Abstract: There is provided a sample processing cartridge comprising a. a sample entry location; b. a closed sample processing chamber; c. a sample analysis location comprising a sample analysis well; d. a first channel fluidly connecting the sample entry location and the sample processing chamber; e. a second channel connecting the sample analysis location and the sample processing chamber, the second channel comprising a closed or closable second channel valve; wherein the sample processing chamber comprises a second channel port providing fluid connection between the second channel and the sample processing chamber, the second channel port being positioned in a sample accumulating region of the sample processing chamber. There is also provided a sample processing system comprising the cartridge, and methods of use of the cartridge and processing system in a sample processing assay.