Easy DryTM are absorbent pads saturated with a sterile, dehydrated culture medium. Each pad is pre-plated in a Petri dish and is immediately ready to use after pouring sterile distilled or deionized water on it. Easy DryTM are optimal for the examination of large sample volumes by the membrane filter method.
Easy DryTM C-EC MF is a selective medium used to assess microbial water quality on the basis of enzymatic reactions of bacteria. Its formula containing chromogenic and fluoregenic substrates allows the detection and confirmation of E. coli in 18-24 hours.
PREPARATION
1.
Cut open a bag and remove the number of Easy Dry plates needed.
2.
Moisten the pad contained
in the Petri dish with 2.2 ml of sterile distilled or deionized water.
3.
Wait 5 minutes before
using.
TEST PROCEDURE
Filter the sample through a filter membrane (0.45 μm pore diameter). Transfer the membrane onto a plate containing a just rehydrated pad. Incubate aerobically for 18-24 hours. Incubation temperature may vary depending on the target of the analysis:
• 37 ± 1°C to maximize total coliforms detection;
• 44 ± 0.5°C if research is focused on fecal coliforms and E. coli.
INTERPRETING RESULTS
Examine the membrane for growth. Count all blu-green colonies as total coliforms. Report the count as CFU per ml of sample allowing for dilution factors. Escherichia coli will appear as fluorescent colonies under UV light (366 nm). To confirm presence of E. coli by indole reaction overlay the medium with Kovac’s reagent (ref.
87001). The layers turns red within 2 minutes in case of positive reaction.
APPEARANCE OF THE MEDIUM
Whitish pad. Yellowish once rehydrated.
STORAGE
Store at 10-25°C away from light. Do not
use the product beyond its expiry date on the label or if product shows any
evidence of contamination or any sign of deterioration.
SHELF LIFE
2 years.
