Zhizhen Wu

Lead (Pb) has long been acknowledged as a systemic toxicant, with pronounced health impacts observed even at low exposure levels, particularly in children. Adverse effects include diminished cognitive function, altered behavior, and developmental delays. Consequently, it is imperative to conduct regular monitoring of Blood Lead Levels (BLLs). In this work, we report on an electrochemical sensor based on screen-printed carbon electrode (SPCE) coated with Nafion and mesoporous carbon (MC). The sensor system uses simple sample preparation (acidification and dilution of whole blood), minimal sample volume (a few blood drops, 200 μl), and swift time-to-results (1 h). A limit of quantitation (LOQ) of 0.3 μg dL⁻¹ Pb was achieved in whole blood. To demonstrate the practical utility of our sensor system, we evaluated its performance in the analysis of blood samples collected from children (n = 25). Comparative analysis with the laboratory-based gold standard method of inductively coupled plasma mass spectrometry (ICP-MS) demonstrated approximately 77% accuracy and 94% precision. We anticipate that our approach will serve as a valuable tool for more frequent BLL monitoring, particularly in communities where access to laboratory testing is impractical or expensive.

Flexible pressure and thermal sensors are the critical parts of the functional electronic skin of prostheses and robots, as well as flexible catheter/devices for multimodal biomedical monitoring. In this paper, a polysilicon thin film was developed on a flexible polyimide substrate using aluminum induced crystallization process for biomedical pressure and temperature sensing applications. The formation of polycrystalline structure was verified from the developed polysilicon film. Long term stability and real-time temperature tests were performed to evaluate potential application to the in vivo monitoring of brain or body temperature. The linear real-time change of polysilicon resistance with temperature was attained with the temperature coefficient of the resistance of −0.0027/°C and the resolution of 0.05 °C. With a gauge factor of 10.3, the polysilicon film developed in this paper represents a promising material for the development of high-sensitivity pressure sensors on flexible polyimide substrates. [2015-0106]