A system (1100, 1200), comprising: an input channel (1110, 1210) having a first end and a second end to receive particles through the first end; a sensor (1120, 1220) to categorize particles in the input channel (1110, 1210) into one of at least two categories; at least two output channels (1130a, 1130b, 1230a, 1230b), each output channel fluidically coupled to the second end of the input channel (1110, 1210) to receive particles from the input channel (1110, 1210), each output channel (1130a, 1130b, 1230a, 1230b) being associated with at least one category of the at least two categories, each output channel having a corresponding pump (1140a, 1140b, 1240a, 1240b) operable, based on the categorization of a detected particle in a category associated with a different output channel (1130a, 1130b, 1230a, 1230b), to selectively slow, stop, or reverse a flow of particles into the output channel (1130a, 1130b, 1230a, 1230b) from the input channel (1110, 1210), an output channel sensor (1150, 1250a, 1250b) provided in at least one of the at least two output channels (1130a, 1130b, 1230a, 1230b); and a controller coupled to the sensor (1120, 1220), to each pump (1140a, 1140b, 1240a, 1240b) and to the output channel sensor (1150, 1250a, 1250b), wherein the controller is configured to: receive a signal from the sensor indicative of categorization of a particle in a selected category of the at least two categories; and selectively actuate each pump corresponding to an output channel that is associated with a different category than the selected category, wherein the controller is configured to wait for a signal from the output channel sensor that the previous sorted particle has reached a predetermined point within the at least one output channel. an input channel (1110, 1210) having a first end and a second end to receive particles through the first end; a sensor (1120, 1220) to categorize particles in the input channel (1110, 1210) into one of at least two categories; at least two output channels (1130a, 1130b, 1230a, 1230b), each output channel fluidically coupled to the second end of the input channel (1110, 1210) to receive particles from the input channel (1110, 1210), each output channel (1130a, 1130b, 1230a, 1230b) being associated with at least one category of the at least two categories, each output channel having a corresponding pump (1140a, 1140b, 1240a, 1240b) operable, based on the categorization of a detected particle in a category associated with a different output channel (1130a, 1130b, 1230a, 1230b), to selectively slow, stop, or reverse a flow of particles into the output channel (1130a, 1130b, 1230a, 1230b) from the input channel (1110, 1210), an output channel sensor (1150, 1250a, 1250b) provided in at least one of the at least two output channels (1130a, 1130b, 1230a, 1230b); and a controller coupled to the sensor (1120, 1220), to each pump (1140a, 1140b, 1240a, 1240b) and to the output channel sensor (1150, 1250a, 1250b), wherein the controller is configured to: receive a signal from the sensor indicative of categorization of a particle in a selected category of the at least two categories; and selectively actuate each pump corresponding to an output channel that is associated with a different category than the selected category, wherein the controller is configured to wait for a signal from the output channel sensor that the previous sorted particle has reached a predetermined point within the at least one output channel. receive a signal from the sensor indicative of categorization of a particle in a selected category of the at least two categories; and selectively actuate each pump corresponding to an output channel that is associated with a different category than the selected category, wherein the controller is configured to wait for a signal from the output channel sensor that the previous sorted particle has reached a predetermined point within the at least one output channel.