జర్నల్ ఆఫ్ ఎనలిటికల్ & బయోఅనలిటికల్ టెక్నిక్స్

నైరూప్య

ViewLux? Microplate Imager for Metabolite Profiling: Validation and Applications in Drug Development

Julien Bourgailh, Maxime Garnier, Robert Nufer, Hans Pirard and Markus Walles

Generation of early information on metabolic pathways, metabolite structures and their systemic exposure is a highly time consuming activity during the drug development process. Since these data have become of higher interest for the health authorities, efforts have been made to provide results as early as possible. ViewLux UltraHTS Microplate Imager is an instrument originally designed for high throughput in biological assays requiring luminescence, absorbance or fluorescence detections. In this work, we evaluate the capability of the new generation of the instrument for both ¹⁴C and ³H detection. We discuss data processing of the Viewlux, especially the background subtraction in comparison to conventional TopCount^® instruments, as this has an impact on the limit of detection for samples containing low amounts of radioactivity like samples originating from ADME studies. We demonstrate that the limit of detection can be lowered by prolonging the exposure time for ³H labeled compounds up to 2 h. We validated the ViewLux for our metabolite profiling applications (in vitro and in vivo ADME samples) in early drug development using UPLC followed by fraction collection in 384 well plates and demonstrated for our applications that limits of detection of 2.2 and 24 dpm/well for ¹⁴C and ³H, respectively could be reached and that the throughput could be increased by at least two fold compared to conventional Topcount detection. We also demonstrate in this work how endogenous interferences resulting in false positive peaks in samples containing low amounts of radioactivity can be overcome by using a customized light filter.