Electrochemical detector systems

A method for detecting a micro-organism in a sample, comprising the steps of:

• i) passing said sample through the sample inlet of a filter device comprising a plurality of hollow fibre filter membranes and at least one detector system, said membranes having first and second ends, an outer surface and an inner surface defining a lumen, said first end of each of said membranes being open and communicating with said sample inlet and flow through said second end of each of said membranes being restricted such that said sample mixture is filtered through said membranes, leaving a filtrand in said lumen of said membranes, said at least one detector system comprising an electrode which runs through said lumen of said membranes;
• ii) optionally resuspending said filtrand from said lumen of said membranes;
• iii) detecting with said at least one detector system the presence of micro-organisms in said filtrand;
• and
• iv) correlating the results of detection step (iii) with the presence of said micro-organism in said sample.