Published on July 2, 2004 at 10:32 PM
A new method developed by researchers at the National Institute of Standards and Technology for accurately measuring the concentration of artificial viruses in a solution may ultimately help doctors diagnose diseases like HIV and hepatitis C earlier.
These artificial viruses are commercial standards made from the same basic chemical components in RNA (the single stranded version of DNA needed for protein synthesis.) They are constructed to be nearly identical chemically to real viruses but are encased with a protein covering to prevent degradation. The standards are currently used in research laboratories to help check analysis methods for detecting specific types of RNA, but the product has not been approved for clinical use.
What's needed according to NIST researcher Susan Krueger is a standard, reliable way to measure the concentration of artificial RNA in solution. By knowing exactly how much of the "fake" virus is present in a patient sample, a lab can better detect any additional signal caused by real virus molecules. Traditional methods for measuring concentrations don't work well with the new product since the artificial viruses are not infectious.
Instead, NIST scientists measured the concentration of artificial RNA virus solutions using a beam of neutrons as probes. As neutrons pass through the test solution, they interact in very specific ways with particular atoms, providing scientists with detailed information on molecular weight and geometry. This information can be used to very accurately measure the amount of RNA in a given solution. Precise calibration of artificial RNA concentrations may, in turn, allow laboratories to reliably detect lower concentrations of real viruses at earlier stages of infection.
http://www.nist.gov/