This PT sample is designed for the quantitative analysis of total and/or fecal coliform and E. coli.

The PT sample is provided in duplicate as a stable dehydrated Vitroid™ requiring hydration. The additional sample is provided for mishaps in the lab. NELAC prohibits the practice of multiple tests on a PT sample unless it is normal laboratory practice and multiple analysis is conducted on normal day to day samples.

A 100 mL of sterile hydration fluid is supplied with the PT sample. This is a phosphate buffer.

When prepared according to instructions, the concentration range of the sample will be between 20-2400 CFU/100mL as per NELAC Fields of Testing, January 4, 2010.

Store the PT sample at 4°C.

The dehydrated Vitroid™ sample is stable for a time exceeding the study schedule.

Due to the sensitivity of microorganisms and short holding times after hydration, please read entire instructions prior to preparation.

This sample is a single Vitroid™ and the possible concentration range is quite broad, it may be necessary to analyze the sample in a dilution series using general phosphate buffer solution.

This sample may be analyzed by any method appropriate for coliforms.

NOTE:  Analyte 6033 has been added for labs reporting to WA DOE only.  No other states need to report for this analyte at this time.

Allow the capped sample vial to equilibrate to room temperature.

While the sample is equilibrating to room temperature, warm the hydrating fluid in your incubator to 35-37°C. This will take about 60 minutes. This step is not necessary but will aide the dissolution of the Vitroid™. If you do not have the capability to warm the hydration fluid, all it to reach room temperature prior to starting the next step. The hydration fluid is sterile and may be stored at room temperature up to the expiration date listed on the bottom, refrigeration is not necessary for the hydration fluid.

Open the sample vial and aseptically transfer the Vitroid™ to the hydrating fluid. NOTE: The Vitroid™ is the colored disk on top of the cotton. The opaque beads below the cotton keep container dry and are not biologicals.

Allow the Vitroid™ to dissolve completely this may take up to 15 minutes. Mix by inverting gently several times, shaking may cause the cap to leak.

This represents the sample for analysis. Incubate at the temperature required by your method. Temperature requirements are rigorous, higher temperatures will kill the organisms and lower temperatures may suppress growth. Minimum incubation time is 24 hours. Further may be necessary depending on the method and media. Further dilutions are recommended to achieve a proper count, but base all counts on the whole volume sample. If you have questions don't hesitate to call RTC's Technical Support.  We will be more than happy to answer your questions: 1-800-576-5690 or 1-307-742-5452.