A multiplexed bead-based flow cytofluorimetric assay for the screening of prohibited growth factors in doping control

Growth factors (GFs) are prohibited in sport doping and included in section S2 of the 2017 Prohibited List of banned substances released by the World AntiDoping Agency (WADA) [1]. In doping control, methods of detection of specific GFs, such as Growth Hormone (GH) and IGF-1, have already been developed and are currently part of the routine analytical procedures covered by ISO17025 accreditation at WADA laboratories [2-3]. For the analysis of several GFs, the utilization of single, different assays (one for each of the GF to be detected and quantified), can be very expensive and time consuming, expecially if single analytes assays are used for the initial testing screening procedures. Multiplexing flow cytofluorimetric arrays can simultaneously detect several analytes in just one assay [4]. This strategy significantly reduces sample pretreatment and time to get results in comparison with traditional ELISA and Western blot techniques and also represents a key strategy to get very high numbers of measurements rapidly . We have implemented a flow cytofluorimetric bead-based multiplex assay for the simultaneous screening of major isoforms of some banned growth factors.