doi:10.1038/nindia.2014.173 Published online 24 December 2014
Researchers have fabricated a sensitive sensor that can detect minute traces of the hormone calcitonin in blood1. This hormone is secreted by the thyroid gland and can be used as a biomarker for detecting the onset of medullary thyroid cancer.
Calcitonin helps metabolise calcium by reducing its levels in blood. Previous studies had shown that this hormone is an excellent biomarker for predicting osteoporosis, thyroid cancer and other cancers. Existing techniques for detecting calcitonin employ various compounds including radioactive compounds, which are harmful to human health. In addition, these techniques are tedious and complex.
To develop a simple and effective technique for detecting calcitonin, the researchers synthesized zinc oxide nanostructures modified by a compound derived from the amino acid tyrosine. They then produced a calcitonin-imprinted electrochemical sensor by coating a pencil graphite electrode with a reducing agent, a catalyst, calcitonin molecules and the modified zinc oxide nanostructures.
The researchers evaluated the efficacy of the sensor in detecting calcitonin by performing electrochemical measurements while exposing it to solutions with different calcitonin concentrations. The sensor successfully detected calcitonin in blood samples, suggesting its suitability for clinical diagnosis. It retained its sensitivity even when stored for one month at various temperatures between 0 and 50 °C.
1. Patra, S. et al. Imprinted ZnO nanostructure-based electrochemical sensing of calcitonin: a clinical marker for medullary thyroid carcinoma. Anal. Chim. Acta 853, 271–284 (2015)