Faster detection of kidney problems

A method for more rapidly detecting uric acid levels in urine and blood has been developed by Durham based scientists.

The findings are reported in the latest edition of the Royal Society of Chemistry journal Chemical Communications.

Levels of uric acid in biological fluids are a balance between synthesis in the liver and excretion in urine.

The acid is an important diagnostic marker in medicine. High levels are associated with kidney problems and gout - a condition where the acid builds up in the joints leading to pain and inflammation. Low levels can occur in people with AIDS or cancer.

Professor David Parker and a team at Durham University have developed a fluorescence detection technique using compounds of lanthanide metals. Lanthanides are heavy metals with atomic numbers between 57 and 71 in the periodic table.

The new method accurately detects the uric acid in diluted urine and serum samples and detection is now near instantaneous instead of 30 minutes plus with current techniques.

The sensing mixture is made up of two compounds called "macrocyclic complexes". One of these contains the metal terbium and emits green light, and the other europium which emits red light. 

The sensor measures the intensity of light emitted by these two complexes on interaction with the uric acid.

Prof Parker said: "In the short term we envisage that the method could be used for routine clinical analysis as the equipment required is commonly found in a modern analytical laboratory."

Professor Thorri Gunnlaugsson, an expert in lanthanide chemistry for sensing applications at Trinity College Dublin, said: "This method is fast and more reliable than the bioassay used today.

"The sensor could be used in the same way fluorescent sensors are used for critical care analysis in hospitals and ambulances."

with thanks to Alison Stoddart for the original article