A new strategy for the chemiluminescent screening analysis of total N-methylcarbamate content in water

A new procedure for the screening of total N-methylcarbamate (NMCs) content in water at different concentration levels is here presented. It is based on a previous off-line alkaline hydrolysis of the NMCs, for the production of methylamine (MA), and its subsequent derivatisation with o-phthalaldehyde (OPA). After that, the obtained derivative is involved in the peroxyoxalate chemiluminescent (PO-CL) reaction using imidazole as a catalyst being the CL emission proportional to the total NMC content. The chemiluminescent reaction is carried out in a flow injection analysis (FIA) manifold, employing sodium dodecyl sulphate micellar medium as carrier, which avoids the rapid degradation of POs in water solution. The applicability of the screening method is shown for the monitoring of NMCs in natural waters. Analytical features, as specification limit signal, screening uncertainty, sensitivity and specificity, are calculated.