Abstract: This disclosure concerns an exhaled breath collection device (1000) comprising a sensor unit (100) configured to measure a biomarker in exhaled breath, a cooling device configured to reduce a temperature of exhaled breath, a mouthpiece (300) configured to direct exhaled breath towards the cooling device, and a temperature control unit. In the exhaled breath collection device of the present disclosure, the temperature control unit is configured to control the cooling device to reach a target temperature which is set appropriately to correspond with the biomarker to be analysed.

Abstract: A fluid sampling element is adapted to receive a fluid sample, but also includes a pH sensor element adapted to measure pH of the fluid sample and a reference sensor element. The pH sensor element and the reference sensor element are adapted to generate a potential difference between each other based on the pH of the fluid sample. The pH of the fluid sample can be measured and the fluid sampling element can then be readily disposed of.

Abstract: A sub-millimetre hydrogen collector generator ring disc electrode is disclosed which may be used in a collector generator system, for example for measurement of mass transport rates using hydrogen as a tracer. A calibrator and calibration method as well as a method of assaying tissue perfusion is also disclosed.