At what speed and duration does the RPR test need to be rotated?

The RPR (Rapid Plasma Reagin) test is a crucial serological test used to screen for syphilis. The rotation speed and duration are vital for the test's accuracy and reliability. In the context of the RPR test, the recommended rotation speed of 100 RPM for 8 minutes is optimal to ensure adequate mixing of the reagents and plasma while allowing the formation of visible agglutination if reagin antibodies are present.

This specific combination of speed and time helps maintain the integrity of the reaction, permitting the appropriate formation of charcoal particles that are indicative of a positive result. Using a rotation speed that is too high or too low, or a duration that is not aligned with recommended practices, could potentially lead to inconclusive or inaccurate test outcomes, as the agglutination process may be compromised.

While other options suggest different speeds and durations, they do not align with the established guidelines for the RPR test, which prioritize both the efficiency of the test and the clarity of the results. Thus, 100 RPM for 8 minutes remains the most effective parameter for conducting the RPR test accurately.