Wearable multi-sensing platform for ion-sensing
Motivation:
Precise and quantitative measurements of ions in solution are crucial in several different applications, including medical analysis, water and environmental monitoring, agriculture and industrial processes control. Solid-Contact Ion-Selective Electrodes have attracted considerable attention in recent years to build portable and miniaturized ion-sensors with integrated read-out electronics. These systems are especially important in healthcare monitoring to develop next-generation wearable smart devices. Although several improvements have been made thanks to the investigation of new solid-contact materials and to the better understanding of transport phenomena in the membranes, some major issues like need of calibration, limited selectivity and potential drift still need to be solved.
Goal:
The project aims at the fabrication of a general-purpose portable multi-sensing platform for ion-sensing for different healthcare purposes. Sweat will be used as main sample fluid because it represents a promising substitute to blood thanks to the simple artificial reproducibility and to the large accessibility that does not require invasive or painful procedures. Its diagnostic potential has already been demonstrated in several research works for different applications. Some commercial examples are also available nowadays. The device will be realised on a flexible headband to ensure conformability and direct sweat uptake. The platform will also be implemented in a rigid format. The design will include a temperature sensor and sensing sites for different target ions for different applications including Therapeutic Drug Monitoring (TDM), toxicology, exercise and healthcare monitoring.
Highlights:
The stability of the potential response is significantly improved with the use of nanostructured gold and platinum contacts. Furthermore, the sensors show good reversibility. The developed technology is used to sense different ions in water and in artificial sweat. The microfabricated ion-selective electrodes offer Nernstian behaviour with short response time (∼15 s) and small potential drift. High selectivity values and low Limit Of Detection (LOD) are obtained, with values comparable to the ones reported for conventional systems.
A complete list of publications can be found here.
References:
- F. Criscuolo; I. Taurino; F. Stradolini; S. Carrara; G. De Micheli : Highly-stable Li + ion-selective electrodes based on noble metal nanostructured layers as solid-contacts; Analytica Chimica Acta. 2018-10-16. DOI : 10.1016/j.aca.2018.04.062.
- F. Criscuolo; I. Taurino; S. Carrara; G. De Micheli : A novel electrochemical sensor for non-invasive monitoring of lithium levels in mood disorders. 2018-07-21. 40th International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), Honolulu, Hawaii, USA, July 17-21, 2018.
- Hu et al., Rational design of all-solid-state ion-selective electrodes and reference electrodes, Trends Anal. Chem. 76 (2016) 102-114
- I. Taurino et al., Fast synthesis of platinum nanopetals and nanospheres for highly-sensitive non-enzymatic detection of glucose and selective sensing of ions, Sci. Rep. 5 (2015) 1-10