title: Ultrasensitive photoelectrochemical immunoassay of antibody against tumor-associated carbohydrate antigen amplified by functionalized graphene derivates and enzymatic biocatalytic precipitation.
abstract: Tumor-associated carbohydrate antigens (TACAs) are often found on the surface of cancer cells. The determination of the carbohydrate components of glycoconjugates is challenging because of the chemical complexity of glycan chains. Through monitoring corresponding antibody, we can get a good solution for clinical diagnosis. Here breast tumor-associated carbohydrate antigens Tn were used as a model and a new photoelectrochemical biosensor for ultrasensitive detection of antibody against Tn was developed. To enhance the sensitivity, both graphene oxide and graphene were used during the construction of biosensor. Through the formation of immunocomplex and the insoluble biocatalytic precipitation (BCP) product, photocurrent intensity was decreased greatly and the antibody could be detected from 0.5 to 500 pg/mL with a detection limit of 1.0×10(-13) g/mL. At the same time, the developed biosensor showed acceptable selectivity and could be used in the complex matrix. Compared with the traditional glycoarray method, this PEC method is more sensitive (5 orders of magnitude), and thus provides another platform to monitor the immune response to carbohydrate epitopes at different stages during differentiation, metastasis, or treatment.
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China. Electronic address: zhangxr7407@126.com.
authors.forename: Xiaoru
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
authors.forename: Mingshuai
authors.initials: M
authors.lastname: Liu
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
authors.forename: Yaning
authors.initials: Y
authors.lastname: Mao
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
authors.forename: Yunpeng
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China. Electronic address: qdshyniu@163.com.
authors.forename: Shuyan
authors.initials: S
authors.lastname: Niu
mesh_terms: D000906:Antibodies / Q000032:analysis* / Q000097:blood* / Q000276:immunology; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000276:immunology*; D015374:Biosensing Techniques / Q000295:instrumentation*; D055664:Electrochemical Techniques / Q000295:instrumentation*; D004867:Equipment Design; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation; D057230:Limit of Detection
chemical_list: D000906:Antibodies; D015295:Antigens, Tumor-Associated, Carbohydrate; C040286:Tn antigen; D006108:Graphite
keywords: Graphene; Photoelectrochemical biosensor; Tn antigen; Tumor-associated carbohydrate antigens