The U‑PLEX platform makes it easy to create multiplex immunoassays. Using two simple tools - U‑PLEX 384-well plates and unique Linkers - you can build multiplex panels for any combination of analytes. The analytes in the U‑PLEX menu are organized into U‑PLEX Groups. Assays within the same U‑PLEX Group have been tested for multiplex compatibility and can be combined in panels with confidence. The U‑PLEX Custom Biomarker Group 1 (mouse) products (Table 1) enable multiplex panels that combine U‑PLEX biomarker assays with other content. They are fulfilled with a U‑PLEX plate where some of the spots measure U‑PLEX analytes and some of the spots are left “open”. The “open” spots can be used for custom content such as MSD’s R-PLEX Antibody Sets or antibodies from other sources. Ordering a Custom U‑PLEX assay is simple and can be done online with our U‑PLEX Assay Designer.