| 
   
  |  | Amount taken (µg mL-1)
 | Amount added (µg mL-1)
 | Total amount found  (µg mL-1) (Mean ± SD)
 | Recovery (%) | RSD (%) |  
  | SAX | 25.00 | 25.00 | 50.75 ± 0.19 | 101.84 | 0.62 |  
  | 50.00 | 75.56 ± 1.41 | 99.85 | 2.03 |  
  | 75.00 | 99.56 ± 0.94 | 100.11 | 1.17 |  
  | MET | 0.00 | 12.50 | 12.75 ± 0.89 | 101.02 | 2.51 |  
  | 25.00 | 24.56 ± 0.70 | 99.27 | 1.55 |  
  | 37.50 | 37.06 ± 0.94 | 99.56 | 1.54 |  |