L-AA QC/STD expected concentration (µg/mL) Ret time (min) COV Measured concentration (µg/mL) COV REC4 (%)
             
Intermediate precision1 10 (L-AA STD) 3.038 ± 0.02 0.54 9.14 ± 2.46 2.46  
  50 (L-AA STD) 3.041 ± 0.01 0.30 48.61 ± 2.81 2.81  
  125 (L-AA STD) 3.042 ± 0.01 0.46 123.18 ± 1.96 1.96  
Intra-assay precision2 6.5 (QC) 3.023 ± 0.004 0.12 6.59 ± 1.644 0.38 101.41 ± 0.40
  55 (QC) 3.023 ± 0.003 0.11 56.76 ± 6.780 0.19 103.19 ± 0.19
  115 (QC) 3.022 ± 0.003 0.09 114.05 ± 8.568 0.12 99.18 ± 0.14
Injection precision3 55 (QC) 3.031 ± 0.02 0.52 54.11 ± 0.49 0.49  
1Intermediate precision values are means ± SD of three determinations (n=3) assayed over three separate days. 2Intra-assay precision values are means ± SD of three determinations (n=3) assayed on the same day. 3Injection precision values are means ± SD of six determinations (n=6). 4Spiked recovery method used for accuracy. Abbreviations: COV: Coefficient of Variation; L-AA STD, L-ascorbic acid Standard; QC: Quality Control; REC: Recovery
Table 2: Precision of the UV-HPLC method for the determination of L-ascorbic acid.