Gold-DNA Combination May Lead To New Ways To Detect Diseases

August 22, 1997

Evanston, Ill. --- Researchers at Northwestern University have combined gold and DNA in an innovative way that should lead to new techniques for detecting many

types of diseases. Screening for genetic and pathogenic diseases -- that is, those transmitted through heredity and those transmitted by microorganisms -- may be done using the new material, according to one of its inventors, Chad A. Mirkin, professor of chemistry at Northwestern.

Research results reported in today's issue of Science magazine show that the procedure has a consistently high level of accuracy. "This process is likely to be faster, cheaper and more selective than existing diagnostic tools," Mirkin said. The new material is a probe made up of gold nanoparticles combined with oligonuceotides, strands of artificial DNA. Placing strands of a target DNA into a solution of the gold-DNA probes induces a chemical reaction that can be seen as a change in color from red to blue if genes linked to a particular disease are present. This color change can be readily sen en n the presence of bodily fluids such as urine or saliva.

Currently, diagnosis of such diseases frequently requires the use of radioactive phosphorus or sulfur tracers in the probes. This requires specially trained personnel, creates disposal problems and uses material with short shelf lives. Using the new gold-DNA probes eliminates those problems, because no radioactive materials are used, and the solution is stabilized to give it the longer shelf life needed for a useful diagnostic tool.

The new findings expand on earlier research by the Northwestern group, which develped the process for tailoring the optical, electrical, mechanical and structural properties of the gold-DNA combination material. Nanoparticles have a diameter one-billionth of a meter, so small they can't be seen with conventional microscopes.

Mirkin, a materials chemist, and his colleague, Robert Letsinger, chemistry professor emeritus, have been developing the technique for several years. Letsinger is a pioneer in the fabrication of artificial DNA. In addition to Mirkin and Letsinger, co-authors of the Science paper are post-doctoral assistant Robert Elghanian and graduate students James J. Storhoff and Robert C. Mucic.

In addition to medical diagnosis, the new material could be used for analysis in forensics, mass screenings for pathogens in clinical or laboratory settings and detection of biological weapons, Mirkin said.

Northwestern University

Related DNA Articles from Brightsurf:

A new twist on DNA origami
A team* of scientists from ASU and Shanghai Jiao Tong University (SJTU) led by Hao Yan, ASU's Milton Glick Professor in the School of Molecular Sciences, and director of the ASU Biodesign Institute's Center for Molecular Design and Biomimetics, has just announced the creation of a new type of meta-DNA structures that will open up the fields of optoelectronics (including information storage and encryption) as well as synthetic biology.

Solving a DNA mystery
''A watched pot never boils,'' as the saying goes, but that was not the case for UC Santa Barbara researchers watching a ''pot'' of liquids formed from DNA.

Junk DNA might be really, really useful for biocomputing
When you don't understand how things work, it's not unusual to think of them as just plain old junk.

Designing DNA from scratch: Engineering the functions of micrometer-sized DNA droplets
Scientists at Tokyo Institute of Technology (Tokyo Tech) have constructed ''DNA droplets'' comprising designed DNA nanostructures.

Does DNA in the water tell us how many fish are there?
Researchers have developed a new non-invasive method to count individual fish by measuring the concentration of environmental DNA in the water, which could be applied for quantitative monitoring of aquatic ecosystems.

Zigzag DNA
How the cell organizes DNA into tightly packed chromosomes. Nature publication by Delft University of Technology and EMBL Heidelberg.

Scientists now know what DNA's chaperone looks like
Researchers have discovered the structure of the FACT protein -- a mysterious protein central to the functioning of DNA.

DNA is like everything else: it's not what you have, but how you use it
A new paradigm for reading out genetic information in DNA is described by Dr.

A new spin on DNA
For decades, researchers have chased ways to study biological machines.

From face to DNA: New method aims to improve match between DNA sample and face database
Predicting what someone's face looks like based on a DNA sample remains a hard nut to crack for science.

Read More: DNA News and DNA Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.