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Description
Mechanically-stimulated bioluminescence in Pyrocystis fusiformis acts as a signal for probing environmental health using time-correlated single-photon counting techniques. The York University PCS 121, a portable biosensing technique utilizing Silicon Photomultiplier (SiPM) technology, in which a mechanical stimulus triggers the bioluminescence reaction, was used to measure photon emission from the marine dinoflagellate species, P. fusiformis, under controlled excitation. This is a photon-counting instrumentation, incorporating Geiger-mode SiPM detectors and proprietary algorithm that is very sensitive in time-resolved photon count detection, with enhanced low signal-to-noise performance and integrated piezoelectric mechanical stimulation. Mechanical stimulus is applied to the species, resulting in bioluminescence.
Cultures of P. fusiformis were exposed to varying concentrations of nitrates (NaNO3; 0.883-10.9 mM) and phosphates (NaH2PO4; 36.3 μM - 3.63 mM) and prepared in a 1:1 ratio of cells + f/2 medium to chemical solution. Dose-dependent response was quantified through live cell counts and measurements of bioluminescence behaviour via photon-counting instrumentation, assessing both emission intensity and decay properties. Phosphate exposure produced measurable changes in bioluminescent properties and cell counts, indicating significant chemo-physiological response. Across the tested nitrate conditions, no significant changes in cell viability were observed, suggesting relative tolerance of P. fusiformis to nitrate-based stress within this range. This study demonstrates a reproducible approach to the biophysical assessment of environmental health as bioluminescence is coupled with photon counting techniques.
| Keyword-1 | Bioluminescence |
|---|---|
| Keyword-2 | Biophotonics |
| Keyword-3 | Photon counting |