Wang et al. developed a novel sensor system by electrochemical oxidation of the mixture of PD173074 L cysteine and CNTs at GCE for the determination of terbinafine in human serum. A composite film, found on GCE after oxidation, was responsible for the significant increase in the current response of terbinafine. It showed a wide range of linear response, 80 nM 50 M, with the detection limit of 25 nM for terbinafine determination. Zhu et al. prepared CNTs ceramic composites electrode for electrochemical sensing by dispersing MWCNTs into the methyltrimethoxysilane derived sol gel solution. The electrode provided a better reversible behavior with a substantial decrease of overpotential, and a higher sensitivity compared to the unmodified one towards the electrochemical detection of ascorbic acid, uric acid, acetaminophenol, NADH, EP, DA, cysteine, and H2O2.
Wang and coworkers . This electrode showed an electrocatalytic Vismodegib activity towards insulin and exhibited a wide range of linear response of 10 800 nM with a detection limit of 1 nM. Recently, Snider et al. developed a MWCNTs/dihydropyran composite film for the electrochemical detection of insulin secreted by islets in a microfluidic system. Vega et al. developed a tetracycline antibiotic sensor based on MWCNTs modification of GCE. A highly sensitive and reproducible electroanalytical response of tetracycline was attributed to the antifouling capability of the MWCNTs. Rezaei and Zare described a simple and highly sensitive method based on the modification of GCE by MWCNTs for the direct voltammetric determination of noscapine in pharmaceutical and clinical samples.
It significantly enhanced the noscapine signal and showed a wide linear range of 0.4 M 10 mM, under the optimum condition, with the detection limit of 80 nM. They also applied the same electrode to study the determination of captopril with effective electrocatalysts, hexacyanoferrate. The system of MWCNTs and hexacyanoferrate strongly enhances the oxidation of captopril and a detection limit of 0.2 M was obtained. Buratti et al. introduced cobalt oxide with the MWCNTs modified GCE for the detection of carbohydrates and thiols. The modified electrode showed excellent electrocatalytic activity towards the oxidation of carbohydrates and thiols. 4.
Carbon Nanotube Based Electrochemical Biosensors An electrochemical biosensor is an analytical tool for sensitive and selective detection of biomolecules. Increasing attention has been given to biosensors due to their potential applications in clinical chemistry, food industry, and environmental fields. Glucose oxidase based glucose biosensors are still considered as a primary model system in the development of new sensing materials and methods. They are the most extensively studied enzyme biosensors because of their high demand for blood glucose monitoring. A summary of recent progress in the field of glucose biosensors can be found in two excellent recent reviews by Wang and Heller. CNTs are extremely attractive for fabricating electrochemical biosensors due to their outstanding properties, especially the excellent conductive, adsorptive and biocompatibility.