title: Supersandwich cytosensor for selective and ultrasensitive detection of cancer cells using aptamer-DNA concatamer-quantum dots probes.
abstract: In this work, a signal amplification supersandwich strategy was developed for highly selective and sensitive detection of cancer cells using aptamer-DNA concatamer-quantum dots (QDs) probes. First of all, electrode materials denoted as MWCNTs@PDA@AuNPs were fabricated by multiwall carbon nanotubes (MWCNTs), gold nanoparticles (AuNPs), and polydopamine (PDA) using a layer-by-layer technique. Then, the prepared bases as matrices were applied to bind concanavalin A (Con A), resulting in high stability, bioactivity, and capability for cell capture. Meanwhile, aptamer-DNA concatamer-QDs were designed via DNA hybridization followed by covalent assembling, which incorporated the specific recognition of the aptamer with the signal amplification of the DNA concatamer and QDs. With aptamer-DNA concatamer-QDs as recognizing probes, the model cancer cells (CCRF-CEM cells) were detected using a MWCNTs@PDA@AuNPs modified electrode with trapped Con A by means of fluorescence and electrochemical methods. The proposed supersandwich cytosensor showed high sensitivity with the detection limit of 50 cells mL(-1). More importantly, it could distinguish cancer cells from normal cells, which indicated the promising applications of our method in clinical diagnosis and treatment of cancers.
authors: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing, China.
authors: Hongying
authors: H
authors: Liu
authors: Shouming
authors: S
authors: Xu
authors: Zhimei
authors: Z
authors: He
authors: Anping
authors: A
authors: Deng
authors: Jun-Jie
authors: JJ
authors: Zhu
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D045744:Cell Line, Tumor; D015342:DNA Probes / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D045663:Quantum Dots / Q000737:chemistry*; D014961:X-Ray Diffraction / Q000379:methods
chemical_list: D052157:Aptamers, Nucleotide; D015342:DNA Probes