Figure 5From: Facile spectrophotometric assay of molar equivalents of N-hydroxysuccinimide esters of monomethoxyl poly-(ethylene glycol) derivatives Response of absorbance at 420 nm to ethanolamine quantities in reaction mixtures. A: Reactions continued for 15 min at 55°C followed by cooling with tap water. B: Reaction was allowed to continue for 90 min at 37°C.Back to article page