title: Aptamer based photoelectrochemical cytosensor with layer-by-layer assembly of CdSe semiconductor nanoparticles as photoelectrochemically active species.
abstract: A label-free photoelectrochemical cytosensor for highly sensitive and specific detection of Ramos cell was developed based on photoactive films. The films were fabricated by a layer-by-layer (LBL) assembly of positively charged poly(dimethyldiallylammonium chloride) (PDDA) and negatively charged CdSe semiconductor nanoparticles (NPs) capped with mercaptoacetic acid. The resulting modified electrodes were tested as sensors for Ramos cell through the recognition of DNA aptamer which was covalently bound to the electrode using the classic coupling reactions between -COOH groups on the surfaces of CdSe NPs and -NH(2) groups of the aptamer. The newly developed cytosensor exhibited excellent sensitivity and selectivity. The linear range was from 160 to 1600 cells/mL and the detection limit was 84 cells/mL.
authors.affiliation: State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
authors.forename: Xiaoru
authors.initials: X
authors.lastname: Zhang
authors.forename: Shuguo
authors.initials: S
authors.lastname: Li
authors.forename: Xia
authors.initials: X
authors.lastname: Jin
authors.forename: Xuemei
authors.initials: X
authors.lastname: Li
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D019187:Cadmium Compounds / Q000737:chemistry*; D045744:Cell Line, Tumor; D058266:Dielectric Spectroscopy / Q000379:methods*; D006801:Humans; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry*; D012680:Sensitivity and Specificity
chemical_list: D052157:Aptamers, Nucleotide; D019187:Cadmium Compounds; D018036:Selenium Compounds; C058667:cadmium selenide