title: Poly(methyltetradecylsiloxane) immobilized onto silica for extraction of multiclass pesticides from surface waters.
abstract: A new material based on poly(methyltetradecylsiloxane) (PMTDS) thermally immobilized onto a silica support has been tested as a sorbent for the solid-phase extraction (SPE) from water of several pesticides used in soybean cultivation. The SPE methodology was developed and validated for six of these pesticides (imazethapyr, imazaquin, metsulfuron-methyl, bentazone, chlorimuron-ethyl and tebuconazole) according to the International Conference on Harmonization directives and the results were compared with those obtained with a commercial C18 SPE cartridge. The PMTDS-based sorbent gives results similar to the commercial sorbent with recoveries and precisions in agreement with directives for residue analysis. The quantification limits, after concentration, of all the pesticides evaluated were 1.0 microg L(-1), below the levels imposed by the principal regulatory agencies. The PMTDS-based sorbent preparation is fast, easy and reproducible and the cartridges are less expensive than similar commercial SPE materials.
authors: Instituto de Química, Universidade Estadual de Campinas, Cx. Postal 6154, 13084-971 Campinas, SP, Brazil.
authors: Anizio M
authors: AM
authors: Faria
authors: Liane
authors: L
authors: Maldaner
authors: César C
authors: CC
authors: Santana
authors: Isabel C S F
authors: IC
authors: Jardim
authors: Carol H
authors: CH
authors: Collins
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D010573:Pesticide Residues / Q000145:classification / Q000302:isolation & purification*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry*; D012833:Siloxanes / Q000737:chemistry*; D013057:Spectrum Analysis; D014874:Water Pollutants, Chemical / Q000145:classification / Q000302:isolation & purification*
chemical_list: D010573:Pesticide Residues; D012833:Siloxanes; D014874:Water Pollutants, Chemical; C513729:poly(methyltetradecylsiloxane); D012822:Silicon Dioxide