Bladder Cancer Cell Capture: Elucidating the Effect of Sample Storage Conditions on Capturing Bladder Cancer Cells via Surface Immobilized EpCAM Antibody

The gold standard to detect bladder cancer, cystoscopy, is an invasive procedure requiring ambulant hospitalization, thus presenting an obstacle for routine diagnosis. We aim to develop a noninvasive detection method as an alternative that selectively captures shed cancer cells in the patient's urine via surface-immobilized anti-EpCAM antibody. However, the urine sample storage conditions prior to analysis affect the subsequent cancer cell capture rates by the device. In this study, we investigate the capture rates of HT1197 and HT1376 bladder cancer cells in different media (fresh and aged urine as well as PBS) and storage temperatures prior to analysis (37 and 4 °C) as well as in the presence of adjuvants in the medias (free antibodies and cell debris). Capture efficiencies decreased in as little as 1 h of the sample being incubated at 37 °C in all media studied here. Furthermore, cell debris played a strong part in reducing the capture efficiency. From the data, we conclude that storing the sample at 4 °C resulted in the best capture efficiency if storage of more than 1 h was required, which gave valuable insights for this sensor's translation from laboratory to real-world applications.