• 文献标题:   Amplified using DNase I and aptamer/graphene oxide for sensing prostate specific antigen in human serum
  • 文献类型:   Article
  • 作  者:   FANG BY, WANG CY, LI C, WANG HB, ZHAO YD
  • 作者关键词:   amplified fluorescence assay, quantum dot conjugated aptamer, grapheme oxide, prostate specific antigen
  • 出版物名称:   SENSORS ACTUATORS BCHEMICAL
  • ISSN:   0925-4005
  • 通讯作者地址:   Huazhong Univ Sci Technol
  • 被引频次:   19
  • DOI:   10.1016/j.snb.2017.01.045
  • 出版年:   2017

▎ 摘  要

In this paper, we proposed an amplified assay using DNase I for sensitively sensing prostate specific antigen (PSA) based on CdSe/ZnS quantum dot labelled PSA aptamer/graphene oxide (QD-aptamer/GO). In this sensing system, GO could strongly bind QD conjugated aptamer and quench the fluorescence of QD, furthermore, GO could protect DNA from nuclease cleavage. When binding target PSA, aptamer probe released from the surface of GO nanosheet, then the free aptamer could be cleaved by nuclease, thus the QD and PSA were liberated, after that, the released PSA would bind another aptamer on GO nanosheet and start a new cycle, which resulted in amplification of restoring signal. The probe possessed steady fluorescence signal and high specificity due to the anti photobleaching of QD and the high affinity of aptamer to PSA. Under the optimum experimental conditions, fluorescence intensity increased linearly with the PSA concentration between 0.1 fgmL(-1) and 3 fgmL(-1) with the limit of quantification of 0.05 fgmL(-1), which was three orders of magnitude lower than that without DNase I. Finally, the method was applied to quantification of PSA in human serum samples. (C) 2017 Elsevier B.V. All rights reserved.