Nominal concentration (ng/mL) Observed concentration a
(ng/mL, mean ± S.D.)
Precision b
(%)
Accuracy c
(%)
10 10.43 ±  0.76 7.28 104.26
40 40.43 ±  3.14 7.76 101.08
800 751.39 ±  33.04 4.40 93.92
1600 1591.11 ±  65.97 4.15 99.44

a n = 3 days with six replicates per day.
b Expressed as % R.S.D. (S.D./mean) × 100.
c Calculated as (mean determined concentration/nominal concentration) × 100.

Table 3: Inter-day assay precision and accuracy for curcumin in rat plasma.