COLIKAT RAPID is a fast test to simultaneously detect both total coliforms and Escherichia coli in water samples providing the test’s results within 18 hours. COLIKAT RAPID is suited for the entire water matrix.

The water samples to be tested are incubated overnight so that they are ready to read early the next day. Therefore COLIKAT RAPID delivers significant workflow benefits and speed in the event of a contamination issue. The test’s high sensitivity enables early coliform detection in water distribution systems, assisting to help to reduce biofilm buildup and sporadic downstream contamination events. As compared to the alternative conventional method using Chromogenic Coliform Agar (CCA; ISO 9308-1) for detection, COLIKAT RAPID significantly reduces false alarms created by inaccurate false positive results which give rise to uncertainty and unnecessary expense.

  • Simultaneous detection and quantification of Escherichia coli and total coliforms for the entire water matrix.
  • Sample evaluation after 18 hours.
  • Optimized workflow in your laboratory: The sample evaluation takes place after 18 hours before the reception of next days’ samples.
  • Enumeration of Escherichia coli and coliform bacteria in water samples acc. to EN ISO 9308-2.

Test Principle

COLIKAT RAPID uses certain specific characteristics of both Escherichia coli and coliform bacteria for identification of the species. The test contains MUG and ONPG, two common nutritional indicators. Coliform bacteria use their enzyme ?-Galactosidase to metabolize ONPG turning the sample yellow. Escherichia coli – other then most coliform bacteria – additionally has the enzyme ?-Glucuronidase that enables it to hydrolyze MUG so that the sample additionally shows fluorescence under UV-light.

Most of non-coliform bacteria possess neither the ?-Galactosidase nor the ?-Glucuronidase. Therefore, they cannot transform MUG and ONPG and the test will not detect them. Yet, some non-coliform bacteria contain the enzymes. COLIKAT RAPID therefore uses selective supplements that inhibit the growth of those bacteria. The combination of the test’s enzymes and selective supplements prevents some common problems of conventional culture methods such as Chromogen Coliform Agar CCA (EN ISO 9308-1):

  • False positive results are prevented (for example for Aeromonas spec.)
  • The growth of non-target organism is prohibited. This way non-target organisms cannot affect (or even inhibit) the growth of Escherichia coli and coliform bacteria

Presence/ Absence:

Presence/ Absence: Add COLIKAT RAPID to 100 ml of
water sample and incubate for 18 hours at 36°C ± 2°C.

For presence/absence testing incubate the sample for 18
hours and read-off the result: If the sample turned yellow,
coliforms are present. If it shows fluorescence unter UVlight Escherichia coli is present.


For quantitative testing add COLIKAT RAPID to 100 ml.

Pour the 100 ml sample into the COLIKAT Enumeration Tray.

Seal the COLIKAT Enumeration Tray with the
COLIKAT Seal applicator.

Incubate the sample for 18 hours at 36°C ± 2°C.

Count the yellow wells of the COLIKAT Enumeration Tray
(= coliforms). Count the yellow wells of the COLIKAT
Enumeration Tray that show fluorescence (= Escherichia

Transform the count results to the number of CFU in the sample by using the MPN table in the appendix to EN ISO 9308-2.

Colikat Rapid:

Product code Product Name Format Quantity/per pack Minimum order quantity
89-4000 COLIKAT RAPID kit 25 1
available Q1 2020 Enumeration Tray available Q1 2020 available Q1 2020 1
available Q1 2020 Seal Applicator available Q1 2020 available Q1 2020 1
available Q1 2020 Sample Vessels available Q1 2020 available Q1 2020 1
available Q1 2020 Compare Kit available Q1 2020 available Q1 2020 1
available Q1 2020 QC Strains available Q1 2020 available Q1 2020 1