MEASUREMENT OF NITROUS OXIDE IN A NITROGEN MATRIX USING GAS CHROMATOGRAPHY WITH MICROELECTRON CAPTURE DETECTION: VALIDATION OF ANALYTICAL METHOD

Abstract

Atmospheric nitrous oxide (N2O) as one of the most potent greenhouse gases significantly contributes to the global warming effect. Therefore, an accurate and valid measurement method for monitoring its environmental release is of great importance. In this study, an analytical method for the measurement of N2O in a nitrogen (N2) matrix using gas chromatography and microelectron capture detection (GC??ECD) has been validated. The analytical method was validated in terms of some performance parameters such as system suitability, precision (repeatability and reproducibility), linearity, limit of detection (LoD) and limit of quantitation (LoQ), accuracy and method robustness. The results show that the GC system was found to be suitable for the measurement of N2O in the N2 matrix. The repeatability and reproducibility of the method were found to have %RSD of 1.42 and 0.71, respectively, indicating that the method is repeatable and reproducible for N2O measurement. The linearity of the method was excellent, having the R2 value of 0.9998. The LoD and LoQ of the method were found to be 0.10 and 0.34 µmol mol-1, respectively. Evaluation of method accuracy showed that the method is also accurate for the measurement of N2O in the N2 matrix. The method’s roughness indicated that the method was quite stable and unaffected by slight changes in the experimental conditions. From this study, it can be concluded that the validated method can be used in testing laboratory for internal quality assurance programs purposes related to the measurement of N2O in N2 matrix.