Featured Research

from universities, journals, and other organizations

Adenine 'Tails' Make Tailored Anchors For DNA

Date:
December 29, 2006
Source:
National Institute of Standards and Technology
Summary:
Researchers from NIST, the Naval Research Laboratory and the University of Maryland have demonstrated a deceptively simple technique for chemically bonding single strands of DNA to gold. The technique offers a convenient way to control the density of the DNA strands on the substrate, which could be important for optimizing DNA sensor arrays.

Single-strand DNA can be anchored to a gold substrate for use in biodetectors by attaching a tail of adenine bases. Adenine's strong affinity for gold not only bonds the strands in place but also allows some control over the spacing by adjusting the length of the tail.
Credit: NIST

Researchers from the National Institute of Standards and Technology (NIST), the Naval Research Laboratory (NRL) and the University of Maryland (UMD) have demonstrated a deceptively simple technique for chemically bonding single strands of DNA to gold. Among other features, they report in a forthcoming issue* of the Proceedings of the National Academy of Sciences, the technique offers a convenient way to control the density of the DNA strands on the substrate, which could be important for optimizing DNA sensor arrays.

Related Articles


Short DNA sequences arrayed on substrates like glass, silicon or gold are used in biochemical sensors that can detect specific "target" sequences of DNA or analyze complex sequences. In such arrays, DNA strands are attached to the substrate by one end and stand up like bristles on a brush. Specific "target" DNA sequences from a test sample can be identified because they will bond (hybridize) only to a complementary sequence on the array--microarray "gene chips" are the best-known example of the technology. The properties of gold are well-known, so it is a practicaland convenient substrate for some sensors. One popular technique for making DNA sensors (developed at NIST) is to use DNA with a sulfur atom attached to one end, which acts as "glue" because sulfur readily reacts with gold.

But a potentially less expensive and even simpler approach, according to the NIST, NRL and UMD team, might be to use a string of adenine nucleotides as an anchor. Of the four nucleotides that comprise DNA molecules, adenine, turns out to have a particularly high affinity for gold. Short strands composed entirely of adenine will adhere to a gold surface even if they have to muscle aside other strands in the process. As a result, say the researchers, short blocks of adenine at the end of DNA strands can serve as bonding anchors--but even better, they say, these adenine blocks can be used to control the spacing of the DNA strands on the substrate. This is because each adenine tail lies flat on the substrate, taking up space. Within limits, the longer the adenine tail is, the larger is its footprint on the substrate, and the lower the total density of DNA strands.

Controlling the density of DNA "brushes" on a substrate is important for sensor design because an overly dense thicket does not leave enough room for "target" DNA strands from the test sample to bond, while too sparse an array doesn't produce a strong enough signal.

The authors have applied for a patent on the technique. The research was supported by Office of Naval Research and the Air Force Office of Scientific Research.

*A. Opdahl, D. Petrovykh, H. Kimura-Suda, M.J. Tarlov and L.J. Whitman. Independent control of grafting density and conformation of single-stranded DNA brushes. Proceedings of the National Academy of Sciences, 104:9-14 (2007) (Appears on-line in PNAS Early Edition.)


Story Source:

The above story is based on materials provided by National Institute of Standards and Technology. Note: Materials may be edited for content and length.


Cite This Page:

National Institute of Standards and Technology. "Adenine 'Tails' Make Tailored Anchors For DNA." ScienceDaily. ScienceDaily, 29 December 2006. <www.sciencedaily.com/releases/2006/12/061223092622.htm>.
National Institute of Standards and Technology. (2006, December 29). Adenine 'Tails' Make Tailored Anchors For DNA. ScienceDaily. Retrieved November 27, 2014 from www.sciencedaily.com/releases/2006/12/061223092622.htm
National Institute of Standards and Technology. "Adenine 'Tails' Make Tailored Anchors For DNA." ScienceDaily. www.sciencedaily.com/releases/2006/12/061223092622.htm (accessed November 27, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Thursday, November 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pet Dogs to Be Used in Anti-Ageing Trial

Pet Dogs to Be Used in Anti-Ageing Trial

Reuters - Innovations Video Online (Nov. 26, 2014) Researchers in the United States are preparing to discover whether a drug commonly used in human organ transplants can extend the lifespan and health quality of pet dogs. Video provided by Reuters
Powered by NewsLook.com
Today's Prostheses Are More Capable Than Ever

Today's Prostheses Are More Capable Than Ever

Newsy (Nov. 26, 2014) Advances in prosthetics are making replacement body parts stronger and more lifelike than they’ve ever been. Video provided by Newsy
Powered by NewsLook.com
From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

Newsy (Nov. 25, 2014) The US FDA is announcing new calorie rules on Tuesday that will require everywhere from theaters to vending machines to include calorie counts. Video provided by Newsy
Powered by NewsLook.com
Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Newsy (Nov. 25, 2014) Need another reason to eat yogurt every day? Researchers now say it could reduce a person's risk of developing type 2 diabetes. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins