Description of Invention:
Magnesium is essential to many physiochemical processes and plays a central role in the biochemistry of all cells. Many epidemiological studies have established close association between plasma magnesium levels and various diseases including ischaemic heart disease, hypertension, atherosclerosis, osteoporosis, neurological disorders and other chronic illnesses. However, methods and tools to measure selectively ionized magnesium levels in cell preparations or in the body with accuracy and reliability are still lacking in the market today. The present invention pertains to analytical elements and methods for the selective determination of magnesium. In particular, the present invention relates to carboxy-quinolizones and their use as magnesium indicators. Thus, the present invention provides novel fluorescent indicators that are selective for Mg2+. This invention utilizes fluorescence spectroscopy as a tool in monitoring intracellular or extracellular levels of magnesium. This is a non-invasive approach in which ion levels or ion fluxes induced by extra-cellular stimuli that can be monitored in real time. Current approaches used to measure devices to measure ionized intracellular magnesium in the body generally involve magnetic resonance spectroscopy to analyze intracellular ATP (adenosine triphosphate) signals. This approach is extremely expensive and subject to very poor accuracy. Unlike other methods and indicators, the composition and methods of this invention provide compounds with significantly increased abilities to accurately measure intracellular and extracellular Mg2+ levels in a wide variety of cells. Further, an extended application of this invention relates to the monitoring of the effects of drugs, medicines or toxins that alter the intracellular magnesium levels via changes in cellular ATP levels.
Inventors:
Robert E. London (NIEHS) Pieter Otten (NIEHS) Louis A. Levy (NIEHS)
Patent Status:
DHHS Reference No. E-067-2000/0 --
U.S. Patent 6,706,528 issued 16 Mar 2004
