In AAV6 there were two unknown components in the empty capsids that were detected within the peaks containing the VP proteoforms (AAV6 Unknown Component 1 and AAV6 Unknown Component 2 in Table ), but not detected within the full capsids. Their absence in the full capsids suggests that they too were potential HCPs or some other cellular component. While not initially considered when undertaking this work, the ability of the ZipChip to rapidly visualize the presence of potential cellular components suggests that it might be able to be used as a rapid, orthogonal method to monitor the effectiveness of sample purification during downstream processing.