Provided are methods of reducing and/or preventing interference by a drug comprising (i) an antibody Fc region and (ii) a moiety that binds to human CD47 in serological assays.

The present invention relates generally to a novel method using HPLC and fluorescence detection of free PEG-mal in PEGylated proteins and PEG-mal raw materials by adding a fluorescent label to the free PEG-mal.

Provided is an anti-PEG-antibody-binding material capable of detecting a methoxy-terminated-PEG-selective anti-PEG antibody. The anti-PEG-antibody-binding material according to an embodiment contains a cellulose oligomer represented by formula (1) and is bindable to a methoxy-terminated-PEG-selective anti-PEG antibody:

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wherein n represents an average degree of polymerization, which is a number of 6 to 16, and m represents an integer of 1 to 16.

The present invention relates to an improved method for separating and detecting of free or residual polyethylene glycol (PEG) in pegylated protein mixture. In particular, the method improves sensitivity, effective separation, and robustness of the quantification of free or residual PEG and related substance present in pegylated protein mixture which obtained as drug substance or drug product.