Figure 1From: Facile spectrophotometric assay of molar equivalents of N-hydroxysuccinimide esters of monomethoxyl poly-(ethylene glycol) derivatives Absorption spectra of conjugates of TNBS and some primary amines. Each tested primary amine in the borate buffer for reaction with TNBS was 100 μmol/L, unless otherwise stated. The reaction continued at room temperature for 120 min. 1: Ethanolamine, 2: Glycine, 3: n-butylamine, 4: Ethylenediamine, 5: 100 μmol/L TNBS + 300 μmol/L ethylenediamine, 6: TNBS alone.Back to article page