Preparation of poly(glycidylmethacrylate‐divinylbenzene) weak acid cation exchange stationary phases with succinic anhydride, phthalic anhydride, and maleic anhydride for ion chromatography

Abstract

In this work, poly(glycidylmethacrylate-divinylbenzene) microspheres were prepared and applied for the preparation of weak acid cation exchange stationary phases. Succinic anhydride, phthalic anhydride, and maleic anhydride were selected as carboxylation reagents to prepare three weak acid cation exchangers by direct chemical derivatization reaction without solvent or catalyst. The diameters and dispersity of the microspheres were characterized by scanning electron microscopy; the amount of accessible epoxy groups and mechanical stability were also measured. The weak acid cation exchangers were characterized by Fourier transform infrared spectroscopy; the content of carboxyl groups was measured by traditional acid base titration method. The chromatographic properties were characterized and compared by separating alkali, alkaline earth metal ions and ammonium and polar amines. The separation properties enhanced in the order of succinic anhydride, phthalic anhydride, and maleic anhydride modified poly(glycidylmethacrylate-divinylbenzene) cation exchangers.

Determination of betaine, l‐carnitine, and choline in human urine using a self‐packed column and column‐switching ion chromatography with nonsuppressed conductivity detection

“…A simple method previously reported by our laboratory was followed for producing the poly(GMA‐DVB) microspheres . Briefly, add a 0.3 g polyvinylpyrrolidone and 100 mL mixture of ethanol and water (95:5, v/v) into the flask, then a blend of 0.7 g azobisisobutyronitrile and 20 mL styrene within 30 min under the protection of dry nitrogen.…”

“…The poly(GMA‐DVB) microspheres with mass ratio of 1:1 (GMA to DVB) were prepared by two‐staged swelling and polymerization method. The MA modified poly(GMA‐DVB) microsphere has made a little modification from previous report . Preparation was as follow: a 2.0 g poly(GMA‐DVB) microsphere with mass ratio of 1:1 (GMA to DVB) was hydrolyzed in 0.05 mol /L sulfuric acid solution (H 2 SO 4 ) at 60°C for 10 h. Then, 10.0 g MA and 1.8 g dry hydrolyzed poly(GMA‐DVB) microspheres were added to a 25 mL round‐bottomed flask and stirred at 160°C for 4 h. Finally the microspheres were washed with water sufficiently.…”

“…Subsequently the pretreatment column (50 mm × 4.6 mm, id) was packed with the poly(GMA‐DVB) microspheres and the analytical column (150 mm × 4.6 mm, id) was obtained by modifying the poly(GMA‐DVB) microspheres with mass ratio of 1:1 (GMA to DVB) with MA. The columns were packed by a slurry method to ensure their efficiency and reproducibility . The self‐packed columns packing procedure in detail is described as follows: 1.8 g packing material was placed in 50 mL water and stirred for 10 min.…”

Simple determination of betaine, l‐carnitine and choline in human urine using self‐packed column and column‐switching ion chromatography with nonsuppressed conductivity detection

“…The poly(GMA‐DVB) microspheres were prepared according to our laboratory's recent report (Liu, Wang, Wu, Zhang, & Zhu, ). The SA modified poly(GMA‐DVB) microsphere was slightly modified from the previous report (Liu, Wang et al, ). Preparation was as follows: 2.0 g of poly(GMA‐DVB) microspheres with mass ratio of 1:1 (GMA to DVB) was hydrolyzed in 0.05 mol/L H 2 SO 4 solution at 60°C for 10 h. Then the microspheres were washed sufficiently with water.…”

“…was obtained by modifying the poly(GMA‐DVB) microspheres with mass ratio of 1:1 (GMA to DVB) with SA. The columns were packed using a slurry method to ensure their efficiency and reproducibility (Liu, Wang et al, ).…”