title: Solid-phase extraction and residue determination of glyphosate in apple by ion-pairing reverse-phase liquid chromatography with pre-column derivatization.
abstract: A new method for glyphosate residue determination in apple has been developed. A SPE cartridge was used to clean up the samples before derivatization. Glyphosate was derivatized with 4-chloro-3,5-dinitrobenzotrifluoride (CNBF) and quantified by reverse ion-pair liquid chromatography using cetyltrimethylammonium bromide (CTAB) as ion-pair reagent. In pH 9.5 H(3)BO(3)-Na(2)B(4)O(7) medium, the reaction of glyphosate with CNBF was complete after 30 min at 60 degrees C. The stability of the derivative on exposure to light at room temperature in methanol-water was demonstrated. The labeled glyphosate was separated on a Kromasil C(18) column (250 x 4.6 mm, 5 microm) at room temperature and UV detection was applied at 360 nm. Separation was achieved within 15 min in gradient elution mode. The correlation coefficient for the method was 0.9998 at concentrations ranging from 0.1 to 50 microg/g. The calculated recoveries for glyphosate in apple were from 86.00 to 99.55%, and the relative standard deviations (n = 6) were from 1.43 to 6.32. The limit of detection was 0.01 microg/g for glyphosate in apple.
authors: College of Agriculture and Biotechnology, China Agricultural University, Beijing, China.
authors: Kun
authors: K
authors: Qian
authors: Tao
authors: T
authors: Tang
authors: Tianyu
authors: T
authors: Shi
authors: Pingliang
authors: P
authors: Li
authors: Jianqiang
authors: J
authors: Li
authors: Yongsong
authors: Y
authors: Cao
mesh_terms: D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D005464:Fluorobenzenes / Q000737:chemistry; D005998:Glycine / Q000031:analogs & derivatives* / Q000032:analysis; D027845:Malus / Q000737:chemistry*; D009574:Nitro Compounds / Q000737:chemistry; D052616:Solid Phase Extraction; D013997:Time Factors; D000097797:Glyphosate
chemical_list: D000077286:Cetrimonium; D002593:Cetrimonium Compounds; D005464:Fluorobenzenes; D005998:Glycine; D009574:Nitro Compounds; D000097797:Glyphosate; C539305:4-chloro-3,5-dinitrobenzotrifluoride