TiO2 NPs@UiO-66 TiZr dual active centers demonstrate excellent performance in phosphoprotein detection in sweat

Protein phosphorylation in sweat metabolites plays a key role in nerve activity, muscle contraction, and other activities, and abnormal protein phosphorylation may lead to diseases such as neurodegenerative disorders. Real-time non-invasive monitoring of changes in phosphorylated protein levels in sweat facilitates the development of prevention of human degenerative neurological diseases. Here, an electrochemical sensor for the detection of trace phosphoproteins in sweat was constructed by exploiting the selective enrichment ability of the TiZr dual active center in the TiO₂ NPs@UiO-66 structure for phosphoproteins. The common phosphoprotein α-Casein was selected as a demonstration sample to show the functionality of the designed sensing platform. The sensor exhibited excellent selectivity, repeatability, reproducibility and stability with a detection limit as low as 0.659 μmol/L and a detection range of 1–10 μmol/L. In addition, the low biotoxicity of the prepared materials was verified by biological experiments on SD rats and volunteers, which can meet the needs of skin-friendly biosensors. The detection of phosphoproteins in human sweat at rest and during exercise verified the performance for practical applications. This work realizes the goal of non-invasive and continuous detection of phosphoproteins in sweat in wearable devices.