Jet Flow Power Control for Object Sorting

A microfluidic actuator for selecting objects in a fluid stream comprising a plurality of objects, the actuator comprising:

• an object detection means adapted for, upon arrival of an object, identifying whether an object is an object of interest,
• a heater adapted for generating a jet flow for deflecting an object of interest from the fluid stream, and
• a controller configured for activating the heater as function of the detection of an object of interest using a nucleation signal;
• wherein the controller is configured for obtaining temperature information of the heater and for adjusting a nucleation signal for the heater taking into account the obtained temperature information, and wherein the controller is adapted for sending a probe pulse to the heater for measuring the temperature before a jet flow inducing nucleation pulse is fired for generating the jet flow, the probe pulse having an amplitude and duration low enough such that the temperature of the heater falls back to a baseline after the probe pulse is turned off and before the nucleation pulse is turned on.