title: i-Motif quadruplex DNA-based biosensor for distinguishing single- and multiwalled carbon nanotubes.
abstract: The increasing worldwide demand for carbon nanotubes (CNTs) and increasing concern regarding how to safely develop and use CNTs are requiring a low-cost, simple, and highly sensitive CNT detection assay for toxicological evaluation and environmental monitoring. However, this goal is still far from being achieved. All the current CNT detection techniques are not applicable for automation and field analysis because they are dependent on highly expensive special instruments and complicated sample preparation. On the basis of the capability of single-walled carbon nanotubes (SWNTs) to specifically induce human telomeric i-motif formation, we design an electrochemical DNA (E-DNA) sensor that can distinguish single- and multiwalled carbon nanotubes both in buffer and in cell extracts. The E-DNA sensor can selectively detect SWNTs with a direct detection limit of 0.2 ppm and has been demonstrated in cancer cell extracts. To the best of our knowledge, this is the first demonstration of a biosensing technique that can distinguish different types of nanotubes. Our work will provide new insights into how to design a biosensor for detection of carbon nanotubes.
authors.affiliation: Division of Biological Inorganic Chemistry, State Key Laboratory of Rare Earth Resource Utilization, Graduate School, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China.
authors.forename: Yinghua
authors.initials: Y
authors.lastname: Peng
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Wang
authors.forename: Yi
authors.initials: Y
authors.lastname: Xiao
authors.forename: Lingyan
authors.initials: L
authors.lastname: Feng
authors.forename: Chao
authors.initials: C
authors.lastname: Zhao
authors.forename: Jinsong
authors.initials: J
authors.lastname: Ren
authors.forename: Xiaogang
authors.initials: X
authors.lastname: Qu
mesh_terms: D001483:Base Sequence; D015374:Biosensing Techniques; D004247:DNA / Q000737:chemistry*; D054856:G-Quadruplexes; D006801:Humans; D037742:Nanotubes, Carbon / Q000737:chemistry*; D016615:Telomere / Q000737:chemistry*
chemical_list: D037742:Nanotubes, Carbon; D004247:DNA