Paper BI+AS+IPF+NS-TuA2
Organosilica pH Nanosensors Applied to Realtime Metabolite Monitoring

Tuesday, October 23, 2018, 2:40 pm, Room 101B

Continuous monitoring of biomarkers in biological environments is a key challenge for the development of biosensors capable of providing real-time feedback¹. These sensors promise to aid in the treatment of diseases with a highly dynamic nature however current technologies remain scarce¹. Nanoparticle based “optodes” have emerged as sensitive and tuneable biosensors, using chromo/ionophores to generate analyte-specific changes in fluorescence spectra in a dynamic and reversible manner. Currently this type of sensor suffers from limitations including leaching of reagents from the nanoparticles over time, combined with poor colloidal stability and resistance to fouling in biological fluids.

An organosilica core-shell pH sensitive nanoparticle containing a mixture of covalently incorporated pH-sensitive (shell) and pH-insensitive (core) fluorescent dyes has been developed. This platform demonstrates good long term stability (80 days), fast response time (<100 ms) and resistance to fouling in biological conditions². This presentation will describe the modification of these pH sensing particles towards the production of a lactate responsive particle for sensing through coupling with lactate dehydrogenase. Here we will present our latest results focussed on enzyme encapsulation in addition to modulation of shell parameters including thickness and degree of crosslinking in order to tune response kinetics for application in biological tissues.

¹ Corrie, S. R. et al., Analyst, 2015, 140, 4350-4364

² Robinson, K. J. et al., ACS Sensors, 2018