Electrochemical Biosensor for Detecting both Pb2+ and Hg2+ in Human Blood

Abstract

Many studies have demonstrated that lead ion ( Pb2+ ) and mercury ion ( Hg2+ ) are harmful to human health. Lead was found to accumulate in the kidney, leading to oxidative stress, apoptosis, and inflammation in the nephrons, and possess marked testicular toxicity. Mercury is well-known to produce nephrotoxicity, inflammatory responses and induce oxidative stress and apoptosis. These heavy metals can enter the human body in various ways, such as through skin or inhalation routes, or contaminated drinking water and food.  But heavy metal poisoning is not easy to diagnose because existing detecting measures has many disadvantages cause them can’t widely spread. So, seeking an easy way to detect them in human blood to discover lead or mercury poisoning is an unmet need. This paper develops a new reusable biosensor for detecting both Pb2+  and Hg2+  in human blood. This work is based on the reaction between guanine and  Pb2+  form of G-quadruplex and Hg2+  connect two thymines together cause the variation of electrochemical signal. The signal is magnified by methylene blue-gold nanoparticles (MB-AuNP) to increase the limit of detection Although the reuse part of sensor is still in theory, but this approach can make the cost of sensor low and create the feasibility of recycle. Overall, providing a new idea to make contributions to the prevention of heavy metal poisoning is the reason why this study is conducted.