Abstract
We present a new method for quantifying spatio-temporal O 2 distribution and dynamics at biologically active surfaces with a complex surface topography. Magnetized O 2 optode microparticles (~80-100 μm) containing the NIR-emitting luminophore platinum (II) meso-tetra(4-fluorophenyl) tetrabenzoporphyrin (PtTPTBPF; ex. max. 615 nm; em. max. 780 nm) were distributed across the surface tissue of the scleractinian coral Caulastrea furcata and were held in place with a strong magnet. The O 2-dependent luminescence of the particles was mapped with a lifetime imaging system enabling measurements of the lateral surface heterogeneity of the O 2 microenvironment across coral polyps exposed to flow. Mapping steady-state O 2 concentrations under constant light and O 2 dynamics during experimental light-dark shifts enabled us to identify zones of different photosynthetic activities within a single coral polyp linked to the distribution of coral host pigments. Measurements under increasing irradiance showed typical saturation curves of O 2 concentration and estimates of gross photosynthesis that could be spatially resolved at ~100 μm pixel resolution. The new method for O 2 imaging with magnetized optode particles has much potential to be used in studies of the surface microenvironment of other aquatic systems such as sediments, biofilms, plant, and animal tissue.
| Original language | English |
|---|---|
| Journal | Marine Biology |
| Volume | 159 |
| Issue number | 7 |
| Pages (from-to) | 1621-1631 |
| Number of pages | 11 |
| ISSN | 0025-3162 |
| DOIs | |
| Publication status | Published - Jul 2012 |