A RP-HPLC method was used for the determination of eprinomectin concentration in sheep plasma following i.v. and s.c. administration at a single dose of 0.2 mg kg 1. Eprinomectin in plasma within 2.5200 ng ml 1 rang...A RP-HPLC method was used for the determination of eprinomectin concentration in sheep plasma following i.v. and s.c. administration at a single dose of 0.2 mg kg 1. Eprinomectin in plasma within 2.5200 ng ml 1 ranges had a good linear relationship(R=0.9968).The average recovery of the method was 99.65±3.84%.The RSD% of within-day and between-day assays were less than 10 and 12%, respectively. The extract of plasma samples were loaded onto a C 18 catridge. After solvent exchange, the methanol eluate was derivatized via the addition of 1-methylimidazole and trifluoroacetic anhydride in acetonitrile. The fluorescent derivative was analyzed.The main pharmacokinetic parameters were as follows, for i.v. administration: T 1/2β=12.66±2.05 h, AUC 0t= 1.02 ± 0.3 mg h L 1, f c=0.13±0.05; for s.c. administration: T 1/2Ka= 4.42 ±1.04 h, C max=0.02±0.01 μg ml 1, T max= 15.36 ± 2.91 h, t 1/2K=26.22±9.04 h, AUC 0t= 1.19±0.37 mg h L 1. The results showed that eprinomectin was distributed widely and taken long time to eliminate in sheep after i.v. adminstration. When given subcutaneously, eprinomectin had better absorption and longer residue time in sheep.Eprinomectin was eliminated much slowly after s.c. adminstration compared with i.v. administration.展开更多
文摘A RP-HPLC method was used for the determination of eprinomectin concentration in sheep plasma following i.v. and s.c. administration at a single dose of 0.2 mg kg 1. Eprinomectin in plasma within 2.5200 ng ml 1 ranges had a good linear relationship(R=0.9968).The average recovery of the method was 99.65±3.84%.The RSD% of within-day and between-day assays were less than 10 and 12%, respectively. The extract of plasma samples were loaded onto a C 18 catridge. After solvent exchange, the methanol eluate was derivatized via the addition of 1-methylimidazole and trifluoroacetic anhydride in acetonitrile. The fluorescent derivative was analyzed.The main pharmacokinetic parameters were as follows, for i.v. administration: T 1/2β=12.66±2.05 h, AUC 0t= 1.02 ± 0.3 mg h L 1, f c=0.13±0.05; for s.c. administration: T 1/2Ka= 4.42 ±1.04 h, C max=0.02±0.01 μg ml 1, T max= 15.36 ± 2.91 h, t 1/2K=26.22±9.04 h, AUC 0t= 1.19±0.37 mg h L 1. The results showed that eprinomectin was distributed widely and taken long time to eliminate in sheep after i.v. adminstration. When given subcutaneously, eprinomectin had better absorption and longer residue time in sheep.Eprinomectin was eliminated much slowly after s.c. adminstration compared with i.v. administration.
