Question

To ensure proper and complete mixing, controls should be shaken vigorously for how long until all of the packed cells have been mixed from the bottom and side of the vial

a) 5 seconds
b) 10 seconds
c) 15 seconds
d) 30 seconds

Answer 1

Proper laboratory mixing of solutions with packed cells should continue until no cells remain on the sides or bottom of the vial, typically requiring 5 to 10 seconds of vigorous shaking. The exact duration may vary based on specific protocols or manufacturer guidelines.

Step-by-step explanation:

The question pertains to proper laboratory techniques for mixing solutions with packed cells, such as blood controls or cell suspensions. Specific protocols can vary, but generally, a vigorous agitation of the control vial is essential to ensure proper and complete mixing of the packed cells. A duration of 5 to 10 seconds is typical for small volume control vials, but the key is that the mixing should be done until there are no cells remaining unmixed at the bottom or sides of the vial. Furthermore, consistent and thorough mixing is crucial in laboratory practices to achieve accurate results, as seen in examples like sperm washing, making dilutions for counting cell concentrations, and preparing centrifuge tubes. However, without precise instructions from the material's specific protocol or manufacturer, the provided answer would be an educated suggestion based on common laboratory standards.