Pharmacokinetic Study on Norfloxacin in Freshwater Shrimp

A 25 mg/kg dose of norfloxacin(NFLX)was given to freshwater shrimp by single muscular injection at 25-27 ℃ water temperature. A RP-HPLC method was developed to determine the norfloxacin concentration in hemolymph and muscle of freshwater shrimp(Penaeus orientalis). A two-compartment open pharmacokinetic model was used to describe the norfloxacin hemolymph and muscle concentration-time profile. The main parameters of hemolymph were as follows: t 1/2α 1.66 h, t1/2β 1.69 h, T(Peak) 1.82 h, C(max) 6.008 1 μg/mL, AUC 30.75 μg·mL-1·h-1, t1/2ka 0.96 h and the main parameters of muscle were as follows: t1/2α 0.08 h, t1/2β 4.42 h, T(Peak) 0.03 h, C(max) 16.72 μg/mL, AUC 12.34 μg·mL-1·h-1, t1/2ka 0.08 h. The results showed that NFLX would be absorbed by freshwater shrimp rapidly after single muscular injection and maintained at high concentration in tissues.