G-quadruplex based biosensors for the detection of food contaminants

Abstract

G-quadruplex (G4) is a very interesting DNA structure, commonly associated with cancer and its treatment. With flexible binding ability, G4 has been extended as a significant component in biosensors. On account of its simple operation, high sensitivity and low cost, G4-based biosensors have attracted considerable interest for the detection of food contaminants. In this review, research published in recent 5 years is collated from a principle perspective, that is target recognition and signal transduction. Contaminants with G4 binding capacity are illustrated, emerging G4-based biosensors including colorimetric, electrochemical and fluorescent sensors are also elaborated. The current review indicates that G4 has provided an efficient and effective solution for the rapid detection of food contaminants. A distinctive feature of G4 as recognition unit is the simple composition, but the selectivity is still unsatisfactory. As signal reporter, G4/hemin DNAzyme has not only achieved amplified signals, but also enabled visualized detection, which offers great potential for on-site measurement. With improved selectivity and visualized signal, the combination of aptamer and G4 seems to be an ideal strategy. This promising combination should be developed for the real-time monitor of multiple contaminants in food matrix.

Keywords:

• G-quadruplex
• functional nucleic acid
• sensor
• food safety

Disclosure statement

The authors report there are no competing interests to declare.

Funding

This work was supported by the National Key Research and Development Program of China under Grant No. 2020YFC1606803; the Open Project of Engineering Research Center of Dairy Quality and Safety Control Technology (Ministry of Education of China) under Grant R202101.