title: Homogenous growth of gold nanocrystals for quantification of PSA protein biomarker.
abstract: We report on another alternative sensing platform for the detection of protein biomarker (PSA-ACT complex) based on homogenous growth of Au nanocrystals in solution phase. The immuno-recognition event is translated into the gold nanoparticle growth signal which can be intuitively recognized by an unaided eye, or quantitatively measured by an UV-vis spectrophotometric analysis. Surface plasmonic signature and kinetics of the Au nanogrowth in the homogenous phase containing of HAuCl(4), AA, and CTAB have also been studied to provide suitable parameters for the immunoassay. As a result, detection limit of PSA-ACT complex was determined to be 10fM. The result indicated that this is a very sensitive, robust, simple, and economic strategy to detect protein biomarkers, and it has great potential to detect other biological interactions.
authors.affiliation: Nano-optics and Biomolecular Engineering National Laboratory, Department of Chemical Engineering, Sungkyunkwan University, Suwon 440-746, Republic of Korea.
authors.forename: Cuong
authors.initials: C
authors.lastname: Cao
authors.forename: Xinxing
authors.initials: X
authors.lastname: Li
authors.forename: Jeewon
authors.initials: J
authors.lastname: Lee
authors.forename: Sang Jun
authors.initials: SJ
authors.lastname: Sim
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood*; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D001774:Blood Chemical Analysis / Q000295:instrumentation*; D003460:Crystallization / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry*; D018189:Immunomagnetic Separation / Q000295:instrumentation* / Q000379:methods; D049329:Nanostructures / Q000737:chemistry*; D017430:Prostate-Specific Antigen / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D020349:Surface Plasmon Resonance / Q000295:instrumentation* / Q000379:methods
chemical_list: D014408:Biomarkers, Tumor; D006046:Gold; D017430:Prostate-Specific Antigen