TABLE 3

Stability of AQ and DAQ in spiked plasma samples (n = 3)

StabilityBias (%) by concn
Low (150 ng/ml)Medium (300 ng/ml)High (900 ng/ml)
Storage stability (−20°C)
    DAQ
        30 days2.83−4.126.95
        90 days3.40−8.146.51
    AQ
        30 days6.44−6.694.22
        90 days7.62−6.683.92
Freeze-thaw stability (−20°C and 25°C)
    DAQ0.85−4.327.95
    AQ9.17−5.974.10
Bench stability (25°C; 24 h)
    DAQ−7.81−7.768.29
    AQ8.51−6.303.99