Abstract: An example of a flow cell includes a substrate having depressions separated by interstitial regions. First and second primers are immobilized within the depressions. First transposome complexes are immobilized within the depressions, and the first transposome complexes include a first amplification domain. Second transposome complexes are also immobilized within the depressions, and the second transposome complexes include a second amplification domain. Some of the first transposome complexes, or some of the second transposome complexes, or some of both of the first and second transposome complexes include a modification to reduce tagmentation efficiency.