Fig. 1From: GC-FID determination of nucleobases guanine, adenine, cytosine, and thymine from DNA by precolumn derivatization with isobutyl chloroformateChromatogram of separation of standards of nucleobases (1) A, (2) U, (3) T, (4) G, and (5) C as IBCF derivatives. GC conditions as in Fig. 2 Back to article page