DNAzyme-based biosensor for detection of lead ion: A review

Lead ion (Pb2+) is a kind of toxic metal pollutant that widely spread in the environment, which is of serious concern to human health. So it is of great significance to develop simple, fast method for the detection of Pb2+. Up to now, a number of DNA sensors have been designed to recognize Pb2+, especially DNAzyme-based sensors have attracted much attention due to its advantages, such as high selectivity and sensitivity. In this review, we summarize the recent progress of two types of DNAzyme-based sensors for the detection of toxic Pb2+, including Pb2+-specific DNAzyme and G-quadruplex DNAzyme sensors. On the basis of the sensor transducers and their signal types, development and applications of fluorescent DNAzyme sensors, colorimetric DNAzyme sensors and electrochemical DNAzyme sensors are to be discussed in this paper. These DNAzyme-based sensors are highly sensitive and selective toward Pb2+, and has proved to be a useful tool in the potential application for on-site and real-time real sample (such as environmental and biological samples) monitoring in the future. (C) 2016 Elsevier B.V. All rights reserved.