title: Label-free Electrochemiluminescent Immunosensor for Detection of Prostate Specific Antigen based on Aminated Graphene Quantum Dots and Carboxyl Graphene Quantum Dots.
abstract: Prostate-specific antigen (PSA) was used as the model, an ultrasensitive label-free electrochemiluminescent immunosensor was developed based on graphene quantum dots. Au/Ag-rGO was sythsized and used as electrode material to load a great deal of graphene quantum dots due to the large surface area and excellent electron conductivity. After aminated graphene quantum dots and acarboxyl graphene quantum dots were modified onto the electrode, the ECL intensity was much high using K2S2O8 as coreactant. Then, antibody of PSA was immobilized on the surface of modified electrode surface through the adsorption of Au/Ag toward proteins, leading to the decrease of the ECL intensity. As proven by ECL spectra test and electrochemical impedance spectroscopy (EIS) analysis, the fabrication process of the immunosensor is successful. Under the optimal conditions, the ECL intensity decreased linearly with the logarithm of PSA concentration in the range of 1 pg/mL ~ 10 ng/mL. The detection limit achieved is 0.29 pg/mL. The immunosensor results were validated through the detection of PSA in serum samples with satisfactory results. Due to excellent stability, high sensitivity, acceptable repeatability and selectivity, the immunosensor has promising applications in disease and drug analysis.
authors: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors: Dan
authors: D
authors: Wu
authors: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors: Yixin
authors: Y
authors: Liu
authors: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors: Yaoguang
authors: Y
authors: Wang
authors: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors: Lihua
authors: L
authors: Hu
authors: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors: Hongmin
authors: H
authors: Ma
authors: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors: Guoqin
authors: G
authors: Wang
authors: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors: Qin
authors: Q
authors: Wei
mesh_terms: D000586:Amination; D015374:Biosensing Techniques / Q000379:methods*; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D008163:Luminescent Measurements; D008297:Male; D010316:Particle Size; D017430:Prostate-Specific Antigen / Q000378:metabolism*; D045663:Quantum Dots / Q000737:chemistry*
chemical_list: D006046:Gold; D006108:Graphite; D017430:Prostate-Specific Antigen