These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Reversible electronic nanoswitch based on DNA G-quadruplex conformation: a platform for single-step, reagentless potassium detection. Author: Wu ZS, Chen CR, Shen GL, Yu RQ. Journal: Biomaterials; 2008 Jun; 29(17):2689-96. PubMed ID: 18358528. Abstract: A novel on/off electronic nanoswitch is for the first time described based on the conformational change of DNA sequence possessing a single guanine (G)-rich stretch. Here, a thiolated, amine-containing G-rich DNA sequence is immobilized on the surface of gold electrode by means of facile sulfur-gold chemistry, followed by being labeled with redox-active ferrocene molecules serving as the signaling species. The surface-confined DNA sequence is able to change its configuration between rigid tetramolecular G-quadruplex and flexible single-stranded structures. The large conformational change enables the probes to perform an inchworm like extending-shrinking motion, which is reflected by the fluctuation in current intensity that depends on the electron-transfer distance between the electrode surface and the redox labels. Since potassium ion can specifically bind to G-quadruplex, using this reagentless reusable electrochemical sensing platform, the simple, rapid and selective detection of potassium ion can be accomplished without the use of exogenous reagents. Success in the present electronic nanoswitch is expected to promote the exploitation of functional DNA-based nanosystems.[Abstract] [Full Text] [Related] [New Search]