Testing 2mL-100mL Aqueous Samples on R-Card® Using Membrane Filter
NO MORE PETRI DISHES to test water or food and beverage samples for E. coli, Enterococcus, or various other microbes with the R-CARD® from Roth Bioscience, LLC.
There are now 2 different size cards, the original which is 3.5" x 3" that takes 1mL inoculum and the second card 44.5" x 4" that is designed to take up to 3mL inoculum.
For samples that contain high bacterial levels, just add a 1-3 mL inoculum (undiluted or diluted) to the R-CARD® base, drop the top on it, allow to spread, and incubate. Results will be counted and are quantitative. (No reading MPN for an estimated range, and no presence/absence with no actual numbers.)
For samples that contain very low microbial counts, where a 1-3 mL inoculum is not sufficient to result in statistically reliable results, or a large sample is desired or required, the use of a 47 mm, 0.45 µm micropore filter may be used to filter the sample, and is easily adaptable for use with the 3.5" x 4" size card. Just filter the desired size sample, lift the top card film, and place the filter (right side up) containing the microbes on the R-CARD® bottom, add 1ml sterile water onto the filter and drop the top part onto it. Allow the water to spread over the filter, incubate appropriately and count the resulting CFUs.