The advantage of dual‐column approach and retention indices combined with refined reporting in gas chromatographic drug screening

Abstract

Abstract A dual‐column gas chromatographic retention index method was evaluated for the toxicological screening for basic drugs in autopsy blood samples. The dual‐column approach with DB‐5 and DB‐1701 capillary columns doubles the Identification Power of the corresponding single column methods. The long‐term intralaboratory variation of the dialkylfluoroaniline series based retention indices of drugs in blood ranged from 0.03% to 0.2% which was generally better than that obtained using the relative retention time. Novel software is described for the processing and reporting of the dual‐column chromatographic data in analytically useful form. Besides retention data, the response factors served as an additional identification factor.