title: Vertical flow immunoassay (VFA) biosensor for a rapid one-step immunoassay.
abstract: A highly rapid, one-step immunoassay of high sensitivity C-reactive protein (hsCRP) using a biosensor with a vertical flow immunoassay (VFA) was developed. The VFA biosensor was primarily composed of a sample pad, conjugate pad, FTH film and nitrocellulose (NC) membrane, which were all vertically stacked upon one another. Anti-hsCRP and secondary antibodies were consecutively immobilized on the NC membrane at the position below the holes. Gold nanoparticles (AuNPs) conjugated with another anti-hsCRP antibody were encapsulated in the conjugation pad. Various assay conditions, including the size of the hole and the sample volume, were optimized. Under optimized conditions, hsCRP concentrations from 0.01 to 10 μg mL(-1) were detected within 2 min. In comparison with a lateral flow assay (LFA) system, the VFA sensor showed a gradual increase of signal in a concentration-dependent manner without a hook effect in the tested range.
authors.affiliation: Advanced Photonics Research Institute and Department of Photonics & Applied Physics (APRI), Gwangju Institute of Science & Technology, Gwangju, Korea.
authors.forename: Young Kyoung
authors.initials: YK
authors.lastname: Oh
authors.forename: Hyou-Arm
authors.initials: HA
authors.lastname: Joung
authors.forename: Sanghyo
authors.initials: S
authors.lastname: Kim
authors.forename: Min-Gon
authors.initials: MG
authors.lastname: Kim
mesh_terms: D000906:Antibodies / Q000737:chemistry / Q000276:immunology; D055910:Antibodies, Immobilized / Q000276:immunology; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D002097:C-Reactive Protein / Q000032:analysis*; D003101:Collodion / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation / Q000379:methods*; D053768:Metal Nanoparticles / Q000737:chemistry
chemical_list: D000906:Antibodies; D055910:Antibodies, Immobilized; D006046:Gold; D003101:Collodion; D002097:C-Reactive Protein