My target is to conjugate about 150 kDa IgG Antibody to PEG micelles via the activation of PEG carboxylic acid with EDC and sulfo-NHS. Ab: DSPE-PEG(2000)Carboxylic ammonium (Avanti) (1:40, molar ratio) was adapted in my test. But I have no idea on the assay of the reaction products and am also wonder if 1) the ratio is in an appropriate range for effective conjugation, 2) I can add weighed EDC and sulfo-NHS powder directly to the DSPE-PEG2000 carboxylic ammonium in MES, pH 5. Can anybody give advice? Thanks a lot.