Mainz 2017 – scientific programme
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MO: Fachverband Molekülphysik
MO 17: Experimental Techniques
MO 17.4: Talk
Friday, March 10, 2017, 12:00–12:15, N 6
Development of Cavity Ring-Down Spectroscopy for Carbon Isotope Analysis of Biomedical Samples — •Volker Sonnenschein1, Ryohei Terabayashi1, Hideki Tomita1, Noriyoshi Hayashi1, Shusuke Kato1, Lei Jin1, Masahito Yamanaka1, Norihiko Nishizawa1, Atsushi Sato2, Kohei Nozawa2, Kenta Hashizume2, Toshinari Oh-hara2, and Tetsuo Iguchi1 — 1Graduate School of Quantum Engineering, Dep. of Engineering, Nagoya University, Nagoya, Japan. — 2ADME and Tox. Research Institute, Sekisui Medical, Tokai, Ibaraki, Japan
High sensitivity techniques such as Accelerator Mass spectrometry are commonly used for detection of the radioisotope 14C. In the environment, its abundance is typically at the ppt level, however in medical samples, where it is used as tracer isotope to study the metabolism of subjects or other biological processes, the abundance can be significantly higher. Detection may then be performed by application of optical methods such as Cavity Ring-Down Spectroscopy (CRDS), thus providing a more compact and inexpensive solution as well as possibilities for in-field measurements.
An overview and status of our current system for CRDS of 14CO2 in the Mid-IR wavelength range will be given. The optical cavity is directly coupled to a CHNS elemental analyzer, allowing quick sample analysis. Thermo-electric cooling is applied to suppress interference by absorption of other close-lying molecular transitions. Remaining contaminants in biomedical samples are analyzed and the sensitivity and linearity of the 14C determination are estimated.