Accurate Method for Measuring Nitric Oxide in Blood

Executive Summary
Researchers at the University of Virginia have developed a novel method of detecting nitric oxide (NO) levels in heme-containing samples such as blood.

Background
Blood gas analysis is typically used to determine the amount of oxygen and carbon dioxide carried in the blood. A third blood gas, nitric oxide (NO), is however not currently measured by routine analysis. NO signaling is abnormal in a variety of human diseases, including asthma, cystic fibrosis, sepsis, diabetes, pulmonary hypertension and sickle cell anemia, among others. Measurement of NO levels in the blood can aid in diagnosis for such diseases. Further, recent research has demonstrated that NO is intimately involved with red blood cells in regulating blood flow and oxygen delivery to tissues. Given NO’s important role in disease and oxygen delivery, there is an increasing need to measure NO in the blood in both research and clinical settings.

Existing methods of NO measurement are hampered by a lack of reliable assays. Frequently the assay signal is attenuated due to the autocapture of NO by iron (Fe), and extensive hemoglobin pretreatment is often necessary. In addition, the most reliable assays are expensive and cumbersome.

About the Invention
University of Virginia researchers have developed an analysis method that accurately and reliably measures NO in heme-containing samples, including blood. The method utilizes carbon monoxide (CO) to prevent interaction between NO and Fe, providing a precise NO reading. NO is produced by reduction of bonds in a sample and carried by the CO gas stream to the nitric oxide analyzer for quantification.

This invention is published as U.S. patent application 2007/0202605.

Advantages
Unlike existing alternatives, this invention:

• Offers an accurate, simple and reliable method
• Has the ability to detect NO in samples such as sweat, tears, urine, plasma, amniotic fluid, cerebrospinal fluid, semen, tissue, cells and more.
• Requires no sample pretreatment or processing