Abstract：
Glycosylation and phosphorylation rank as paramount post-translational modifications, and their analysis heavily relies on enrichment techniques. In this work, a facile approach was developed for the one-step simultaneous enrichment and stepwise elution of glycoproteins and phosphoproteins. The core of this approach was the application of the novel titanium (IV) ion immobilized poly(glycidyl methacrylate) microparticles functionalized with dendrimer polyethylenimine and phytic acid. The microparticles possessed dual enrichment capabilities due to their abundant titanium ions and hydroxyl groups on the surface. They demonstrate rapid adsorption equilibrium (within 30 min) and exceptional adsorption capacity for β-casein (1107.7 mg/g) and horseradish peroxidase (438.6 mg/g), surpassing that of bovine serum albumin (91.7 mg/g). Furthermore, sodium dodecyl sulfate-polyacrylamide gel electrophoresis was conducted to validate the enrichment capability. Experimental results across various biological samples, including standard protein mixtures, non-fat milk, and human serum, demonstrated the remarkable ability of these microparticles to enrich low-abundance glycoproteins and phosphoproteins from biological samples.
摘要：
糖基化和磷酸化是最重要的翻译后修饰，他们的分析在很大程度上依赖于富集技术。在这项工作中,开发了一种简便的方法，用于一步同时富集和逐步洗脱糖蛋白和磷蛋白。这种方法的核心是用树枝状聚合物聚乙烯亚胺和植酸官能化的新型钛（IV）离子固定的聚（甲基丙烯酸缩水甘油酯）微粒的应用。由于其表面上丰富的钛离子和羟基，微粒具有双重富集能力。它们表现出快速吸附平衡（在30分钟内）和对β-酪蛋白（1107.7mg/g）和辣根过氧化物酶（438.6mg/g）的特殊吸附能力，超过牛血清白蛋白（91.7mg/g）。此外，进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳以验证富集能力。各种生物样本的实验结果，包括标准的蛋白质混合物，脱脂牛奶,和人类血清，证明了这些微粒从生物样品中富集低丰度糖蛋白和磷蛋白的显着能力。
