In order to assure clear demonstration of weak D and partial D antigens, our Anti-D reagents have potentiators that may exhibit a false positive reaction if the reagents or relevant samples are tested at 18°C or below. These reactions are easy to identify, as they generally weaken at 37°C.
Our Anti-N and Anti-M reagents are very quick, requiring a short 5 minute incubation, at 20 – 25C. It is important that the reagents are at room temperature prior to testing. If these reagents are removed from the refrigerator and used immediately, it is likely that the incubation temperature will not be correct, and weak false positives may be seen.
The Anti-M reagent reacts optimally at pH 8.5 and is extremely sensitive to pH to allow for the testing to be completed with only 5 minutes of incubation. Buffered saline will affect pH levels, so be sure to utilize red cells suspended in unbuffered/ unstabilized normal saline.