A group of Indian scientists are developing a point-of-care test for detecting extremely low levels of homocysteine – a biomarker for cardiac and neurological disorders – which could serve as a cheaper, simpler, and effective early-screening tool for such disorders.
Even today, doctors prescribe a plasma homocysteine test to diagnose various conditions such as early onset of atherosclerosis, acute coronary heart disease, ischemic stroke, early pregnancy loss, chronic renal dysfunction, cognitive impairment, Alzheimer’s, and Parkinson’s disease.
The new diagnostic test will have far more sensitivity, allowing for earlier detection of conditions which could help in prescribing preventive treatments sooner than is currently possible.
“Since early-stage diagnosis is the first step to treat a condition, developing point-of-care (POC) assays for measuring plasma homocysteine could facilitate individualised therapy,” Dr Pabitra Chatterjee, principal scientist at Central Salt and Marine Chemicals Research Institute, and the study’s senior author told Happiest Health.
Tests to detect homocysteine levels available today are prone to interference by compounds such as cysteine, the precursor to homocysteine itself.
In a study published in the journal Chemical Communications, the scientists detailed the development of the test which selectively and directly measured homocysteine in clinical samples. They used water as a medium for the test to better mimic the body’s physiological environment, with the added advantage of making it inexpensive.
Adding homocysteine to the probe emits fluorescence which lasts for a long time, enabling a more precise detection of the compound. The test was found to exclusively detect only homocysteine in the blood making it more accurate than currently available test kits.
Their testing showed that the probe was also able to detect levels of the compound much lower than that present in healthy human blood plasma, indicating its high sensitivity. The researchers evaluated this in a study of 60 people, finding that the homocysteine levels were much higher in individuals with cardiac ailments than healthy individuals.
The team also observed that the probe worked just as well as homocysteine testing kits available today.
Dr Chatterjee said that the team is now working to complete clinical testing and third-party validation to bring their diagnostic kit to the market. He anticipates that it would take 2-3 years to do so. “The Indian healthcare market is desperately looking for an optical kit to measure homocysteine directly in blood plasma,” he added.