title: Unlabeled multi tumor marker detection system based on bioinitiated light addressable potentiometric sensor.
abstract: Multi biomarkers' assays are of great significance in clinical diagnosis. A label-free multi tumor markers' parallel detection system was proposed based on a light addressable potentiometric sensor (LAPS). Arrayed LAPS chips with basic structure of Si(3)N(4)-SiO(2)-Si were prepared on silicon wafers, and the label-free parallel detection system for this component was developed with user friendly controlling interfaces. Then the l-3,4-dihydroxyphenyl-alanine (L-Dopa) hydrochloric solution was used to initiate the surface of LAPS. The L-Dopa immobilization state was investigated by the theoretical calculation. L-Dopa initiated LAPS' chip was biofunctionalized respectively by the antigens and antibodies of four tumor markers, α-fetoprotein (AFP), carcinoembryonic antigen (CEA), cancer antigen 19-9 (CA19-9) and Ferritin. Then unlabeled antibodies and antigens of these four biomarkers were detected by the proposed detection systems. Furthermore physical and measuring principles in this system were described, and qualitative understanding for experimental data were given. The measured response ranges were compared with their clinical cutoff values, and sensitivities were calculated by OriginLab. The results indicate that this bioinitiated LAPS based label-free detection system may offer a new choice for the realization of unlabeled multi tumor markers' clinical assay.
authors: College of Information Science Technology, Nankai University, 300071, China. jiayunfang@yahoo.com.cn
authors: Yun-Fang
authors: YF
authors: Jia
authors: Chun-Ying
authors: CY
authors: Gao
authors: Jia
authors: J
authors: He
authors: Dao-Fu
authors: DF
authors: Feng
authors: Ke-Li
authors: KL
authors: Xing
authors: Ming
authors: M
authors: Wu
authors: Yang
authors: Y
authors: Liu
authors: Wen-Sheng
authors: WS
authors: Cai
authors: Xi-Zeng
authors: XZ
authors: Feng
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D015374:Biosensing Techniques / Q000379:methods*; D006801:Humans; D007980:Levodopa / Q000737:chemistry*; D008027:Light; D008968:Molecular Conformation; D056004:Molecular Dynamics Simulation; D011199:Potentiometry / Q000379:methods*; D012825:Silicon / Q000737:chemistry; D017655:Silicon Compounds / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013499:Surface Properties
chemical_list: D014408:Biomarkers, Tumor; D017655:Silicon Compounds; D007980:Levodopa; D012822:Silicon Dioxide; C032734:silicon nitride; D012825:Silicon