Co3O4 Nanoparticles as a Noninvasive Electrochemical Sensor for Glucose Detection in Saliva

A new noninvasive glucose sensor is developed based on Co 3 O 4 particles (Co 3 O 4 NPs), which are synthesized by a single-step hydrothermal method with uniform structure and size. The electrochemical measurements reveal that the device exhibits outstanding performance for glucose detection, achieving a maximal sensitivity of 2495.79 μ A mM − 1 cm − 2 with a high R 2 of 0.99575, a ultra-low detection limit of 9.3 nM with a signal-to-noise of 3 and linear range up to 3 mM. The noninvasive glucose sensor can respond swiftly and selectively due to the high electrocatalytic activity of Co 3 O 4 NPs. The sensor also shows its high sensitivity and selectivity in detecting glucose levels in human blood serum and saliva sample, confirming the application potential of Co 3 O 4 NPs in noninvasive detection of glucose.