According to the American Animal Hospital Association, canines are 2-5 times more likely to develop lymphoma than humans; however, only 4% of canines are diagnosed during a routine appointment1,2. This work focused on modifying a novel fiber-based diagnostic to enhance heterogenous cell sample separation for rapid, routine lymphoma diagnosis. Through fiber size, configuration, biomaterial, and surface modifications, this work focused on optimizing the passive wicking properties of the fiber bundle. A dopamine-treated polylactide (PL) fiber bundle and twisted nylon fiber bundle had the most favorable wicking properties. This work also focused on identifying a biomaterial cap on the fiber bundle to promote cell wicking and capture. Alginate, three-dimensional printed PL and paper-based materials were tested. A freeze-dried sodium alginate hydrogel material was identified as the most promising biomaterial cap. Further fiber bundle and cap biomaterial optimization for increased cell recovery and cell visibility will lead to a clinically relevant prototype.