Integration of an Emerging Highly Sensitive Optical CO2 Sensor for Ocean Monitoring on an Existing Data Acquisition System SeaKeeper 1000 (trademark)
Annual rept. 1 Oct 2011-30 Sep 2012
MARYLAND UNIV BALTIMORE COUNTY BALTIMORE MD DEPT OF CHEMICAL AND BIOCHEMICAL ENGINEERING
Pagination or Media Count:
The novelly designed optical sensor for autonomous ocean monitoring works on equilibrium principles. When the pH-sensitive reagent solution sitting behind a gas-permeable membrane is exposed to seawater, the CO2 molecules present in the seawater diffuse across the membrane into the reagent and induce a pH change. After equilibrium is reached, the fluorescence is measured and the pCO2 data are recovered from a calibration curve. A specific feature of our measurement technique is the use of excitation ratiometric approach. A violet LED Light Emitting Diode and a blue LED are used to excite the sensing reagent through an excitation filter and the pCO2 dependent emission is measured through an emission filter by a photodiode.
- Physical and Dynamic Oceanography