A method and system for recovering CO2 from gasification gas, prevents the recovered CO2 from being contaminated with COS, without repeating cooling and heating operations and without increasing the steam consumption. The apparatus may also contain the concomitant use of rectilinear reciprocation motion in addition to ultrasonic motion or energy along the shaft of the apparatus. Then the entire unit is shifted between its two terminal positions even prior to curing of the adhesive, the components then aligning themselves. The bearing bush has the actuating shaft mounted therein. Specifically, the invention relates to methods and systems for the detection of target entities using the signal observed in a noble element complexed to the biosensor.