Coordination polymer adsorbent for matrix solid-phase dispersion extraction of pesticides during analysis of dehydrated Hyptis pectinata medicinal plant by GC/MS

The coordination polymer [Zn(BDC)(H2O)(2)](n) was tested for extraction of pyrimethanil, ametryn, dichlofluanid, tetraconazole, flumetralin, kresoxim-methyl and tebuconazole from the medicinal plant Hyptis pectinata, with analysis using gas chromatography-mass spectrometry in selected ion monitoring mode (GC/MS, SIM). Experiments carried out at different fortification levels (0.1, 0.5 and 1.0 mu g g(-1)) resulted in recoveries in the range 73-97%, and RSD values were between 5 and 12% for the [Zn(BDC)(H2O)(2)](n) sorbent. Detection and quantification limits ranged from 0.02 to 0.07 mu g g(-1) and from 0.05 to 0.1 mu g g(-1), respectively, for the different pesticides studied. The method developed was linear over the range tested (0.04-14.0 mu g g(-1)), with correlation coefficients ranging from 0.9987 to 0.9998. Comparison between [Zn(BDC)(H2O)(2)](n) and the commercial phase C-18-bonded silica showed good performance of the [Zn(BDC)(H2O)(2)](n) polymeric sorbent for the pesticides tested. (C) 2010 Elsevier B.V. All rights reserved.