title: Gold-nanoparticle-decorated silica nanorods for sensitive visual detection of proteins.
abstract: We report a rapid and highly sensitive approach based on gold-nanoparticle-decorated silica nanorods (GNP-SiNRs) label and lateral-flow strip biosensor (LFSB) for visually detecting proteins. Owing to its biocompatibility and convenient surface modification, SiNRs were used as carriers to load numerous GNPs, and the GNP-SiNRs were used as labels for the lateral-flow assay. The LFSB detection limit was lowered 50 times compared to the traditional GNP-based lateral-flow assay. Rabbit IgG was used as a model target to demonstrate the proof-of-concept. Sandwich-type immunoreactions were performed on the immunochromatographic strips, and the accumulation of GNP-SiNRs on the test zone produced the characteristic colored bands, enabling visual detection of proteins without instrumentation. The quantitative detection was performed by reading the intensities of the colored bands with a portable strip reader. The response of the optimized device was highly linear for the range of 0.05-2 ng mL(-1), and the detection limit was estimated to be 0.01 ng mL(-1). The GNP-SiNR-based LFSB, thus, offered an ultrasensitive method for rapidly detecting trace amounts of proteins. This method has a potential application with point-of-care screening for clinical diagnostics and biomedical research.
authors.affiliation: College of Food Science, Fujian Agriculture and Forestry University , Fuzhou, Fujian 350002, PR China.
authors.forename: Hui
authors.initials: H
authors.lastname: Xu
authors.forename: Jiao
authors.initials: J
authors.lastname: Chen
authors.forename: Joseph
authors.initials: J
authors.lastname: Birrenkott
authors.forename: Julia Xiaojun
authors.initials: JX
authors.lastname: Zhao
authors.forename: Sunitha
authors.initials: S
authors.lastname: Takalkar
authors.forename: Kwaku
authors.initials: K
authors.lastname: Baryeh
authors.forename: Guodong
authors.initials: G
authors.lastname: Liu
mesh_terms: D015374:Biosensing Techniques; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles; D008855:Microscopy, Electron, Scanning; D043942:Nanotubes; D011506:Proteins / Q000032:analysis*; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D011506:Proteins; D006046:Gold; D012822:Silicon Dioxide