Fig. 1.

Time course of 0.35 mM tetranitromethane (TNM) modification of 1 mg/ml h2E2 mAb (0.35 mM tyrosine residues) at 22°C in 50 mM Tris-Cl pH=8.0 buffer. The UV/Vis absorbance spectra were recorded 0–90 min after addition of TNM. The absorbance increase at 350 nm is due to nitroformate ion formation resulting from TNM reacting with mAb tyrosine residues. Inset - The increase in absorbance at 350 nm due to the nitroformate ion is plotted as a function of time after addition of TNM to the mAb.