LIMIT OF DETECTION OF C-13 USING AN ATOMIC-EMISSION DETECTOR (MIP) COUPLED TO GAS-CHROMATOGRAPHY

This paper presents the capability of using molecules labelled with C-13 and of measuring them by gas chromatography coupled to an MIP. The sensitivity of the detection of this stable carbon isotope has been optimised using non steroid anti inflammatory drugs such as Fenoprofen, Flurbiprofen, Ketoprofen and Diclofenac and applying a four factors experimental design. This work shows that the main factors acting on the sensitivity of the C-13 detection are the flow rates of hydrogen and helium (plasma gas). The linearity was demonstrated in the range from 50 to 300 pg of C-13. The limit of detection calculated according to various methods (IUPAC, Oppenheimer and Quimby - Sullivan) gave the following results: 2 pg/mu l, 12 pg/mu l and 0.1 pg/s respectively. These results show that C-13 atomic emission is quite a specific and sensitive mode of detection of C-13 labelled molecules after gas chromatographic separation.