TY - GEN

T1 - Oxygen micro-optrodes and their application in aquatic environments

AU - Klimant, Ingo

AU - Holst, Gerhard A.

AU - Kuehl, Michael

PY - 1995/12/1

Y1 - 1995/12/1

N2 - We present a new fiber-optic oxygen microsensor based on dynamic luminescence quenching which was recently developed for measuring oxygen at high spatial resolution in aquatic sediments and biofilms. Micro-optrodes with a typical tip diameter of 20 to 50 μm were fabricated. The fabrication procedure is simple and guarantees a high reproducibility of the calibration curves. The micro-optrodes were characterized with respect to dynamic range, response time, storage, longterm stability, interferences, temperature dependence, photostability, and mechanical stability. A special LED based luminescence intensity measuring instrument was developed. It is battery operated and can be used for field measurements. The micro-optrodes were used to measure oxygen gradients in marine sediments. Comparative measurements were performed with oxygen microelectrodes. The first measurements have shown that oxygen micro-optrodes present a true alternative to existing electrochemical microsensors. Nevertheless, it is obvious, that the measurement of luminescence intensity of the indicator limits their practical application. Therefore a new setup was developed to make oxygen measurements with the luminescence lifetime as parameter.

AB - We present a new fiber-optic oxygen microsensor based on dynamic luminescence quenching which was recently developed for measuring oxygen at high spatial resolution in aquatic sediments and biofilms. Micro-optrodes with a typical tip diameter of 20 to 50 μm were fabricated. The fabrication procedure is simple and guarantees a high reproducibility of the calibration curves. The micro-optrodes were characterized with respect to dynamic range, response time, storage, longterm stability, interferences, temperature dependence, photostability, and mechanical stability. A special LED based luminescence intensity measuring instrument was developed. It is battery operated and can be used for field measurements. The micro-optrodes were used to measure oxygen gradients in marine sediments. Comparative measurements were performed with oxygen microelectrodes. The first measurements have shown that oxygen micro-optrodes present a true alternative to existing electrochemical microsensors. Nevertheless, it is obvious, that the measurement of luminescence intensity of the indicator limits their practical application. Therefore a new setup was developed to make oxygen measurements with the luminescence lifetime as parameter.

UR - http://www.scopus.com/inward/record.url?scp=0029511030&partnerID=8YFLogxK

M3 - Article in proceedings

AN - SCOPUS:0029511030

SN - 0819418668

SN - 9780819418661

VL - 2508

SP - 375

EP - 386

BT - Proceedings of SPIE - The International Society for Optical Engineering

T2 - Chemical, Biochemical, and Environmental Fiber Sensors VII

Y2 - 19 June 1995 through 20 June 1995

ER -