APPLICATION OF LASER-INDUCED PHOTOACOUSTIC-SPECTROSCOPY TO THE DETERMINATION OF TC-99

Laser induced photoacoustic spectroscopy was applied to the determinat ion of Tc-99 in a solution coupled with quantitative complexation of T c with tu (thiourea) to form Tc(tu)6(3+). The complexation procedure w as adopted to shift the uv absorption peak of pertechnetate to the vis ible region. Photoacoustic signals due to the 488 nm absorption peak o f Tc(tu)6(3+) was analyzed by using a Fast Fourrier Transform (FFT) sy stem. The quantitative detection of Tc could be easily performed down to the 10(-8) M concentration in this system. This is about 1,000 time s more sensitive than the ordinary colorimetric measurement.