1,3,5-Triazine functionalized chitosan encapsulated nanocomposite for electrochemical dual detection of glucose and...

A new electrochemical sensor was designed based on a silver/iron oxide (AgFe₂O_3)-incorporated functionalized chitosan (AgFe₂O₃/FCS) nanocomposite for the detection of glucose and hydrogen peroxide (H₂O₂). The AgFe₂O₃/FCS nanocomposite was synthesized via an ultrasonic method followed by a hydrothermal technique. Its structure, chemical composition, and morphology were analyzed using several techniques, such as X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (HR-TEM), and electrochemical impedance spectroscopy (EIS). The synthesized AgFe₂O₃/FCS nanocomposite exhibited a significantly increased electrochemically active surface area (0.162 cm²), contributing to its enhanced electrochemical sensitivity for glucose and H₂O₂ detection. The sensor displayed wide dynamic ranges of 1-5847 μM for glucose and 1-6848 μM for H₂O₂, with sensitivities of 18.33 μA μM^-1 cm^-2 and 20.65 μA μM^-1 cm^-2, respectively. The detection limits were 0.17 μM for glucose and 1.48 μM for H₂O₂, with response times of 5 s and 3 s, respectively. In addition to good selectivity, stability, and reproducibility, the sensor successfully detected glucose in serum samples and H₂O₂ in live human cervical cancer (HeLa) cells. This nanocomposite has great potential as an attractive sensing platform for the electrochemical detection of glucose and H₂O₂.