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Amperometric glucose sensors with a diameter of less than 10 μm were fabricated by the immobilization of glucose oxidase (GOx) on carbon fiber electrodes. Carbon fiber electrodes with platinum thin film were also prepared using electroplating and sputtering. The combination of electrodeposition and electropolymerization was employed for the immobilization of GOx. Although the introduction of Pt film satisfactorily improved the oxidation current of the electrode to hydrogen peroxide, sensitivities of obtained GOx-immobilized electrodes to glucose were not significant. Formation of electroplated-platinum thin film on carbon fiber was effective to reduce the influence of electroactive compounds existing in biological fluid such as ascorbic and uric acids.

In the present investigation, a glucose sensor based on conducting polyaniline nanowire electrode junction (CPNEJ) has been reported. The CPNEJ platform was modified by glucose oxidase by cross-linking in the presence of glutaraldehyde. The signal transduction mechanism of the sensor is based on the change in micro electrode junction conductance as a result of glucose oxidation induced change in the polymer redox state. Small size of CPNEJ sensor causes to regenerate enzyme naturally without need of redox mediators, as a result it consumes minimum amount of oxygen and also gives very fast response. This sensor exhibited good linear response range from 1 mM to 20 mM of glucose concentration with excellent sensitivity of 12 μA/mM.

This work demonstrated the preparation and characterization of a novel 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) derivative containing boronic acid group and investigation of its non-invasive/non-enzymatic fluorescence sensor behavior for determination of glucose. The novel BODIPY derivative bearing boronic acid pinacol ester (BODIPY-1) was synthesized by Sonogashira coupling reaction between Iodo-BODIPY and 4-ethynylphenylboronic acid pinacol ester. The target novel BODIPY-2 compound which was used as a fluorescence probe for the determination of glucose was synthesized from BODIPY-1by changing the pinacol ester group to the boric acid moieties. The fluorescence intensity of the BODIPY-2 fluorophore decreased when it interacted with the glucose. Sensing performance towards to glucose of this probe was evaluated in detail concerning the suitable solvent, linear concentration range, convenient pH, limit of detection (LOD), limit of quantification (LOQ) and selectivity. The LOD value of BODIPY-2 was found 0.19 mM toward glucose. Also, the complex stoichiometry between the BODIPY-2 and glucose molecules was determined by Job’s plot technique.

The Ni-metal-organic frameworks microspheres (Ni-BTC) were prepared and used directly to construct non-enzymatic glucose sensors. The Ni-BTC sensors displayed much higher glucose sensing performance than that of Ni-MOFs derived NiO, which showed wide detection regions of 5–3000$\mu$M and 3500–6000$\mu$M with the sensitivity of 932.68$\mu$A$\cdot$mM${}^{-1}\cdot$cm${}^{-2}$ and 273.04$\mu$A$\cdot$mM${}^{-1}\cdot$cm${}^{-2}$, respectively. Moreover, it also displayed good selectivity and favorable sensing feasibility for serum analysis. The high performance of the non-enzymatic glucose detection on Ni-BTC may be due to the highly efficient charge transfers during the electrocatalytic glucose oxidation process.

NiO/Pt nanotubes were obtained by firstly preparing the NiO nanotube with self-sacrificial templating methods and subsequently loading Pt nanoparticles with microwave assistant procedures. The as-prepared NiO/Pt nanotubes sensors displayed better electrocatalytic activities for glucose oxidation. The detection limit and sensitivity for glucose detection are 0.3 $\mu$M and 418.28 $\mu$A⋅ mM${}^{-1}$⋅cm${}^{-2}$ in the range of 1 $\mu$M-4000 $\mu$M. In addition, the practicality of NiO/Pt nanotubes was also confirmed by determining the glucose in serum specimen.

The development of highly sensitive, long-lasting and cost-effective dual hydrogen peroxide (H₂O${}_2)$/glucose sensors is crucial for various industries, particularly in medical, clinical diagnostics, pharmaceuticals, environmental monitoring and food business. In our study titanium dioxide/copper oxide (TiO₂/CuO) hierarchical nanostructure electrodes have been grown using hydrothermal process and their nonenzymatic H₂O₂ sensing and glucose sensing properties have been demonstrated using cyclic voltammetry and amperometry measurements. The surface morphology of TiO₂ nanorods (TiO₂ NRs) and TiO₂/CuO hierarchical nanostructure was investigated using a scanning electron microscope (SEM). The TiO₂/CuO hierarchical nanostructure electrodes demonstrated sensitivity of 20.09 $\mu$A mM${}^{-1}$ cm${}^{-2}$ toward H₂O₂, in the concentration range 0.25–18.25 mM. The TiO₂/CuO hierarchical nanostructure electrodes demonstrated a sensitivity of 1.5 mA mM${}^{-1}$ cm${}^{-2}$ towards glucose, in the concentration range 0.05–5 mM. Furthermore, artificial neural networks (ANN) were used to model the observed experimental results.