double-stranded dna from calf thymus was irradiated in the presence of bovine serum albumin ( bsa ) at a ratio of 1:10 by mass under air , n2 or n2o , with and without ethanol , tert-butanol or isopropanol in 10 ( -2 ) mol dm-3 sodium phosphate buffer , ph 7.0 .
C0001962
ethanol
C0022237
isopropanol