A gas chromatographic system with wide-bore capillary columns and synchronized accumulating radioisotope detector (SARD) was developed. A direct injection method and constant-flow regulation were applied. The performance of wide-bore capillary columns was good and the correspondence of the resolution obtained with SARD and that with mass detection was excellent. It was proved that the apparatus could detect of the order of 1 pg of 3H-labelled substances (3.7 TBq/mmol) and compete in terms of sensitivity with gas chromatography-mass spectrometry.