Claudio Araneda, Paulina Villar, Carolina Cuadros, Mauricio del Valle, Pia Nunes and Margarita Santelices
Pharmacokinetics of Enrofloxacin (ENR) and Ciprofloxacin (CPX) in pig plasma was studied by HPLC-FL analysis using two injectable solutions, Enromic ® 20% (single dose of 7.5 mg ENR Kg -1 body weight) and Enromic ® 10% (multiple dose of 2.5 mg ENR Kg -1 body weight/day during 3 consecutive days). For the method validation, standard calibration curves were prepared between 0.025 and 0.5 μg mL -1 , with r 2 >0.9998 for both analytes. Quantification limits were 0.0282 and 0.0289 μg mL -1 for ENR y CPX, respectively; recovery percentages vary between 90.09% and 104.84% for ENR, and 63.01% and 89.01% for CPX, and precision obtained for measurements made on different days, expressed as %RSD, varied between 2.70% and 15.26% for ENR, and between 6.58% and 13.31% for CPX. Pharmacokinetic parameters gave values for Enromic ® 20% of 1.139 ± 0.320 μg mL -1 (C max ), 3.500 ± 1.581 h (T max ) and 17.821 ± 3.020 μg mL -1 h (AUC 0→∞ ) DU for ENR and 0.047 ± 0.010 μg mL -1 (C max ), 9.200 ± 1.932 h (T max ) and 1.027 ± 0.138 μg mL -1 h (AUC 0→∞ ) for CPX . For the product Enromic ® 10% (multiple doses), values were 0.428 ± 0.119 μg mL -1 (C max ), 5.000 ± 0 h (T max ) and 4.616 ± 1.138 μg mL -1 h (AUC 0→∞ ) for ENR and for CPX were 0.023 ± 0.006 μg mL -1 (C max ), 6.000 ± 2.108 h (T max ) and 0.424 ± 0.129 μg mL -1 h (AUC 0→∞ ) . We conclude that the most analyzed parameters are similar for both products, regardless of their different administration regime.