Method LMT taken,
µg mL-1
Intra-day accuracy and precision (n=7) Inter-day accuracy and precision  (n=5)
LMT found ± CL, 
µg mL-1
%RE %RSD LMT found ± CL, 
µg mL-1
%RE %RSD
A 1.0
3.0
5.0
0.99 ± 0.04
3.05 ± 0.12
4.98 ± 0.11
1.0
1.67
0.4
1.52
1.65
0.89
1.01 ± 0.03
3.03 ± 0.07
4.96 ± 0.14
1.0
1.0
0.8
0.98
0.86
1.02
B 4.0
8.0
12.0
4.05 ± 0.19
8.12 ± 0.24
12.02 ± 0.46
1.25
1.5
0.12
1.96
1.23
1.56
4.03 ± 0.17
7.98 ± 0.32
11.86 ± 0.65
0.75
0.25
1.17
1.55
1.46
1.99
%RE. Percent relative error, %RSD. relative standard deviation and CL. Confidence limits were calculated from: CL= ± tS/√n. (The tabulated value of t is 2.45 and 2.77 for six and four degrees of freedom respectively, at the 95% confidence level; S=standard deviation and n=number of measurements).
Table 2: Evaluation of intra-day and inter-day accuracy and precision.