Trialkylphosphines tris(2-carboxy-ethyl)-phosphine and tris(3-hydroxypropyl)-phosphine are popular reagents for the reduction of cysteine residues in bioconjugation reactions using maleimides. However, it has been demonstrated that these phosphines are reactive toward maleimide, necessitating their removal before the addition of the Michael acceptor. Here, a method using water-soluble PEG-azides is reported for the quenching of trialkylphosphines in situ, which is demonstrated to improve the level of maleimide conjugation to proteins.

中文翻译：

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使用水溶性 PEG-叠氮化物原位淬灭三烷基膦还原剂可改善马来酰亚胺与蛋白质的结合

三烷基膦三(2-羧基-乙基)-膦和三(3-羟丙基)-膦是使用马来酰亚胺在生物共轭反应中还原半胱氨酸残基的常用试剂​​。然而，已经证明这些膦对马来酰亚胺具有反应性，因此必须在添加迈克尔受体之前将其除去。在这里，报道了一种使用水溶性 PEG-叠氮化物原位淬灭三烷基膦的方法，该方法被证明可以提高马来酰亚胺与蛋白质的结合水平。