Method for quantification of biological material in a liquid sample

A method for quantification of a microorganism in a liquid sample, comprising the steps of:

• providing a bag having an upper surface sheet and a lower surface sheet enclosing a volume therebetween, said bag having an upper opening through which the liquid sample can be poured into said volume in said bag;
• wherein the bag is made of a material which can be caused to form discrete non-permeable compartments for holding the liquid sample and the bag is provided with a plurality of rows of partitions configured to separate said liquid sample into separate portions;
• adding a testing medium to the liquid sample to form a leading sample;
• placing the testing sample in said bag;
• distributing the testing sample within the bag;
• forming a plurality of discrete non-permeable wells within a plurality of compartments such that each compartment contains one well in the bag so that the testing sample is secured in a plurality of separate aliquots in said wells within the compartments;
• and
• detecting the presence or absence of said microorganism in each of said well.