Imaging of surface O₂ dynamics in corals with magnetic micro optode particles

TY - JOUR

T1 - Imaging of surface O2 dynamics in corals with magnetic micro optode particles

AU - Fabricius-Dyg, Jon

AU - Mistlberger, G.

AU - Staal, Marc Jaap

AU - Borisov, S.M.

AU - Klimant, I.

AU - Kühl, Michael

PY - 2012/7

Y1 - 2012/7

N2 - 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.

AB - 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.

U2 - 10.1007/s00227-012-1920-y

DO - 10.1007/s00227-012-1920-y

M3 - Journal article

SN - 0025-3162

VL - 159

SP - 1621

EP - 1631

JO - Marine Biology

JF - Marine Biology

IS - 7

ER -