Immobilization of polypeptides on a polyvinylidene difluoride membrane containing ENOL ester and sulfonate groups

摘要

A solid support having surface-attached carboxylic acid groups is reacted with an isoxazolium salt to form an activated support having enol ester and sulfonate groups. After washing to remove residual isoxazolium salt and base, the activated support is dried. A polypeptide is covalently or non-covalently bound to the support. The resultant immobilized polypeptide can be conveniently sequenced by N- and C-terminal sequencing methods. The support can be a polyvinylidene difluoride membrane or a glass fiber membrane having surface attached carboxylic acid groups, and the enol and sulfonate groups are provided by reacting the support with 2-ethyl-5'-phenylisoxazolium sulfonate. The dry support can be stored for at least about 3 months to achieve a peptide immobilization yield that is substantially the same as the yield obtained in the absence of drying.