Siemens Healthcare Diagnostics, Advanced Technology and Pre-Development, 333 Coney Street, East Walpole, MA 02032, USA.
Org Biomol Chem. 2012 Mar 7;10(9):1883-95. doi: 10.1039/c2ob06807a. Epub 2012 Jan 25.
Improving reagent performance in immunoassays both to enhance assay sensitivity and to minimize interference are ongoing challenges in clinical diagnostics. We describe herein the syntheses of a new class of hydrophilic reagents containing sulfobetaine zwitterions and their applications. These zwitterionic reagents are potentially useful for improving the properties of immunoassay reagents. We demonstrate for the first time that zwitterion labeling is a general and viable strategy for reducing the non-specific binding of proteins to microparticles and, to improve the aqueous solubility of hydrophobic peptides. We also describe the synthesis of zwitterionic cross-linking reagents and demonstrate their utility for peptide conjugation. In automated, chemiluminescent immunoassays, improved assay performance was observed for a hydrophobic, small analyte (theophylline) using an acridinium ester conjugate with a zwitterionic sulfobetaine linker compared to a hexa(ethylene)glycol linker. Sandwich assay performance for a large analyte (thyroid stimulating hormone) was similar for the two acridinium ester labels. These results indicate that zwitterions are complementary to poly(ethylene)glycol in improving the aqueous solubility and reducing the non-specific binding of chemiluminescent acridinium ester conjugates.
提高免疫分析试剂的性能，以提高分析灵敏度并最小化干扰，这是临床诊断中持续面临的挑战。本文描述了一类新的含磺酸甜菜碱两性离子的亲水性试剂的合成及其应用。这些两性离子试剂在改善免疫分析试剂的性能方面具有潜在的用途。我们首次证明，两性离子标记是一种通用且可行的策略，可降低蛋白质与微球的非特异性结合，并提高疏水性肽的水溶性。我们还描述了两性离子交联试剂的合成，并证明了它们在肽偶联中的应用。在自动化化学发光免疫分析中，与使用具有六乙二醇接头的吖啶酯缀合物相比，使用带有磺酸甜菜碱接头的吖啶酯缀合物可以提高疏水性小分析物（茶碱）的分析性能。两种吖啶酯标记物的大分析物（促甲状腺激素）的夹心分析性能相似。这些结果表明，两性离子在提高亲水性和降低化学发光吖啶酯缀合物的非特异性结合方面与聚乙二醇互补。
