Photoresponsive colorimetric immunoassay based on chitosan modified AgI/TiO2heterojunction for highly sensitive chloramphenicol detection.
Chloramphenicol (CAP) is an antibiotic used for a variety of infections, however, it is banned for use in food-producing animals due to its hazards to humans blood. Herein, the highly sensitive photoresponsive colorimetric immunoassay was exploited based on AgI/TiO2heterojunction nanomaterials. Firstly, chitosan modified AgI/TiO2photocatalyst (CS-AgI/TiO2) was synthesized by deposition-precipitation method, which was characterized by transmission electron microscope (TEM), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray powder diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (DRS) and Fourier transform infrared spectroscopy (FTIR). Then, by utilizing CS-AgI/TiO2labeled CAP antibody as tags, a novel competitive-type immunoassay was constructed for detection of CAP on the surface of CAP-BSA modified magnetic bead. The color development of 3,3',5,5'-tetramethylbenzidine (TMB) was obtained under visible light irradiation (λ≥420nm) and the assay was carried out in pH 3.0 ABS buffer solution by UV-Vis spectrophotometry. Under optimal conditions, the absorbance values decreased with the increasing of CAP levels in sample, which exhibited linear in the range of 0.03-12.53nM with a detection limit of 0.03nM. Meanwhile, the selectivity, repeatability, and stability were acceptable. Excitedly, no significant difference was observed for detection of the spiked CAP in the real food samples with the referenced values.
College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, China.
Honghong
H
Chang
College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, China.
Jia
J
Lv
College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, China.
Haochun
H
Zhang
College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, China. Electronic address: zhangbing01@tyut.edu.cn.
Bing
B
Zhang
College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, China.
Wenlong
W
Wei
State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China. Electronic address: qiaoy@sxicc.ac.cn.
Yan
Y
Qiao
D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D055910:Antibodies, Immobilized / Q000737:chemistry; D001560:Benzidines / Q000737:chemistry; D002384:Catalysis; D048271:Chitosan / Q000737:chemistry*; D002701:Chloramphenicol / Q000032:analysis*; D002863:Chromogenic Compounds / Q000737:chemistry; D003124:Colorimetry / Q000379:methods*; D004531:Eggs / Q000032:analysis; D005504:Food Analysis / Q000379:methods; D005506:Food Contamination / Q000032:analysis*; D006722:Honey / Q000032:analysis; D007118:Immunoassay / Q000379:methods; D007454:Iodides / Q000737:chemistry*; D008027:Light; D057230:Limit of Detection; D059346:Magnets / Q000737:chemistry; D008892:Milk / Q000737:chemistry; D055668:Photochemical Processes; D018030:Silver Compounds / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
D000900:Anti-Bacterial Agents; D055910:Antibodies, Immobilized; D001560:Benzidines; D002863:Chromogenic Compounds; D007454:Iodides; D018030:Silver Compounds; C009495:titanium dioxide; C021758:3,3',5,5'-tetramethylbenzidine; D002701:Chloramphenicol; C030584:silver iodide; D048271:Chitosan; D014025:Titanium
AgI/TiO(2) heterojunction; Chloramphenicol; Colorimetric; Immunoassay; Photoresponsive