Canadian Forest Service Publications
A comparison of UV and fluorescence detectors in the liquid chromatographic analysis of glyphosate deposits after post-column derivatization. 1997. Sundaram, K.M.S.; Curry, J. Journal of Liquid Chromatography and Related Technology. 20:511-524.
Year: 1997
Issued by: Great Lakes Forestry Centre
Catalog ID: 34057
Language: English
Availability: PDF (request by e-mail)
Abstract
A sensitive and rapid liquid chromatographic method for the analysis of glyphosate using either post-column ninhydrin derivatization and UV detection (UV-D) or post-column reaction, fluorogenic labelling with o-phthalaldehyde in the presence of 2-mercaptoethanol andfluorescence detection (FD) is described. The sensitivity of the UV-D and two fluorescent detectors (HP-FD and Kratos-FD) were compared and evaluated to analyze glyphosate residues from glass fibre filter (GFF) discs used as deposit collectors in aerial application. The herbicide was extracted from the GFF discs using 30.0 mL of phosphate buffer adjusted to pH2.1, derivatized and quantified. The method was tested initially, optimized andvalidated byusing glyphosate standards. Theaverage percent recoveries from fortified GFF samples were 93.7 (UV-D), 99.2 (HP-FD) and 94.9 (Kratos-FD). The corresponding standard deviation and coefficient ofvariation (percent) were 6.0 and 6.44; 1.6 and 1.67; and 4.4 and 4.59, respectively. The minimum quantifiable limits (ng/50 uL injection) for UV-D, HP-FD and Kratos-FD were 49,16 and 28, respectively. The study showed that HP-FD was very sensitive compared to the other two detectors. The simplicity of the method allows high sample throughput for the routine analysis of glyphosate deposits.