Study of the Effect of Air to Fuel ratio Parameter on the Organophosphorus – Pesticide Analysis by GC-FPD

In the present contribution, sensitive and precise method for the quantification of Organophosphorus / Pesticides (Malathion and Dimethoate) in nanograms range has been developed. The performance of flame photometric detector (FPD), a selective detector (P&S-mode) that can be used in the analysis of organophosphorus compound, is evaluated in terms of sensitivity, selectivity and reproducibility. The performance of flame photometric detector was strongly depending on the absolute and relative flow rate of air and hydrogen gases. The optimum air-to-fuel ratio for detection of Malathion and Dimethoate was 0.4 and 0.3 (FPD-P mode). At this ratio, low picogram amounts of phosphor can be detected accurately (0.18 pgP) with a wide linear dynamic range of 0.18 pgP to 298 ngP. While, the optimum air-to-fuel ratio, for detection of Malathion and Dimethoate was 0.6 (FPD-S mode). In addition to, the method is precise with 4.5 % relative standard deviation (RSD). In conclusion, it could be proposed that this procedure can be recommended as a suitable method for the quantification of Malathion and Dimethoate in cases of acute poisoning.