## 1 Introduction  
Non-communicable diseases (NCDs), which are not transmissible directly from one person to another, tend to be of long duration and are the result of a combination of genetic, physiological, environmental, and behavioral factors. The main types of NCDs are cardiovascular diseases, cancers, chronic respiratory diseases, and diabetes. According to the United Nations, chronic diseases kill 41 million people each year, equivalent to 71% of all deaths globally. Thus, this organization considers health a fundamental right for human and sustainable development as non-communicable diseases (NCDs) were recognized not only as a global health concern but also a threat to social and economic development [1]. Currently, almost 1 million people die from Diabetes and more than 400 million people suffer from it. An accurate detection method of glucose concentration can be an effective way to prevent and treat diabetes [2]. In this way, glucose sensors play an important role in managing the level of blood glucose in diabetic patients. Two different technologies are nowadays under development for improving glucose sensors, enzymatic and non-enzymatic devices. The former type of glucose test strips has dominated the glucose detection market since the earliest 60s. This biocatalyst provides good selectivity and sensitivity for glucose determination in a self-monitoring application [3]. Three different generations of glucose sensors are currently available. The first-generation glucose sensors depended directly on the available oxygen since this molecule was consumed by the immobilized enzymes for glucose oxidation. In the second-generation auxiliary enzymes are commonabilized with the analyte converting enzyme to improve the analytical quality and to simplify the performance. Finally, the third generation eliminates the need for a reaction media by enzyme immobilization on the electrode surface, then glucose is oxidized directly by the electrode. However, the second and third generations present problems in terms of electrons transfer and poor reproducibility [4, 5, 6, 7]. Some authors report enzyme electrodes with different configurations for glucose detection. Their results present good linear ranges and sensitivity values in accordance with different biological fluids [8; 9]. However, it is necessary to overcome barriers such as electrode reusability as long-term sensors will be the commercial leaders in the diabetes market. Attending lifespan criteria, non-enzymatic electrodes present better results than enzymatic-based sensors. The intrinsic chemical and thermal sensitivity of enzymes have stimulated researchers to explore chemically and thermally stable metal compounds as alternative sensing materials for non-enzymatic glucose detection. This type of sensor forms an oxidation layer, which catalyzes a glucose oxidation reaction, similar to that of the enzyme activity. Various materials such as noble metals, transition metals, and low-cost metals have been considered in this application. Noble metals, although they report good results in terms of linear range and sensitivity, they present major problems related to poisoning, electron transfer kinetics, and poor selectivity [10]. Transition metals and their oxides have gained much attention because of the cost-effectiveness and good catalytic performance for glucose oxidation, in terms of selectivity and sensitivity [11]. The third line of the periodic table of elements contains metals relatively inexpensive and with a rapid and sensitive response toward glucose molecules. Some examples are V, Mn, Fe, Co, Ni, Cu, and Zn [12; 13; 14]. In the case of copper, this metal has attracted much attention due to its properties: low cost, several morphologies, good electrocatalytic activity, and high surface area. Copper presents a good electrocatalytic capacity due to Cu\({}^{2+}\) and Cu\({}^{3+}\) ions, which act as a redox pair in catalytic processes [15].