Cu-MOF derived CuO nanoparticle decorated amorphous carbon as an electrochemical platform for the sensing of caffeine in real samples

• Published in: Journal of the Taiwan Institute of Chemical Engineers 2022-04, Vol.133, p.104248, Article 104248
• Main Authors: Saravanakumar, Veeramuthu, Rajagopal, Venkatachalam, Kathiresan, Murugavel, Suryanarayanan, Vembu, Anandan, Sambandam, Ho, Kuo-Chuan
• Format: Article
• Language: English
• Subjects: Amperometry; Caffeine; Carbonization; Electrochemical sensor; Metal organic framework
• ISSN: 1876-1070; 1876-1089
• DOI: 10.1016/j.jtice.2022.104248

•CBT-MOF and its carbon nanocomposites were synthesized and characterised.•Catalytic effect of GC modified electrode on the oxidation of caffeine was studied.•The sensor shows wide linearity with good repeatability and reproducibility.•The material could detect caffeine as low as 19 nM.•The electrode was employed for the detection of caffeine from coffee samples. Background: In recent times, development of an efficient electrode material for the determination of caffeine content in beverages and other related sources becomes essential. In this work, for the first time, a novel electrochemical sensor based on carbonized Cu-4,4’-bipyridine-trimesic interlinked metal-organic framework (CBT-MOF) was prepared, characterized by various surface analytical techniques and employed for the effective sensing of caffeine. Method: Copper-4,4’-bipyridine-trimesic acid interlinked MOF (CBT-MOF) was prepared by simple solvo-thermal method and it was carbonized at different temperatures. Significant findings The superiority of CBT-500 may be associated with rise in the Conductivity of the copper oxide nanoparticles by increasing the carbonizing temperature at 500 °C. which enhances the electron transfer kinetics between the analyte and the copper oxide nanoparticle. Increase in temperature above 500 °C, (CBT-600 and CBT-700), results in lower conductivity, thereby decreasing the electron transfer kinetics between the electrode/electrolyte interface. As expected, the amperometric detection of caffeine on fabricated electrode material provided a linear dynamic range from 1 to 10 μM with a low detection limit and higher sensitivity of 0.0190 μM and 0.0848 mA μM−1 cm−2. Further, the fabricated electrode material remained stable, leading to a promising sensor material for the analysis of caffeine in coffee samples. [Display omitted]