Research On High-performance Flexible Biosensor Based On Two-dimensional Materials Of Manganese

Quantitative determination of superoxide anion(O2·-),a specific reactive oxygen species(ROS)participating in physiological and biochemical reactions is of great importance in investigating pathogenic mechanisms and preventing O2·-related diseases.So far,numerous methods for detecting O2·-have been developed and applied to biological and chemical systems.Nevertheless,it is still a great challenge to fulfil these demands,particularly for in-situ evaluating O2·-released from live cells due to the low concentration,various biological interferences and a short lifetime.Then,based on the previous studies,a surface oxygen-deficient MnTiO3 nanomaterials biomimetic enzyme was successfully synthesized.By directly combining Mn,Ti and O,the conductivity of manganese oxides can be improved.The absence of a large number of oxygen atoms on the surface with poor conductivity further improves the conductivity of the material.In addition,surface oxygen defects enhance the catalytic activity of the material by exposing a large number of active centers Mn.Therefore,the surface oxygen deficient material as a bionic enzyme towards O2·-shows a high sensitivity of 126.48?A ?M-1 cm-2,a linear detection range from 5.75-24955 nM and a detection limit as low as 1.54 nM.The performance is much higher than that of MnTiO3 nanomaterials without surface oxygen defects.As an O2·-biomimetic enzyme,Mn3(PO4)2 not only has excellent catalytic activity to O2·-,but also has good biocompatibility.Similar to metal oxides,Mn3(PO4)2 has poor electrical conductivity,which has been improved by combing with conductive materials.We present here the design and assembly of a heterostructured biomimetic enzyme by synergistically hybridizing two-dimensional(2-D)Mn3(PO4)2 nanosheets with rich active sites and TiC-MXene nanosheets with high electrical conductivity and abundant surface functional groups.Their hybridization enables strong interfacial interaction,which effectively promotes charge transfer and O2·-catalytic activity of the heterostructure.Thus,the hybrid material as a biomimetic enzyme towards o2·-exhibits a high sensitivity of 64.93 ?A ?M-1 cm-2,a long detection range from 5.75 to 25930 nM and a detection limit as low as 1.63 nM.The performance is much higher than their individual components and physical mixture as well as recently reported Mn3(PO4)2-based sensing platforms.The 2-D structure and strong interfacial interaction also enables the hybrid material a good flexibility with retained integrity after more than 100 bending cycles.The unique physiochemical properties and good biocompatibility of both Mn3(PO4)2 and Mxene enable the hybrid material for living cell assay and drug effect evaluation through real-time and quantitatively detecting cell released O2·-.