Device to hold growth medium|by identifying associated gas or vapour and differentiating it from gas of vapour associated with other bacteria

Bacteria are detected by detecting gas or vapour associated with them, and also differentiating from gas or vapour associated with other bacteria.Detection appts. for carrying out the process is also claimed.Gas or vapour from an enclosed space above a Petri dish or other culture dish is diverted to flow over an array of sensors which have electrical properties varying according to exposure to gases or vapours. The response of the sensors is observed.The sensors pref. consist of semiconducting polymers whose resistance or impedance varies according to the exposure. The response of the sensors may be compared against a library of responses. Alternatively, the response may be input to a neural network trained against known bacteria.The array of sensors is pref. first purged with a purging gas.USE - The method may be used to identify bacteria, e.g. Staphylococcus aureus, Escherichia coli and Group A beta-haemolytic streptococci.The method may also be used for the detection of microfungi.ADVANTAGE - The method can differentiate between closely related bacteria or microfungi in a simple manner.