(229ay) Extending the Dynamic Range of Nanosensors

Recent years have shown the incredible versatility and utility of polymeric optode-based nanosensors. Sensors have been developed for a wide variety of ionic analytes (e.g. sodium, potassium, pH) as well as nonionic analytics (e.g. glucose) and have been applied for challenging research fields such as detection of sodium sparks in live cardiomyocytes. This field of research has yielded new knowledge on cellular metabolism and function. Additionally, these sensors can be applied in vivo, through implantation in or under the skin in animals; showing potential as a research tool for continuous monitoring of analyte concentrations without the need for direct samples to be taken from the animal.

However, one of the key limitations of these sensors is the dynamic range is often limited relative to the desired range for physiological application. There are two key causes for this limitation: the optode mechanism and the available selection of chromoionophores. Relative to a similar technology, ion-selective electrodes, the pH based mechanism inherently limits dynamic range based on the pKa of the chromoionophore. In this work we control the dynamic range of these nanosensors through altering the formulation of the optode components. This results in nanosensors with tunable and extended dynamic ranges â?? a necessary step in measurement cases where concentrations change by more than one order of magnitude.