Precision engineering of surface defects of cerium oxide nanostructured fine particles for the multiplexed detection of electrolytes and glucose inside tissue models

• Published in: Applied materials today 2024-12, Vol.41, p.102435, Article 102435
• Main Authors: Ruiz-Gonzalez, Antonio, Xun, Cao, Yizhong, Huang, Choy, Kwang Leong
• Format: Article
• Language: English
• Subjects: Biosensor; Cerium oxide; Electrochemical sensor; Glucose sensor; Ion sensor
• ISSN: 2352-9407
• DOI: 10.1016/j.apmt.2024.102435

•The doping of cerium oxide nanoparticles with nickel has an impact on sensing performance of glucose sensors.•Low levels of nickel doping in cerium oxide nanoparticles enhance the sensitivity, selectivity, and long-term stability.•Cerium oxide can be incorporated inside an ion sensor structure to allow the multiplexed sensing of glucose and ions.•Pulse voltammetry enhance the sensitivity and allow a non-invasive assessment of both glucose and sodium in the skin.•Skin models based on porous organosilicon/hydrogel hybrid materials can successfully implemented for the testing of devices. The development of biosensors for the detection of glucose and electrolytes has become a crucial field of research nowadays due to the increasing incidence of long-term conditions. Specifically, the use of cerium oxide as a selective material for the detection of glucose is raising interest as an alternative to enzymatic sensors due to their stability and low-cost. This work demonstrates for the first time a significant improvement in the selectivity of glucose sensors based on cerium oxide nanostructured fine particles through doping with nickel ions and using pulse voltammetry for the sensing. By using nickel-doped cerium oxide fine particles, the sensitivity of the devices improved by 10-fold, and the selectivity when testing the devices against lactate increased by 68.5 % as compared to pure cerium oxide fine particles, with a limit of detection in the micromolar level. Crystallographic and compositional properties that led to such increase in sensitivity were determined, as a result of a presence of oxygen defects and amorphous domains at the surface of fine particles. This device could be adapted for the simultaneous measurement of glucose and sodium ions. The pulse voltametric approach enhanced the sensitivity of the sensors towards sodium ions, which reached a super-Nernstian sensitivity of 111 mV Log[Na+]-1, with a response time of 2 mins, and has been used for the testing of the electrodes in a practical environment using a skin-inspired material. This technology will pave the way for the development of miniaturised non-invasive wearable sensors real-time measurement of glucose and electrolytes in patients. [Display omitted]