Maysam Ashrafi - Department of Chemistry, University of Kurdistan, Sanandaj, Iran
Abdollah Salimi - Department of Chemistry, University of Kurdistan, Sanandaj, Iran
Abbas Arabzadeh - Department of Chemistry, University of Kurdistan, Sanandaj, Iran

Facile and sensitive detection of glucose still is a challenge for analysts. Enzymatic and nonenzymatic electrochemical methods using graphene based modified electrodes are simple,available and general technique for glucose measurement (1). Enzymatic glucose sensors are popular due to their high sensitivity and selectivity toward glucose detection. Complicated immobilization procedures, long-term stability and high cost of enzymes are disadvantageousthis kind of biosensors. Furthermore, glucose enzyme sensors can be easily affected by humidity, temperature and pH (2). As a result, more attempts focused on advance the non-enzymaticglucose biosensors based on transition metal, alloys, metal oxides and their composites withgraphene (3). The current work describe the photoelectrocatalytic detection of glucose based on Finny Ball nanostructure (FBNs) of cobalt oxide (CoOx) which have been electrodeposited oncadmium sulfide nanoparticles /reduced graphene oxide composite (CdS/rGO). When theprepared sensor is exposed under visible light, cadmium sulfide (QD) significantly improve the sensitivity and limit of detection (4). The proposed CoOx/CdS/rGO hybrid composite is wellcharacterized by scanning electron microscopy (SEM) and Energy Dispersive X-ray analysis(EDX) (Figure 1), and electrochemical impedance spectroscopy was used for measuring the electron transfer resistance. Those results confirm the integration of cadmium sulfide and cobaltoxide on the graphene substrate. Glucose sensing was investigated by both cyclic Voltammetry (CV) and amperometry techniques (Figure 2). The linear dynamic range and limit of detection were 1-10 and 10-1030 μM and 0.33 μM, respectively. This methodology can be used for developing glucose optical sensors with improved sensitivity.

Electrodeposition; Cobalt oxide; Glucose detection; CdS Quantum Dots