A method and device for testing sensors to be applied on a patient's skin for detection of liquid or moisture are described, in particular for monitoring vascular access in an extracorporeal blood treatment, in which a patient's blood is carried away from the patient via an arterial line and is fed to the patient via a venous line. A method for producing sensors to be applied on a patient's skin for detection of liquid or moisture is also described. The method and device according to the present invention are based on the testing of one or more moisture sensors which are taken from current production. The method includes providing a large number of twists of the moisture sensor applied onto a torsion body, the mechanical stresses thus recreating the stresses that can occur in practice when the moisture sensor is applied or stuck onto the patient's skin or forearm.

A method for detecting an analyte in a bodily fluid includes placing the detector in contact with at least one metabolite resulting from the metabolism or degradation of the analyte. The contact between the detector and the metabolite produces an optically detectable signal. The detection method includes the detection of the metabolite only in gas form, said metabolite in gas form coming from the evaporation of at least a part of said metabolite. The detection is also carried out without contact between the bodily fluid and the detector. A dressing for implementing the detection method is also described.

A wound dressing for wireless communication with a transceiver includes a radio-frequency antenna circuit disposed on a flexible substrate, and an electrochemical moisture sensor circuit disposed on a surface of the flexible substrate. An adhesive is provided to attach the wound dressing skin of a user. The electrochemical moisture sensor is arranged between the adhesive and the flexible substrate.