College of Chemistry and Chemical Engineering, and Henan Key Laboratory of Fuction-Oriented Porous Materials, Luoyang Normal University, Luoyang 471934, PR China.
The Key Laboratory of Rare Earth Functional Materials and Applications, Zhoukou Normal University, Zhoukou 466001, Henan, PR China; International Joint Research Laboratory for Biomedical Nanomaterials of Henan, Zhoukou Normal University, Zhoukou 466001, PR China.
Talanta. 2018 Jul 1;184:235-243. doi: 10.1016/j.talanta.2018.02.021. Epub 2018 Feb 9.
Boronate affinity materials have attracted more and more attention in extraction, separation and enrichment of glycoproteins due to the important roles that glycoproteins take on in recent years. However, conventional boronate affinity materials suffer from low binding affinity mainly because of the use of single boronic acids. This makes the extraction of glycoproteins of trace concentration become rather difficult or impossible. Here we present a novel boronate avidity material, polyethyleneimine (PEI)-assisted boronic acid-functionalized silica nanoparticles (SNPs). Branched PEI was applied as a scaffold to amplify the number of boronic acid moieties. While 3-carboxybenzoboroxole, exhibiting high affinity and excellent water solubility toward glycoproteins, was used as an affinity ligand. Due to the PEI-assisted synergistic multivalent binding, the boronate avidity SNPs exhibited strong binding strength toward glycoproteins with dissociation constants of 10 M, which was the highest among reported boronic acid-functionalized materials that can be applied for glycoproteomic analysis. Such a high avidity enabled the selective extraction of trace glycoproteins as low as 0.4 pg/mL. This feature greatly favored the selective enrichment of trace glycoproteins from real samples. Meanwhile, the boronate avidity SNPs was tolerant of the interference of abundant sugars. In addition, the PEI-assisted boronate avidity SNPs exhibited high binding capacity and low binding pH. The feasibility for practical applications was demonstrated with the selective enrichment of trace glycoproteins in human saliva.
硼酸亲和材料由于在近年来在糖蛋白的提取、分离和富集方面发挥了重要作用，因此越来越受到关注。然而，由于传统的硼酸亲和材料仅使用单一硼酸，导致其结合亲和力较低，这使得痕量浓度的糖蛋白的提取变得相当困难或不可能。在这里，我们提出了一种新型的硼酸亲合力材料，即聚乙烯亚胺（PEI）辅助硼酸功能化的硅纳米颗粒（SNP）。支化的 PEI 被用作支架来扩增硼酸部分的数量。而 3-羧基苯并硼酸，对糖蛋白具有高亲和力和出色的水溶性，被用作亲和配体。由于 PEI 辅助的协同多价结合，硼酸亲合力 SNP 对糖蛋白表现出很强的结合强度，解离常数为 10M，这是可用于糖蛋白质组学分析的报道的硼酸功能化材料中最高的。这种高亲合力使得痕量糖蛋白（低至 0.4pg/mL）的选择性提取成为可能。这一特性极大地有利于从实际样品中选择性富集痕量糖蛋白。同时，硼酸亲合力 SNP 对丰富的糖的干扰具有耐受性。此外，PEI 辅助的硼酸亲合力 SNP 具有高结合容量和低结合 pH 值。通过选择性富集人唾液中的痕量糖蛋白，验证了其实际应用的可行性。
