TABLE 2

Validation data of the LC-MS/MS procedure for ZP in 1-mm hair segments

LOD (fg/1-mm hair)50
Recoverya (%; 20 pg/1-mm hair, n = 10)53
Linearityb (r2; 0.1-200 pg/1-mm hair)0.999
Intraday accuracy (%)
 5 pg/1-mm hair, n = 102.4
 50 pg/1-mm hair, n = 104.1
Precision RSD (%)
 5 pg/1-mm hair, n = 101.5
 50 pg/1-mm hair, n = 103.2
  • LOD, limit of detection; RSD, relative S.D.

  • a Recovery was calculated by comparing peak areas of ZP extracted from spiked samples with those spiked in hair extract.

  • b Linearity ranges were tested with seven different concentrations.