Basic NeuroscienceFRET excited ratiometric oxygen sensing in living tissue

Dynamic analysis of oxygen (O2) has been limited by the lack of a real-time, quantitative, and biocompatible sensor. To address these demands, we designed a ratiometric optode matrix consisting of the phosphorescence quenching dye platinum (II) octaethylporphine ketone (PtOEPK) and nanocystal quantum dots (NQDs), which when embedded within an inert polymer matrix allows long-term pre-designed excitation through fluorescence resonance energy transfer (FRET). Depositing this matrix on various glass substrates allowed the development of a series of optical sensors able to measure interstitial oxygen concentration [O2] with several hundred millisecond temporal resolution in varying biological microdomains of active brain tissue.

► We report how to fabricate a series of FRET based optical oxygen sensors. ► FRET sensing can monitor extracellular oxygen dynamics in living tissue. ► Seizure events are associated with layer specific O2 changes in the hippocampus.