Metabolite profiling from radiolabelled pre-clinical and Phase I ADME samples can be a time consuming process. The radiolabelled drug-related material in plasma and excreta from these studies is commonly quantified using high-performance liquid chromatography (HPLC) followed by radiochemical detection.
Microplate scintillation counting e.g. TopCount has allowed lower limits of detection, enabling more samples containing lower levels of radioactivity to be analysed. Samples are fraction-collected following HPLC separation into 96-well plates. However metabolite profiling using conventional HPLC can require long run times, which equates to fractionation into up to 6 plates. Using most commercially available fraction-collectors, samples have to be injected individually so that the scientist can change plates between each analysis. Only 18-20 plates (which equates to 3-10 samples depending on the HPLC method) can generally be run per day with no overnight or weekend runs possible.
By automating the Agilent 1100 HPLC instrument in the process, the samples can be processed overnight.