A spike recovery test yields 130% recovery. What does this indicate?

A spike recovery test yields 130% recovery. What does this indicate?

• A. Acceptable performance.
• B. Perfect method performance.
• C. Matrix effects or interference outside 80-120% range.
• D. Insufficient sample.

Answer: (C)

Spike recovery checks how accurately a method measures an analyte in the sample’s matrix by adding a known amount and seeing how much is recovered. The acceptable range is typically 80–120% because it accounts for normal variation without matrix interference. If you get 130% recovery, the measured amount is higher than what you added, showing a positive bias. This points to matrix effects or interferences that are altering the signal and pushing the result above the true value. It’s not about having too little sample or flawless performance; rather, the sample matrix is influencing the measurement outside the acceptable range. To fix this, you’d look into mitigating matrix effects (for example, through matrix-matched calibration or using an internal standard) so recoveries fall back into the acceptable window.

Spike recovery checks how accurately a method measures an analyte in the sample’s matrix by adding a known amount and seeing how much is recovered. The acceptable range is typically 80–120% because it accounts for normal variation without matrix interference. If you get 130% recovery, the measured amount is higher than what you added, showing a positive bias. This points to matrix effects or interferences that are altering the signal and pushing the result above the true value. It’s not about having too little sample or flawless performance; rather, the sample matrix is influencing the measurement outside the acceptable range. To fix this, you’d look into mitigating matrix effects (for example, through matrix-matched calibration or using an internal standard) so recoveries fall back into the acceptable window.