“…IS solutions of chloramphenicol were prepared in methanol to produce a final concentration of 100 ng/mL. QC samples were prepared at concentrations of 11.02, 275.50, and 551 ng/mL for 3,4-dihydroxybenzoic, 10.05, 502.50, and 1005 ng/mL for 5-CQA, 12.75, 1275, and 2550.00 ng/mL for 3-CQA, 28.2, 282, and 2820 ng/mL for CA, 15.50, 1550, and 2500 ng/mL for 4-CQA, 16.50.4, 825, and 1650 ng/mL for 1,3-diCQA, 10.13, 262.50, and 525 ng/mL for FA, 13.13, 262.50, and 525 ng/mL for 3,5-diCQA, 10.50, 210, and 420 ng/mL for 1,5-diCQA, 15.50, 310, and 620 ng/mL for 3,4-diCQA, 13.50, 675, and 1450 ng/mL for CAR, 15.25, 305, and 610 ng/mL for 4,5-diCQA, and 10.50, 1575, and 3150 ng/mL for ATR. All solutions were stored in the refrigerator at 4 • C until use.…”