Reaction products of NTPase/dATPase and phosphatase assays were analyzed by thin layer chromatography using polyethyleneimine-cellulose (PEI cellulose F) plates (purchased from Merck). For this, the chromatographic chamber was saturated with developing solution of formic acid (1 M), EDTA (1 mM) and LiCl 2 (0.5 M) for two hours. 0.5 ml reaction mixture was spotted on the PEI cellulose plate and the plate was kept in saturated chromatographic chamber for developing the chromatogram. The intensity of the spots was measured using a phosphor imager.