engleski

Development of novel chemical sensors for emerging mobile wireless applications

A key challenge in the development of chemical sensors for wireless mobile applications is designing novel sensors that meet the analytical performance requirements of the target application. The sensor chemistry must be designed and optimised to work within the limits imposed by the wireless platform. In this thesis, the analytical performance of a radio-frequency identification (RFID) wireless sensor platform, which was designed specifically for integration with (bio)chemical sensors, has been evaluated through model experiments with well characterised chemical sensors, in three transduction modes. The potentiometric mode has been evaluated by determining pH with a glass electrode, amperometric by determining the concentration of K3Fe(CN)6 with a gold disk electrode and glucose with commercial glucose test strips, and optical by determining concentration of a dye in solution and K+ concentration with ion-selective optode membranes. Additionally, pH sensitive hybrid inorganic- organic sol-gel thin films, intended for integration with the optical RFID platform have been developed and characterised. The films were fabricated by immobilising bromocresol green, a pH indicator, in different sol-gel matrices. Characterisation of the films gave insight into correlation of film surface properties with pH sensing characteristics, both of which are important in different wireless chemical sensor applications. A wireless smart bandage biosensor for uric acid, an important and specific biomarker of wound status, has been developed. The system was developed by integrating a novel amperometric bandage-based screen-printed sensor with an amperometric RFID platform. Immobilised urate oxidase, paired with a printed catalytic Prussian blue transducer, facilitates chronoamperometric detection of uric acid at a low working potential. The analytical performance of the smart bandage – sensitivity, selectivity, operational stability and mechanical robustness – has been determined. It is expected that novel sensing systems such as the ones developed in this research will enable many mobile chemical sensor applications, and will underpin the realisation of the Internet of Things in the emerging connected world.

wireless chemical sensor; wearable sensor; optical pH sensors; sol-gel thin films; smart bandage; radio-frequency identification; Internet of Things

nije evidentirano