Hach Eclox, User Manual

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11.5 Reagent storage and preservation
The freeze-dried reagent can be kept at -18 °C until the expiration date shown on
the package.
Tubes that contain thawed but not reactivated freeze-dried luminescent bacteria
can be frozen again and kept on stock.
The reagent can be transported or shipped up to 7 days at no more than 25 °C.
11.6 Prepare the reagent
Prepare the Luminescent Bacteria Toxicity Test reagent not more than 4 hours
before testing according to ISO 11348 as done in this section.
The amount of light made by the luminescent bacteria is affected by the
temperature at which the reagent is reconstituted. The luminescent bacteria and
reconstitution solution must be mixed as cold as possible at refrigerator
temperatures (3 to 8 °C). If the temperature is higher, the amount of initial light
made by the bacteria will be lower.
11.6.1 Prepare the stock suspension using the LCK491
reagent
Prepare the stock suspension by adding the reconstitution solution to the
freeze-fried bacteria reagent. The reconstitution solution rehydrates the bacteria
reagent.
Reconstitution solution is specially made non-toxic ultra pure water. Do not make
reconstitution solution or use substitutes.
The stock suspension can be kept in a refrigerator (+8 °C) without being diluted
with Diluent as long as the validity criteria are met. Typically up to 4 hours. The
sensitivity spectrum of reactivated bacteria may shift as time elapses.
If the reagent is to be used 90 minutes or more after reconstitution, periodically
monitor the performance of the reagent with a suitable standard to show changes in
sensitivity.