This paper reports the first mass measurement of specific microparticles and unicellular organisms on slides or dishes by using micropipette resonators with an open end. Micropipette resonators are fabricated by a customized pipette puller with a galvano mirror that widens the effective heating region thus makes pulled pipettes with a relatively long uniform cross-section. Pulled pipettes cut at a desired position to have an open end are then integrated with a piezo actuator and an optical pickup unit (OPU), originally used in optical data storage drives, for real-time frequency readout. The open-end micropipette resonators are thoroughly characterized with various liquids and particles. Silica microparticles and unicellular organisms, Paramecium Aurelia, sitting on a slide glass are successfully measured. This is the first demonstration of measurement-on-demand with fluidic channel integrated resonators.