title: Fluorescence immunosensor based on p-acid-encapsulated silica nanoparticles for tumor marker detection.
abstract: A novel, simple and highly sensitive amplified fluorescence label-free immunosensor by using p-acid-encapsulated silica nanomaterials has been developed for the first time. 4,4'-(2,5-Dimethoxy-1,4-phenylene)bis(ethyne-2,1-diyl)dibenzoic acid (p-acid) and p-acid-encapsulated silica were prepared, and characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, ultraviolet visible spectroscopy (UV-vis) and fluorescence spectroscopy. In layer-by-layer self-assembling processes using (3-aminopropyl)triethoxysilane, p-acid@SiO(2) was assembled on the glass substrate. Antibody was immobilized on the surface of p-acid@SiO(2) with N,N'-carbonyldiimidazole. The functional nanomaterials present good analytical properties with a calibration range of 0.1-100 ng mL(-1), and allow the detection of carcinoembryonic antigen (CEA) at a concentration as low as 0.04 ng mL(-1). What is important is that the as-synthesized p-acid@SiO(2) nanomaterials could be further extended for the detection of other biomarkers or biocompounds.
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong (University of Jinan), School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors.forename: Mei
authors.initials: M
authors.lastname: Yan
authors.forename: Shenguang
authors.initials: S
authors.lastname: Ge
authors.forename: Weiqiang
authors.initials: W
authors.lastname: Gao
authors.forename: Chengchao
authors.initials: C
authors.lastname: Chu
authors.forename: Jinghua
authors.initials: J
authors.lastname: Yu
authors.forename: Xianrang
authors.initials: X
authors.lastname: Song
mesh_terms: D000818:Animals; D055910:Antibodies, Immobilized / Q000737:chemistry / Q000276:immunology; D001565:Benzoates / Q000737:chemistry*; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000097:blood / Q000276:immunology; D015374:Biosensing Techniques / Q000379:methods*; D002214:Capsules; D005898:Glass / Q000737:chemistry; D006801:Humans; D007093:Imidazoles / Q000737:chemistry; D007118:Immunoassay / Q000379:methods*; D053758:Nanoparticles / Q000737:chemistry*; D019095:Point-of-Care Systems; D015203:Reproducibility of Results; D012822:Silicon Dioxide / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
chemical_list: C575102:4,4'-(2,5-dimethoxy-1,4-phenylene)bis(ethyne-2,1-diyl)dibenzoic acid; D055910:Antibodies, Immobilized; D001565:Benzoates; D014408:Biomarkers, Tumor; D002214:Capsules; D007093:Imidazoles; C006900:N,N-carbonyldiimidazole; D012822:Silicon Dioxide