COMPARISON OF TLC-POSTLABELING AND HPLC-P-32-POSTLABELING ASSAY FOR CISPLATIN-DNA ADDUCTS

Calf thymus DNA, treated with the antitumour agent cis-diamminedichlor oplatinum(II) (cisplatin), was enzymatically digested with deoxyribonu clease I, snake venom phosphodiesterase and prostatic acid phosphatase , As a result the adducts were released with an unmodified nucleotide at their 5'-side, The adducts were postlabelled with [gamma-P-32]ATP a nd separated by thin-layer chromatography (TLC) and HPLC with on-line detection of P-32. One of the standards, platinated d(TGG), could be a nalysed with a recovery of 31% with both the TLC and the HPLC separati on systems, when the amount of adduct was between 0.5 and 100 fmol, In the case of platinated DNA the linear part of the concentration curve was from 100 fmol down to the lowest amount of adducts measured, 3.2 fmol, with the TLC system and between 8 and 40 fmol with the HPLC syst em. The recoveries of the adducts were 28% and 16% respectively.