title: Study of nitrophenols preconcentration using quinolin-8-ol immobilized on controlled-pore glass in the presence of iron(III). Chromatographic determination of dinoseb in lemon juice.
abstract: The efficiency of an adsorbent consisting of quinolin-8-ol immobilized on controlled-pore glass which was packed in a minicolumn to preconcentrate nitrophenols in the presence of iron(III) has been established. Retention was carried out at acidic pH in the presence of 20 mM iron(III). Methanol-30 mM formic acid-sodium formate aqueous solution (pH 4.2) (65:35) was used in a one-step elution. Determinations were carried out by using liquid chromatography with detection at 350 nm. Determination of trace amounts of dinoseb in lemon juice was carried out with a minimum sample preparation. Recoveries were between 89 and 100% at 200-33 micrograms l-1. The maximum admissible concentration in fruit juice dictated by the Spanish and European Community legislation can be measured.
mesh_terms: D019297:2,4-Dinitrophenol / Q000031:analogs & derivatives* / Q000032:analysis; D000327:Adsorption; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002957:Citrus / Q000737:chemistry*; D005898:Glass; D006912:Hydroxyquinolines; D007501:Iron; D008832:Microchemistry; D010575:Pesticides / Q000032:analysis*; D011786:Quality Control; D012996:Solutions