Hacettepe University, Chemical Engineering Department, Ankara, Turkey.
J Chromatogr A. 2012 Feb 10;1224:43-50. doi: 10.1016/j.chroma.2011.12.043. Epub 2011 Dec 19.
A new class of monodisperse macroporous beads in the hydrophilic form were synthesized by seeded microsuspension copolymerization of two acrylic crosslinking agents, glycerol dimethacrylate (GDMA) and glycerol-1,3-diglycerolate diacrylate (GDGDA). The monodisperse porous poly(glycerol dimethacrylate-co-glycerol-1,3-diglycerolate diacrylate), poly(GDMA-co-GDGDA) beads were highly hydrophilic in nature due to hydroxyl functionality resulting from both crosslinking agents. The beads with different particle sizes between 4.5 and 6.7 μm and with different porous properties were obtained by changing the seed latex to monomer ratio. The bead size decreased, the average pore size increased and the specific surface area decreased with increasing seed latex to monomer ratio. Poly(GDMA-co-GDGDA) beads were slurry packed in microbore and semimicro-HPLC columns and successfully used as a stationary phase in aqueous size exclusion chromatography (SEC) mode in a micro-liquid chromatography system. The aqueous SEC runs were performed by using dextran standards in the molecular weight range of 1000-670,000 Da. SEC calibration curves exhibiting linearity in a wider range of molecular weight were obtained with the semi-micro and micro-HPLC columns packed with the poly(GDMA-co-GDGDA) beads synthesized with the seed latex to monomer ratios of 0.038 and 0.058 g/mL. The dextran standards could be eluted in an analysis time shorter than 2 min using micro or semi-micro columns packed with poly(GDMA-co-GDGDA) beads as stationary medium. These packings are suitable for molecular weight determination between 5×10(3) and 5×10(5) Da in the aqueous medium by using mobile phase flow rates in the range of 25-250 μL/min. The average molecular weight determinations of different water soluble polymers, an ionic polymer, poly(2-dimethylaminoethyl methacrylate), a zwitterionic polymer, poly([2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide), and a non-ionic polymer, poly(vinyl alcohol) were performed on a semimicro-column packed with the poly(GDMA-co-GDGDA) beads. Satisfactory results were obtained in the molecular weight determination of hydrophilic polymers by aqueous SEC.
通过两种丙烯酸交联剂，甘油二甲醚（GDMA）和甘油-1,3-二甘油二丙烯酸酯（GDGDA）的种晶乳液共聚合成了一类新的亲水性单分散大孔珠。由于两种交联剂均具有羟基官能团，因此单分散多孔聚（甘油二甲醚-co-甘油-1,3-二甘油二丙烯酸酯）珠具有很高的亲水性。通过改变种子乳液与单体的比例，获得了粒径在 4.5 至 6.7 μm 之间且具有不同多孔特性的珠。随着种子乳液与单体的比例增加，珠的粒径减小，平均孔径增大，比表面积减小。将聚（GDMA-co-GDGDA）珠浆填充到微径和半微径 HPLC 柱中，并在微液相色谱系统中以水相排阻色谱（SEC）模式成功用作固定相。在 SEC 运行中，使用分子量范围为 1000-670,000 Da 的葡聚糖标准。通过使用具有 0.038 和 0.058 g/mL 种子乳液与单体比例的半微径和微径 HPLC 柱填充聚（GDMA-co-GDGDA）珠获得的 SEC 校准曲线，在更宽的分子量范围内显示出线性。使用微或半微径填充聚（GDMA-co-GDGDA）珠作为固定相的柱，可在少于 2 分钟的分析时间内洗脱葡聚糖标准。这些填料适用于在水性介质中通过流动相流速在 25-250 μL/min 范围内在 5×10（3）至 5×10（5）Da 之间的分子量测定。在半微径柱上对不同水溶性聚合物、离子聚合物聚（2-二甲氨基乙基甲基丙烯酸酯）、两性聚合物聚[2-（甲基丙烯酰氧基）乙基]二甲基-（3-磺丙基）铵氢氧化物和非离子聚合物聚（聚乙烯醇）进行了平均分子量测定。在水性 SEC 中对亲水性聚合物的分子量测定获得了令人满意的结果。
