부산대학교 도서관

Cystic Fibrosis (CF) is a genetic disease which affects the production of healthy cystic fibrosis transmembrane regulator (CFTR) proteins. These facilitate the transport of various salts across epithelial membranes throughout the body and their dysfunction leads to the development of life-limiting conditions across multiple organs. One consequence of CFTR dysfunction is that CF sufferers possess elevated levels of chloride (Cl-) ions in their sweat. CF treatments which target the CFTR proteins to improve their functionality are increasingly being developed and becoming more widely available. Sweat Cl- concentration is an important biomarker to gauge their efficacy. A wearable sensor capable of detecting Cl- in aqueous media would allow sweat Cl- levels to be monitored quickly and non-invasively and be a vital tool in the development of future CF therapies. This work describes the development of a Cl- ion selective electrode. It adapts existing wearable electrode technology through the addition of a UV-cured pHEMA hydrogel mixture to form a quasi-reference electrode. Laboratory tests found that conditioning the hydrogel in a 1 M KCl solution for 25 hours produced electrodes with consistent potentiometric responses to test solutions, enabling a calibration curve to be obtained with a sensitivity of 64.34 mV/dec over a Cl- concentration range of 10 - 100 mM. This envelops both healthy and CF sweat Cl- levels. A study was conducted to examine the pHEMA electrodes' ability to operate whilst placed on the forearms of healthy volunteers. Whilst these tests highlighted some of the challenges faced by wearable devices, such as motion artefacts, five of the ten tests carried out demonstrated that the electrodes were capable of monitoring Cl- concentration whilst placed on the body. They displayed a high degree of sensitivity which compared well to the lab bench tests conducted in parallel.