Provided here are cell detection systems, fluidic devices, structures and techniques related to particle and cell sorting and detection in fluid, for example sorting specific subpopulations of cell types. A method for verification of sorting of particles includes receiving a first detection signal that is associated with optical characteristics of a particle in a first channel. A sorting channel of a plurality of second channels is determined based on the first detection signal, thereby determining the sorting of the particle into the sorting channel based on the optical characteristics of the particle. A sorting signal for sorting the particle from the first channel into the sorting channel is transmitted. A second detection signal is received that is associated with the presence of the particle in the sorting channel. The sorting of the particle from the first channel into the sorting channel is verified based on the second detection signal.