Review—Fundamentals to Applications of MXenes for Biosensing

Advancement in biosensing techniques is the topmost priority in the present era of technology as the limitations of conventional methods outweighs its advantages. Hence, designing of compact, user and environmental friendly, economical and highly sensitive and responsive biosensors is need of the hour. MXenes, two-dimensional layered material, have gained a lot of attention in very less time due to its diverse properties such as enormous conductivity, meagre cellular toxicity, elaborated surface chemistry, natural hydrophilicity, magnificent optoelectronic features and ability to form stable colloidal suspensions. These properties of MXenes categorize them as a potential material for fabrication of highly efficient modern world biosensors. MXenes are synthesized via various methodologies such as etching methods, top-down and bottom-up approaches, depending upon their applications. Moreover, to study the surface structure and identify various properties and functional groups, different characterization techniques are employed including X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy etc. The surface functionalization of MXenes can be modified with polymerization, direct surface terminations etc. for enhancing the efficiency of biosensors developed from them. MXenes based biosensors have been utilized in diverse fields viz. electrochemical biosensing, optical biosensing, wearable biosensing etc. These biosensors are of prime importance for early detection of deadly diseases such as cancers of various body parts including lungs, pancreas, breast etc., and hyperglycaemia. Moreover, they play an important role for detecting environmental pollutants viz. heavy metals, nitrites, phenols etc. Hence, necessary actions can be taken on time in order to save the health and environment.