For the weekly quality control testing of the RAST method, place four sterile glass tubes on a tube stand. Dispense sterile saline into the tubes. Next, transfer the QC strain from the isolated colonies of an overnight culture into the first tube to create a 0.5 McFarland suspension.
With a sterile pipette and tip, transfer 10 microliters of the suspension from the first tube to the second tube. Once mixed, transfer 10 microliters of the suspension from the second to the third tube, and then to the last tube. Next, take one milliliter of the inoculum from the last tube with a sterile syringe.
Transfer the inoculum into an automated blood culture bottle after swabbing the septum with 70%isopropyl alcohol. Simultaneously with a separate sterile needle, add five milliliters of sterile sheep blood into the same blood culture bottle. Incubate it in a continuous blood culture monitoring system until it flags positive.
