Method for controlling the state of a pipette, pipetting procedure, pipetting device and suction tube for pipetting device

摘要

Method for controlling the state of a pipette (10) including a tube (12) of suction and a tip (14) of pipette in which - ultrasound is applied to the tube wall (12) suction generating the ultrasound a piezo actuator (18) and piezoelectric actuator attached to the tube wall (12) of suction and an additional weight (19) being fixed on the side opposite the tube (12) suction piezo actuator (18) to increase while the sensitivity, - the attenuation of the ultrasonic signal is measured as a function of frequency in a frequency range, - determining whether the pipette (14) contains or contacts the fluid by comparing the measured attenuation and frequency dependent in the frequency range with at least one reference measurement frequency dependent attenuation or a calibration curve based on reference measurements.