DNA nanostructures articles within NPG Asia Materials

Featured

• Original Article
  26 September 2014 | Open Access

  Polymerase/nicking enzyme synergetic isothermal quadratic DNA machine and its application for one-step amplified biosensing of lead (II) ions at femtomole level and DNA methyltransferase

  We constructed a novel and universal biosensing platform based on polymerase-nicking enzyme synergetic isothermal quadratic DNA machine (ESQM). It tactfully integrates two signal amplification modules including strand displacement amplification (SDA) and nicking enzyme signal amplification (NESA) into a one-step biosensing system via a bifunctional DNA probe with stem-loop structure. ESQM can be activated to afford a high amplified signal in the presence of target. The ultrasensitive detection of Pb²⁺ (30 fM) even in real water sample was achieved within 40 min, and the practicability of ESQM in DNA methyltransferase activity analysis demonstrated the universality of this biosensing platform.

  • Yongxi Zhao
  • , Feng Chen
  •  & Chunhai Fan

• Original Article
  11 July 2014 | Open Access

  Ultrasensitive IgG quantification using DNA nano-pyramids

  Four oligonucleotide strands are hybridized to form the 3D DNA nano-pyramid. Three thiol groups-terminated vertex can immobilize the pyramid firmly onto the surface of gold electrode, while the remaining non-thiolated vertex at the top with carboxyl group allows the covalent binding of anti-IgG antibody. Through traditional sandwich immunoreaction, the electroactive tag, ferrocene (FeC) generates electrochemical signals used to detect the analyte IgG. The pyramidal structure with higher rigidity encourages more uniform surface assembly and less steric effect, resulting in lower background interference. The pyramid's hollow structure further contributes to efficient electron transfer and makes this immunoassay system achieve an ultrasensitive detection limit.

  • Liang Yuan
  • , Marcella Giovanni
  •  & David Tai Leong

• Review
  14 June 2013 | Open Access

  Scaffolded biosensors with designed DNA nanostructures

  Along with the rapid merge and development of biotechnology and nanotechnology, various DNA nanostructure scaffolds have been designed, characterized and exploited for a range of applications. Particularly, we have seen the evolution of surface-confined DNA probes with rational design from one-dimensional to two-dimensional and then to three-dimensional, which greatly improve our ability to control the density, orientation and passivation of the surface. In this review, we aim to summarize recent progress on the improvement of probe–target recognition properties by introducing DNA nanostructure scaffolds. A range of new strategies have proven to provide significantly enhanced spatial positioning range and accessibility of the probes on surface over previously reported linear structures. We will also describe applications of DNA nanostructure scaffold-based biosensors.

  • Hao Pei
  • , Xiaolei Zuo
  •  & Chunhai Fan