(276c) Diagnostic Sodium Ion Sensor for the Real-Time Screening and Diagnosis of Cystic Fibrosis
We present the conception of a single atomic layer of carbon - functionalized electrochemical sodium ion sensor for the real-time screening and early diagnosis of cystic fibrosis (CF), a genetic disease that attacks the lungs, pancreas, liver, and intestines. CF is characterized by the abnormal transport of sodium and chloride ions across the epithelium and is therefore most commonly diagnosed by sweat testing. In this work, a flexible electronic sensor has been developed to quantify the amount of sodium ions in sweat (in real-time), alleviating the wait time, large sample size, possible contamination, and analytical equipment currently associated with sweat testing. This sensor is composed of a multi-wall carbon nanotube (MWCNT) or graphene coated Nylon-6 mat, for a flexible yet conductive sensor. The atomic layer of carbon is then functionalized with a cyclo-oligomeric calixarene, which has been shown to selectively form a supramolecular complex with sodium ions. Upon complex formation with the sodium analyte, the charge carriers are drawn away from the carbon layer, hence the current is impeded, and the sodium ion detection is prevalent at levels appropriate for accurate diagnosis of CF. In this presentation, the optimization of carbon- and calixarene- functionalization, nylon conditions, as well as the selectivity and sensitivity of the sensor will be discussed.