|Molecular Weight||169.073 g/mol|
Primesep 100 separates a mixture of glyphosate and isopropylamine by HPLC using cation exchange as a retention mechanism. The peak order of this mixture is reversed on a Primesep B column which uses anion exchange. This combination offers an alternative to ion chromatography for the simultaneous analysis of complex herbicide mixtures. Glyphosate, other phosphonomethyl herbicides, and their amine salts can be analyzed with a mobile phase mixture of water, acetonitrile (MeCN, ACN) and trifluoroacetic acid (TFA) and evaporative light scattering detection (ELSD).
Glyphosate is a broad spectrum herbicide used to kill weeds. It is the most used herbicide. Glyphosate is an aminophosphonic analogue of the natural amino acid glycine. Glyphosate and its intermediates are very polar ionic compounds derived from glycine. Neither of intermediates can be retained on traditional reversed-phase columns. Two methods for glyphosate intermediates were developed on Primesep B, Primesep B2 and Primesep 100 columns.
Glyphosate and intermediates/impurities of production are separated on an Obelisc N HILIC/ion-exchange column by a combination of HILIC and ion-exchange mechanism. Method can be used in analysis of glyphosate, iminodiacetic acid, (N-phosphonomethyl)-imminodiacetic acid, diethanolamine and related impurities in reaction mixtures, waste and ground waters. Detection techniques are LC/MS, ELSD, CAD and UV.
Glyphosate is broad spectrum herbicide to kill weeds. Presence of glyphosate in water, fruits and veggies is regulated. Alkylphosphonic acids are decomposition byproducts of chemical warfare agents. Analysis of phosphonic acid in water is regulated by Environmental Protection Agency (EPA). All phosphonic acids are polar acidic compounds. Method was developed for glyphosate and ethylphosphonic acid. Both compounds are retained by ion-exchange mechanism. Method is compatible with LC/MS and can be used for analysis of glyphosate and alkylphosphonic acids in various matrices.
Paraquat, diquat and glyphosate are three of most widely used herbicides in the world. Paraquat and diquat are very polar and very basic quaternary amines. Glyphosate is an aminophosphonic analog of glycine. It is very polar and acidic at most of the pH of the mobile phase. Since glyphosate and the quats have opposite charges no ion-pairing method can be developed for the mixture of basic and acidic herbicides. All three herbicides were separated on the Obelisc R tri-modal column. Paraquat and diquat are retained by a cation-exchange mechanism, and glyphosate is retained by weak reversed-phase and strong anion-exchange mechanisms. This method can be used for analysis of common herbicides in fruits, vegetables, ground water, drinking water and other matrices. Method is LC/MS compatible and can be used to determine trace levels of herbicides.
Glyphosate is a broad-spectrum herbicide which is used to kill weeds. Presence of glyphosate is strongly regulated by various governing agencies in the US, Europe, and Asia. Method for analysis of glyphosate in fruit juices and teas was developed using the Obelisc N HILIC/ion-exchange column. Glyphosate is retained by an ion-exchange mechanism. Since the method uses a highly aqueous mobile phase, which is not usual, for HILIC columns, none of the sugars, vitamins and other components of juices interfere with the analysis of glyphosate. Samples of juices were spiked with glyphosate. This method can be used in combination with LC/MS for determination of very low concentrations of glyphosate in various fruits and vegetables as well as ground and drinking water.
There is a need to separate different herbicides and pesticides in one run with LC/MS compatible conditions. Paraquat, diquat and glyphosate were separated on reversed-phase tri-modal cation- and anion-exchange column (Obelisc R) and on HILIC/ion-exchange columns (Obelisc N). Method explores unique properties of mixed-mode stationary phase which retains and separates cations like paraquat and diquat and anions/zwitter-ions like glyphosate in one run. Since columns are compatible with 100% organic and 100% water, a wide range of gradients can be used for analysis as well as isocratic conditions where it is desired. Method can be used for quantitation of these compounds in various matrices (soil, ground water, crops, food, etc.)