nmol, of peptide) and 5.8 mg of avidin (Sigma, 40% protein by weight by amino acid analysis, 30 nmol) were dissolved in 0.4 mL of 0.1 M boric acid adjusted to pH 9 with NaOH. This mixture was photolyzed employing a Hanovia 450-W high-pressure mercury lamp (Ace Glass) within a Corning No. 3220 glass filter in a borosilicate immersion well15 for 1.5 h and then chromatographed on a 1.2 X 60 cm column of Sephadex G-50 (fine) in 1% NH4HC03 ...
