The Central University of Kerala has created a paper-printed strip-based colorimetric sensor that will help patients to detect and quantify variation in sodium levels sitting at home.
The strip has been developed by a team of researchers in the Department of Physics in collaboration with the Department of Biochemistry and Molecular Biology at the university.
Swapna S. Nair, associate professor, Physics Department, says estimation of sodium in the body assumes relevance owing to its physiological importance. Any deviation from the normal sodium level causes serious health problems such as hypernatremia, hyponatremia, stroke, kidney, and other problems. The continuous monitoring of sodium is advisable in such case and is required more often in elderly persons.
Ms. Nair says quantification of sodium levels in body fluids assumes great clinical relevance. But, interfering ions such as potassium is a major hurdle in sodium detection.
But the researchers were able to overcome this with clusters of 3–9 nanometer-sized copper-curcumin nanoparticles developed and printed on paper strips. The strips show high specific selectivity for sodium and the sensor not only detects but also quantifies the sodium content in both urine and blood, she says.
Although other detection techniques for the estimation of sodium in blood and urine exist, they are sophisticated techniques based on ion-selective electrodes or ion chromatography.
These methods have an inherent drawback as they often require clinical intervention. Apart from complex procedures, their high cost and high sample requirement limit their employability as point-of-care self diagnosis, she says.
To this end, paper-based sensor strips developed here are cost-effective user-friendly alternatives that can give rapid results. These strips are fabricated and calibrated for the sensing of sodium in the physiological range and shade cards were developed as a calorimetric guide for estimation of sodium, which makes them ideal point-of-care diagnostic platform to detect variation in normal sodium, she says.
The work, published in Scientific Reports (Nature Publishing groups), has gained international attention and is being considered a major invention.
The researchers, including Nelli Chandran, Prajit Janardhanan, Manikanta Bayal, Rajendra Pilankatta and Swapna S, Nair, have decided to apply the invention for patent.
