Gene transfer has many potential applications in basic and applied sciences. In vitro, DNA delivery can be enhanced by increasing the concentration of DNA in the cellular microenvironment through immobilization of DNA to a substrate that supports cell adhesion. Substrate-mediated delivery describes the immobilization of DNA, complexed with cationic lipids or polymers, to a biomaterial or substr...

Single-molecule studies of the interactions of DNA and proteins are important in a variety of biological or biotechnology processes ranging from the protein’s search for its DNA target site, DNA replication, transcription, or repair, and genome sequencing. A critical requirement for single-molecule studies is the stretching and immobilization of otherwise randomly coiled DNA molecules. Several ...

Conducting polymers (CPs) are a group of polymeric materials that have attracted considerable attention because of their unique electronic, chemical, and biochemical properties. This is reflected in their use in a wide range of potential applications, including light-emitting diodes, anti-static coating, electrochromic materials, solar cells, chemical sensors, biosensors, and drug-release syste...

Negative-charge change and conformation transition upon DNA immobilization and hybridization on functionalized graphene sheets were monitored by the EIS technique and adopted as the signal for label-free electrochemical DNA hybridization detection.

A facile and efficient method for direct immobilization of phosphorylated oligonucleotides on an epoxy-activated glass surface is described. The new immobilization strategy has been analyzed for its performance in DNA microarray under both microwave and thermal conditions. It reflects high immobilization efficiency ( approximately 23%), and signal-to-noise ratio ( approximately 98) and resulted...

We report here the in vitro selection of DNA aptamers for electric eel acetylcholinesterase (AChE). One selected aptamer sequence (R15/19) has a high affinity towards the enzyme (Kd=157±42 pM). Characterization of the aptamer showed its binding is not affected by low ionic strength (~20 mM), however significant reduction in affinity occurred at high ionic strength (~1.2 M). In addition, this ap...

This manuscript describes the surface immobilization of a light-harvesting complex to prescribed locations directed by the sequence-selective recognition of duplex DNA. An engineered light-harvesting complex (RC-LH1) derived from Rhodopseudomonas (Rps.) palustris containing the zinc finger (ZF) domain zif268 was prepared. The zif268 domain directed the binding of zfRC-LH1 to target double-stran...

Using two different 25-mer oligonucleotide probes covalently grafted on a silicon substrate, we demonstrate how efficient atomic force microscopy (AFM) can be for monitoring each step of DNA chip preparation: from probe immobilization to hybridization on the molecular scale. We observed the probe-molecule organization on the chip after immobilization, and the target molecules, which hybridized ...

Cip1-interacting zinc finger protein 1 (Ciz1) stimulates DNA replication in vitro and is required for mammalian cells to enter S phase. Here, we show that a significant proportion of Ciz1 is retained in nuclear foci following extraction with nuclease and high salt. This suggests that Ciz1 is normally immobilized by interaction with non-chromatin nuclear structures, consistent with the nuclear m...

We report a rapid, ultrasensitive, immobilization-free and signal-on electrochemical DNA biosensor with excellent discrimination ability for single-nucleotide polymorphisms. It achieves recognition signal generation by the specific cleavage function of exonuclease III and the diffusion different between oligonucleotides and mononucleotides towards a negatively charged ITO electrode surface. Mea...