:instrumentation / Q000379:methods*; D012680:Sensitivity and Specificity; D020349:Surface Plasmon Resonance / Q000295:instrumentation / Q000379:methods*
chemical_list: D015415:Biomarkers; D014408:Biomarkers, Tumor; D015335:Molecular Probes
keywords: Au nanodisk array; Fiber optics; Localized surface plasmon resonance (LSPR); Nanofabrication; Protein biomarker biosensors; Signal transduction