Construction And Application Of A Novel Composite Surface Structure Immunosensor

Carcinoembryonic antigen(CEA)is one of the tumor markers commonly used in clinical.Current detection methods towards CEA suffer from disadvantages such as time-consuming and using complex procedures.Electrochemical immunosensors,which-combine the technology of electrochemical analysis and immunology have become one of the hot study in the field of detection.In this paper,several immuno sensors were constructed for CEA detection based on poly-dopamine(PDA).And these immunosensors were introduced nanoparticals,polymer brushes and hyperbranched polymer respectively but all immobilized anti-CEA through covalent.The main works are included as follows:1.A electrochemical immunosensor for the detection of tumor marker based on functionalized mesoporous silica nanoparticles.PDA coalting was used to modify indium tin oxide(ITO)electrode for functionalized mesoporous silica nanoparticles immobilization.The capture anti-CEA was immobilized on functionalized mesoporous silica nanoparticles.Under optimized conditions,the proposed immunosensor showed a high sensitivity and a linear range from in the range of 0.01,40.0 ng/mL with a detectico limit of 1.70 pg/mL.The assay results of clinical serum samples were in acceptable agreement with the reference values.The designed immunoassay system with ultrahigh sensitivity and efficient and economical,might have potentially broad applications in protein diagnostics and bioassay.2.Preparation of a immunosensor for tumor biomarker detection based on ATRP technique.A new electrochemical immunosensor using P(PEGMA)polymer brushes for immobilization of anti-CEA was described.The P(PEGMA)polymer brushes provided more stable chemical bonds with anti-CEA,which ensured the tumor marker would be covalently linked to ITO electrode.Th proposed immunosensor showed a high sensitivity and a linear range from 5 × 10-2 to 20 ng/mL with a low detection limit of 1.09 pg/mL.The assay results of clinical serum samples were in acceptable agreement with the reference values.The developed protocol could be easily extended to other protein detection in clinic determination.3.Electrochemical immunosensor based on hyperbranched structure for tumor biomarker detection.Acknowledging the benefits of hyperbranched structure,we constructed a new kind of immunsensor with functionalized hydroxyl-terminated hyperbranched polyester.The hyperbranched polyester was linked to the surface of ITO through covalent.And also the tumor maker was immobilized on the surface of the prepared electrode.Under the optimized conditions,the proposed immunosensor showed a linear range from 0.01 to 80 ng/mL and with a low detection limit of 2.36 pg/mL.The assay results of clinical serum samples were in acceptable agreement with the reference values.