Advantages of the nutrient pads using the filter method


Tests for coliform bacteria and Escherichia Coli (E.Coli) by the membrane filter technique (see ISO 9308-1) are the most important routine microbiological examinations carried out on drinking water. These tests are based on membrane filtration by vacuum, subsequent culturing on a differential agar medium and calculation of the number of target organisms in the sample.


Picture shows Coliform Agar**

Mixed  culture  with Escherichia  coli (blue  colonies), Enterobacter aerogenes (purple colonies)and Pseudomonas  aeruginosa (beige colonies) after 20 hours at 37°



  • Nutrient pads are sterile, dehydrated culture media. Once they are moistened with sterile and demineralized (or distilled) water, they are ready to use immediately
  • Eliminates handling errors in the preparation of culture media
  • Dehydrated nutrient pads eliminates time-consuming and laborintensive preparation of culture media
  • Conforms to ISO 9303-1, ISO 7899, ISO 6222 and others
  • The visible colonies can be related directly to the sample volume. They give quantitative results. Compared with the direct method, considerably larger sample volumes can be tested. This concentration effect increases the accuracy of microbiological detection
  • Adequate for the determination of E. coli and coliforms, Enterobacteria, Salmonellae, wild yeasts, yeast and mold, etc. utilizing the different nutrient pad types
  • Typical application examples are not only the detection of microorganisms in the water, but also in beer, foods, milk, pharmaceuticals, soft drinks and wine
  • The incubated membrane filters are easy to file as a permanent record for convenient traceability
  • Our Membrane Filters are manufactured under GMP conditions ensuring consistent quality and high reproducibility from batch to batch and within each batch.
  • ** Chromogenic Coliform Agar (CCA), as per recommendation of the EUROPEAN UNION DRINKING WATER DIRECTIVE 98-83 EC and EN ISO 9308-1:2014

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