title: Highly sensitive and selective detection of cancer cell with a label-free electrochemical cytosensor.
abstract: Electrochemical methods have attracted considerable attention for developing cytosensing system since they can decrease the cost and time requirement for cell detection with simple instrumentation. Herein, a label-free electrochemical cytosensor with surface-confined ferrocene as signal indicator was developed for highly sensitive and selective detection of cancer cell. With layer-by-layer (LBL) self-assembly technique, positively charged poly(ethylene imine) functionalized with ferrocene (Fc-PEI) and negatively charged single-wall carbon nanotubes (SWNTs) were alternately assembled on 3-mercaptopropionic acid (MPA) modified gold substrate. Folic acid (FA) was covalently bonded onto SWNTs surface to specifically recognize cancer cells according to the high affinity of FA for folate receptor (FR) on cellular surface. The developed cytosensor presented high sensitivity and selectivity for the detection of human cervical carcinoma (HeLa) cell. By using fast-response differential pulse voltammetry (DPV) method, a wide detection range from 10 to 10(6) cells/mL with a detection limit as low as 10 cells/mL was reached even in the presence of a large amount of non-cancerous cells.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
authors.forename: Jiyang
authors.initials: J
authors.lastname: Liu
authors.forename: Yinan
authors.initials: Y
authors.lastname: Qin
authors.forename: Dan
authors.initials: D
authors.lastname: Li
authors.forename: Tianshu
authors.initials: T
authors.lastname: Wang
authors.forename: Yaqing
authors.initials: Y
authors.lastname: Liu
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.forename: Erkang
authors.initials: E
authors.lastname: Wang
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D003581:Cytodiagnosis / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006367:HeLa Cells; D006801:Humans; D009374:Neoplasms, Experimental / Q000175:diagnosis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013194:Staining and Labeling