Exploring Copper Oxide and Copper Sulfide for Non-Enzymatic Glucose Sensors: Current Progress and Future Directions

Abstract

Millions of people worldwide are affected by diabetes, a chronic disease that continuously grows due to abnormal glucose concentration levels present in the blood. Monitoring blood glucose concentrations is therefore an essential diabetes indicator to aid in the management of the disease. Enzymatic electrochemical glucose sensors presently account for the bulk of glucose sensors on the market. However, their disadvantages are that they are expensive and dependent on environmental conditions, hence affecting their performance and sensitivity. To meet the increasing demand, non-enzymatic glucose sensors based on chemically modified electrodes for the direct electrocatalytic oxidation of glucose are a good alternative to the costly enzymatic-based sensors currently on the market, and the research thereof continues to grow. Nanotechnology-based biosensors have been explored for their electronic and mechanical properties, resulting in enhanced biological signaling through the direct oxidation of glucose. Copper oxide and copper sulfide exhibit attractive attributes for sensor applications, due to their non-toxic nature, abundance, and unique properties. Thus, in this review, copper oxide and copper sulfide-based materials are evaluated based on their chemical structure, morphology, and fast electron mobility as suitable electrode materials for non-enzymatic glucose sensors. The review highlights the present challenges of non-enzymatic glucose sensors that have limited their deployment into the market.

Non-Destructive Sensor for Glucose Solution Concentration Detection Using Electromagnetic Technology

“…The interactions between glucose in blood and specific wavelength of light, the absorption, scattering and transmission characteristics of light are utilized to infer the concentration of glucose in the blood [ 11 ]. In addition, biochemical methods such as reverse ion electroosmosis [ 12 , 13 , 14 , 15 , 16 ] and bioelectrical impedance [ 17 , 18 ] are also commonly applied for non-destructive detection of blood glucose. Moreover, the microwave method is also used to measure the concentration of glucose in blood non-invasively by microwave radiation [ 19 ].…”

CuX/Sulfur-Doped C3N4 Nanocomposite-Modified Glassy Carbon Electrode for Electrochemical Detection of Dopamine

“…Additionally, the excellent performance of CuS/S-doped g-C 3 N 4 can also be attributed to the strong ability of DA to bind the synthesized nanocomposite via the oxygen−metal coordinate bond owing to the higher covalent character of CuS. 32 To the best of our knowledge, the modified glassy carbon electrode (GCE) using CuS/S-doped g-C 3 N 4 has not yet been reported before for DA detection. Furthermore, the synthesized nanocomposite CuS/S-doped g-C 3 N 4 /GCE was successfully applied as an electrocatalyst for detecting DA in human serum.…”

“…Furthermore, the close packing due to the short Cu–S distance contributes to the high electrical conductivity of these materials. Additionally, the excellent performance of CuS/S-doped g-C 3 N 4 can also be attributed to the strong ability of DA to bind the synthesized nanocomposite via the oxygen–metal coordinate bond owing to the higher covalent character of CuS . To the best of our knowledge, the modified glassy carbon electrode (GCE) using CuS/S-doped g-C 3 N 4 has not yet been reported before for DA detection.…”