engleski

Solid-phase extraction with styrene-divinylbenzene sorbent for high performance liquid or gas chromatographic determination of urinary chloro- and methylthiotriazines

Solid-phase extraction (SPE) procedure on styrene-divinylbenzene (SDB-1 cartridge) for extraction and cleaning of triazine herbicides atrazine, simazine, ametryn, and prometryn and atrazine monodealkylated metabolites from urine samples was developed and optimised for final high-performance liquid chromatographic (HPLC-UV DAD) and gas chromatographic (GC-ECD and GC-TSD) analysis. Interfering polar matrices were eliminated by rinsing SDB-1 with 1% acetonitrile in water or with pure water. Extraction recoveries were from 78 to 101 % with RSD about 10% for all studied compounds. Extraction recovery for didealkylated atrazine metabolite was significantly lower and this compound can not be determined with these procedures. Sorbent matrix generated interferences, although not detected by the chromatographic system, lowered the response of nitrogen-phosphorus and electron capture GC detectors for monodealkylated chlorotriazines when compared to standards prepared in n-hexane. The HPLC and GC analysis with SPE (SDB-1) preconcentration showed excellent linearity over the concentration range tested, with detection limits in urine of 10 ng/ml for parent herbicides (HPLC and GC analysis) and 20 ng/ml of monodealkylated chlorotriazines (HPLC analysis).

urine; atrazine; simazine; ametryn; prometryn; atrazine metabolites; GC analysis; HPLC analysis

nije evidentirano