COVID-19 electrochemical immunosensor with Ag-MOF: Rapid and high-selectivity nasal swab testing for effective detection.

Early detection of the coronavirus is acknowledged as a crucial measure to mitigate the spread of the pandemic, facilitating timely isolation of infected individuals, and disrupting the transmission chain. In this study, we leveraged the properties of synthesized Ag-MOF, including high porosity and increased flow intensity. Electrochemical techniques such as cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were employed to develop an economical and portable sensor with exceptional selectivity for COVID-19 detection. The methodology involves the deposition of Ag-MOF onto the surface of a Glassy Carbon Electrode (GCE), which resulted in a progressive augmentation of electric current. Subsequently, the targeted antibodies were applied, and relevant tests were conducted. The sensor demonstrated the capacity to detect the virus within a linear range of 100 fM to 10 nM, boasting a noteworthy Limit of Detection (LOD) of 60 fM. The entire detection process could be completed in a brief duration of 20 min, exhibiting high levels of accuracy and precision, outperforming comparable techniques in terms of speed and efficacy.

An enzyme-free Ti3C2/Ni/Sm-LDH-based screen-printed-electrode for real-time sweat detection of glucose.

Here, we report the fabrication of an enzyme-free glucose sensor benefiting from nickel-samarium nanoparticles-decorated MXene layered double hydroxide (MXene/Ni/Sm-LDH). The electrochemical response of the MXene/Ni/Sm-LDH to glucose was studied via cyclic voltammetry (CV). The fabricated electrode has high electrocatalytic activity for glucose oxidation. The voltametric response of the MXene/Ni/Sm-LDH electrode to glucose was investigated by differential pulse voltammetry (DPV) that demonstrated an extended linear range of from 0.001 to 0.1 mM and 0.25-7.5 mM with a detection limit down to 0.24 µM (S/N = 3) and a sensitivity at 1673.54 µA mM-1 cm-2 1519.09 µA mM-1 cm-2 in concentrations of 0.01 mM and 1 mM respectively as well as good repeatability, high stability and applicability for the real sample analysis. Moreover, the as-fabricated sensor was applied to glucose detection in human sweat and showed promising results.