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Rairat T, Hsieh CY, Thongpiam W, Chou CC. Pharmacokinetic-pharmacodynamic modelling for the determination of optimal dosing regimen of florfenicol in Nile tilapia (Oreochromis niloticus) at different water temperatures and antimicrobial susceptibility levels. JOURNAL OF FISH DISEASES 2019; 42:1181-1190. [PMID: 31157416 DOI: 10.1111/jfd.13040] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 05/05/2019] [Accepted: 05/07/2019] [Indexed: 06/09/2023]
Abstract
Optimized dosing regimen is key to the effective use of antibacterials and to minimizing drug-related side effects. The current study established a pharmacokinetic-pharmacodynamic (PK-PD) model for the determination of optimal antibacterial dosing regimen in fish taken into consideration the temperature-dependent PK and the pathogen-dependent antimicrobial susceptibility, using florfenicol (FF) in Nile tilapia as an example. The calculated optimal dosages significantly varied by temperature and target MIC levels, ranging from 2.23 (MIC 1 µg/ml at 24°C) to 34.88 mg kg-1 day-1 (MIC 4 µg/ml at 32°C). The appropriateness of the calculated dosages was successfully verified by the in vivo studies. After 5 days of oral administration of the calculated optimal dosage at 24°C, the predicted plasma drug values were in line with the mean observed Cmin(ss) while at 28 and 32°C underestimation of the Cmin(ss) in a dose-dependent manner was observed and likely due to the occurrence of non-linear PK at high dosages. The averaged serum protein binding of FF was 19.1%. Our results demonstrated the appropriateness and clinical applicability of the developed PK-PD approach for the determination of optimal dosing regimens at given temperatures and MICs. Saturation metabolism and PK non-linearity of FF in tilapia warrant further study.
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Affiliation(s)
- Tirawat Rairat
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
| | - Chia-Yu Hsieh
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
| | - Wipavee Thongpiam
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
| | - Chi-Chung Chou
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
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2
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Martin KL, Clapham MO, Davis JL, Baynes RE, Lin Z, Vickroy TW, Riviere JE, Tell LA. Extralabel drug use in small ruminants. J Am Vet Med Assoc 2019; 253:1001-1009. [PMID: 30272520 DOI: 10.2460/javma.253.8.1001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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3
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Activity of florfenicol for Actinobacillus pleuropneumoniae and Pasteurella multocida using standardised versus non-standardised methodology. Vet J 2016; 218:65-70. [DOI: 10.1016/j.tvjl.2016.11.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 09/13/2016] [Accepted: 11/14/2016] [Indexed: 11/22/2022]
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4
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El Badawy S, Amer A, Kamel G, Eldeib K, Constable P. Comparative pharmacokinetics using a microbiological assay and high performance liquid chromatography following intravenous administration of cefquinome in lactating goats with and without experimentally induced Staphylococcus aureus mastitis. Small Rumin Res 2015. [DOI: 10.1016/j.smallrumres.2015.11.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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5
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Pentecost RL, Niehaus AJ, Werle N, Lakritz J. Absorption and disposition of florfenicol after intravenous, intramuscular and subcutaneous dosing in alpacas. Res Vet Sci 2015; 99:199-203. [PMID: 25744433 DOI: 10.1016/j.rvsc.2015.02.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 01/25/2015] [Accepted: 02/09/2015] [Indexed: 11/30/2022]
Abstract
The objectives of this study were to define disposition and systemic availability of florfenicol in alpacas. Administration of 20 mg/kg doses to 8 male alpacas by i.v., i.m. and s.c. routes was performed by randomized, 3-way crossover design. Clearance and steady state volumes (Vdss) after i.v. injection were 5 ml/min/kg and 775 ml/kg respectively. Mean residence time (MRT) and terminal phase half-life (T1/2λz) were 2.8 h and 2 h respectively. Maximum serum concentrations (Cmax) after i.m. were higher than s.c. administration (p = 0.034). After s.c. dosing, T1/2λz and MRT were greater than after i.m. injection (p < 0.001; p = 0.006 respectively). Mean absorption time (MAT) after s.c. dosing was also prolonged (p = 0.006). Fractional absorption of florfenicol after i.m. and s.c. was not different (p > 0.05). Serum florfenicol concentrations remained >1.0 µg/ml for 20 h after i.m. dosing. Differences in rate and extent of florfenicol absorption after extravascular dosing could influence therapeutic outcomes.
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Affiliation(s)
- Rebecca L Pentecost
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Ohio State University, Columbus, OH 43210, USA
| | - Andrew J Niehaus
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Ohio State University, Columbus, OH 43210, USA
| | - Nicholas Werle
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Ohio State University, Columbus, OH 43210, USA
| | - Jeffrey Lakritz
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Ohio State University, Columbus, OH 43210, USA.
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6
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Xu M, Qian M, Zhang H, Ma J, Wang J, Wu H. Simultaneous determination of florfenicol with its metabolite based on modified quick, easy, cheap, effective, rugged, and safe sample pretreatment and evaluation of their degradation behavior in agricultural soils. J Sep Sci 2014; 38:211-7. [PMID: 25395188 DOI: 10.1002/jssc.201400919] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Revised: 10/31/2014] [Accepted: 11/02/2014] [Indexed: 11/08/2022]
Abstract
A simple and simultaneous method for the determination of florfenicol and its metabolite florfenicol amine in agricultural soils using modified quick, easy, cheap, effective, rugged, and safe sample pretreatment and reversed-phase high-performance liquid chromatography with tandem mass spectrometry is presented. Florfenicol and its metabolite florfenicol amine residues in agricultural soils were extracted with alkalized acetonitrile and an aliquot was cleaned up with Si(CH2)3NH(CH2)2NH2 and C18 sorbent, which were powder materials. High-performance liquid chromatography with tandem mass spectrometry was applied to simultaneously determine the level of florfenicol and florfenicol amine in agricultural soils. Excellent linearity was achieved for florfenicol and florfenicol amine over a range of concentrations from 0.1-500 μg/L with coefficients more than 0.99. Average recoveries at four different levels (0.005, 0.05, 0.5, and 5.0 mg/kg) for florfenicol and florfenicol amine ranged from 73.6-94.9% with relative standard deviations of 2.9-12.5%. The limits of detection for florfenicol and florfenicol amine in agricultural soils were 2.0 μg/kg, and the limits of quantification were 6.0 μg/kg. Based on this method, the degradation behavior of florfenicol and its metabolite florfenicol amine in three soils (Nanchang, Hangzhou, and Changchun) under sterilized and native conditions was investigated and the transformation rate of florfenicol amine from florfenicol was evaluated.
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Affiliation(s)
- Mingfei Xu
- Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences; State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, MOA Key Laboratory for Pesticide Residue Detection, Hangzhou, China
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7
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Pérez R, Palma C, Drápela C, Sepulveda M, Espinoza A, Peñailillo AK. Pharmacokinetics of florfenicol after intravenous administration in Escherichia coli lipopolysaccharide-induced endotoxaemic sheep. J Vet Pharmacol Ther 2014; 38:144-9. [PMID: 25229993 DOI: 10.1111/jvp.12160] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 08/02/2014] [Indexed: 11/29/2022]
Abstract
Experiments in different animal species have shown that febrile conditions, induced by Escherichia coli lipopolysaccharide (LPS), may alter the pharmacokinetic properties of drugs. The objective was to study the effects of a LPS-induced acute-phase response (APR) model on plasma pharmacokinetics of florfenicol (FFC) after its intravenous administration in sheep. Six adult clinically healthy Suffolk Down sheep, 8 months old and 35.5 ± 2.2 kg in body weight (bw), were distributed through a crossover factorial 2 × 2 design, with 4 weeks of washout. Pairs of sheep similar in body weight were assigned to experimental groups: Group 1 (LPS) was treated with three intravenous doses of 1 μg/kg bw of E. coli LPS before FFC treatment. Group 2 (control) was treated with an equivalent volume of saline solution (SS) at similar intervals as LPS. At 24 h after the first injection of LPS or SS, an intravenous bolus of 20 mg/kg bw of FFC was administered. Blood samples (5 mL) were collected before drug administration and at different times between 0.05 and 48.0 h after treatment. FFC plasma concentrations were determined by liquid chromatography. A noncompartmental pharmacokinetic model was used for data analysis, and data were compared using a Mann-Whitney U-test. The mean values of AUC0-∞ in the endotoxaemic sheep (105.9 ± 14.3 μg·h/mL) were significantly higher (P < 0.05) than values observed in healthy sheep (78.4 ± 5.2 μg·h/mL). The total mean plasma clearance (CLT ) decreased from 257.7 ± 16.9 mL·h/kg in the control group to 198.2 ± 24.1 mL·h/kg in LPS-treated sheep. A significant increase (P < 0.05) in the terminal half-life was observed in the endotoxaemic sheep (16.9 ± 3.8 h) compared to the values observed in healthy sheep (10.4 ± 3.2 h). In conclusion, the APR induced by the intravenous administration of E. coli LPS in sheep produces higher plasma concentrations of FFC due to a decrease in the total body clearance of the drug.
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Affiliation(s)
- R Pérez
- Laboratorio de Farmacología, Departamento de Ciencias Clínicas, Facultad de Ciencias Veterinarias, Universidad de Concepción, Chillán, Chile
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8
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PALMA C, RAMÍREZ J, BENAVENTE A, CAZANGA V, VENEGAS M, PÉREZ R. Pharmacokinetics of florfenicol and florfenicol-amine after intravenous administration in sheep. J Vet Pharmacol Ther 2011; 35:508-11. [DOI: 10.1111/j.1365-2885.2011.01357.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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9
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Lim JH, Lee HG, Kim TW, Song IB, Kim MS, Hwang YH, Park BK, Yun HI. Comparison of Microbiological Assay and High-Performance Liquid Chromatography/Mass Spectrometry for the Pharmacokinetics of Cefquinome in Pigs. ACTA ACUST UNITED AC 2011. [DOI: 10.3923/aj.2011.374.377] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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10
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LIU N, GUO M, MO F, SUN YH, YUAN Z, CAO LH, JIANG SX. Involvement of P-glycoprotein and cytochrome P450 3A in the metabolism of florfenicol of rabbits. J Vet Pharmacol Ther 2011; 35:202-5. [DOI: 10.1111/j.1365-2885.2011.01310.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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11
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Effect of three anthelmentics on disposition kinetics of florfenicol in goats. Food Chem Toxicol 2010; 48:3340-4. [DOI: 10.1016/j.fct.2010.08.039] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Revised: 08/08/2010] [Accepted: 08/20/2010] [Indexed: 11/18/2022]
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12
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Verma S, Ahmad AH, Rahal A, Singh KP. Pharmacokinetics of Florfenicol Following Single Dose Intravenous and Intramuscular Administration in Goats. JOURNAL OF APPLIED ANIMAL RESEARCH 2009. [DOI: 10.1080/09712119.2009.9707039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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13
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Pharmacokinetics of florfenicol after intravenous and intramuscular administration in New Zealand White rabbits. Res Vet Sci 2009; 87:102-5. [DOI: 10.1016/j.rvsc.2008.10.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2008] [Revised: 10/06/2008] [Accepted: 10/22/2008] [Indexed: 11/21/2022]
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14
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Park BK, Lim JH, Kim MS, Hwang YH, Yun HI. Pharmacokinetics of florfenicol and its metabolite, florfenicol amine, in dogs. Res Vet Sci 2008; 84:85-9. [PMID: 17570454 DOI: 10.1016/j.rvsc.2007.04.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2005] [Revised: 03/07/2007] [Accepted: 04/11/2007] [Indexed: 11/18/2022]
Abstract
A study on the bioavailability and pharmacokinetics of florfenicol was conducted in six healthy dogs following a single intravenous (i.v.) or oral (p.o.) dose of 20 mg kg(-1) body weight (b.w.). Florfenicol concentrations in serum were determined by a high-performance liquid chromatography/mass spectrometry. Plasma concentration-time data after p.o. or i.v. administration were analyzed by a non-compartmental analysis. Following i.v. injection, the total body clearance was 1.03 (0.49) L kg(-1)h(-1) and the volume of distribution at steady-state was 1.45 (0.82) L kg(-1). Florfenicol was rapidly distributed and eliminated following i.v. injection with 1.11 (0.94)h of the elimination half-life. After oral administration, the calculated mean C(max) values (6.18 microg ml(-1)) were reached at 0.94 h in dogs. The elimination half-life of florfenicol was 1.24 (0.64) h and the absolute bioavailability (F) was achieved 95.43 (11.60)% after oral administration of florfenicol. Florfenicol amine, the major metabolite of florfenicol, was detected in all dogs after i.v. and p.o. administrations.
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Affiliation(s)
- Byung-Kwon Park
- Division of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Chungnam National University, Daejeon, Republic of Korea
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15
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Park BK, Lim JH, Kim MS, Hwang YH, Yun HI. Pharmacokinetics of florfenicol and its major metabolite, florfenicol amine, in rabbits. J Vet Pharmacol Ther 2007; 30:32-6. [PMID: 17217398 DOI: 10.1111/j.1365-2885.2007.00809.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The pharmacokinetics of florfenicol and its active metabolite florfenicol amine were investigated in rabbits after a single intravenous (i.v.) and oral (p.o.) administration of florfenicol at 20 mg/kg bodyweight. The plasma concentrations of florfenicol and florfenicol amine were determined simultaneously by an LC/MS method. After i.v. injection, the terminal half-life (t(1/2lambdaz)), steady-state volume of distribution, total body clearance and mean residence time of florfenicol were 0.90 +/- 0.20 h, 0.94 +/- 0.19 L/kg, 0.63 +/- 0.06 L/h/kg and 1.50 +/- 0.34 h respectively. The peak concentrations (C(max)) of florfenicol (7.96 +/- 2.75 microg/mL) after p.o. administration were observed at 0.90 +/- 0.38 h. The t(1/2lambdaz) and p.o. bioavailability of florfenicol were 1.42 +/- 0.56 h and 76.23 +/- 12.02% respectively. Florfenicol amine was detected in all rabbits after i.v. and p.o. administration. After i.v. and p.o. administration of florfenicol, the observed Cmax values of florfenicol amine (5.06 +/- 1.79 and 3.38 +/- 0.97 microg/mL) were reached at 0.88 +/- 0.78 and 2.10 +/- 1.08 h respectively. Florfenicol amine was eliminated with an elimination half-life of 1.84 +/- 0.17 and 2.35 +/- 0.94 h after i.v. and p.o. administration respectively.
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Affiliation(s)
- B-K Park
- Division of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Chungnam National University, Daejeon, Korea
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16
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Tuttle AD, Papich MG, Wolfe BA. Bone marrow hypoplasia secondary to florfenicol toxicity in a Thomson's gazelle (Gazella thomsonii). J Vet Pharmacol Ther 2006; 29:317-9. [PMID: 16846470 DOI: 10.1111/j.1365-2885.2006.00741.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- A D Tuttle
- Department of Clinical Sciences, North Carolina State University, Raleigh, NC 27606, USA.
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Kowalski P, Konieczna L, Chmielewska A, Oledzka I, Plenis A, Bieniecki M, Lamparczyk H. Comparative evaluation between capillary electrophoresis and high-performance liquid chromatography for the analysis of florfenicol in plasma. J Pharm Biomed Anal 2005; 39:983-9. [PMID: 16084049 DOI: 10.1016/j.jpba.2005.05.032] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2005] [Revised: 05/16/2005] [Accepted: 05/17/2005] [Indexed: 11/19/2022]
Abstract
A capillary electrophoresis (CE) and a reversed phase high-performance liquid chromatography (RP-HPLC) method with UV detection have been developed for florfenicol analysis in plasma samples. The suitabilities of both methods for quantitative determination of florfenicol were approved through validation specification, such as linearity, precision, selectivity, accuracy, limit of detection and quantification. The capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC) assay were compared by analyzing a series of plasma samples containing florfenicol in different concentrations using the two methods. The extraction procedure is simple and no gradient elution or derivatization is required. Furthermore, the analysis time of the CE method is two times shorter than the respective parameter in HPLC and solvent consumptions is considerably lower. The calibration curve were linear to at least 0.05-10 microg/ml (r = 0.9998) and 0.1-10 microg/ml (r = 0.9998) for CE and HPLC, respectively. The separation efficiency are good for both methods. The detection limits for florfenicol were 0.015 microg/ml with CE and 0.03 microg/ml with HPLC and CE method gave lower value, even though UV detector was applied in the both cases. The both methods were selective, robust and reliable quantification of florfenicol and can be useful for clinical and biomedical investigations.
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Affiliation(s)
- Piotr Kowalski
- Medical University of Gdańsk, Faculty of Pharmacy, Hallera 107, PL-80-416 Gdańsk, Poland.
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Hillaert S, Van den Bossche W. Optimization and validation of a micellar electrokinetic chromatographic method for the analysis of florfenicol. J Pharm Biomed Anal 2004; 36:437-40. [PMID: 15522515 DOI: 10.1016/j.jpba.2004.07.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2004] [Revised: 07/07/2004] [Accepted: 07/08/2004] [Indexed: 11/29/2022]
Abstract
We have optimized a micellar electrokinetic capillary chromatographic method for the separation of florfenicol and florfenicol amine, its degradation product. The separation was carried out using a 50mM sodium borate buffer (pH 9.0) containing 25mM of sodium dodecyl sulphate. The method selectivity was proven by the simultaneous separation of florfenicol and two structural antibiotics, chloramphenicol and thiamphenicol. The same system can also be applied for the quantitative determination of these antibiotics. The method was then validated regarding linearity, precision and accuracy.
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Affiliation(s)
- S Hillaert
- Laboratory of Pharmaceutical Chemistry and Drug Analysis, Department of Pharmaceutical Analysis, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, B-9000 Ghent, Belgium.
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Lane VM, Villarroel A, Wetzlich SE, Wetzlich S, Clifford A, Taylor I, Craigmill AL. Intravenous and subcutaneous pharmacokinetics of florfenicol in sheep. J Vet Pharmacol Ther 2004; 27:191-6. [PMID: 15305846 DOI: 10.1111/j.1365-2885.2004.00580.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Pharmacokinetic parameters of florfenicol were determined in 10 adult sheep (five wethers and five ewes) after a single 40 mg/kg intravenous (i.v.) dose, and three daily subcutaneous (s.c.) doses of 40 mg/kg of a commercial preparation (Nuflor((R))). The concentration of florfenicol in serum samples was assayed using a proprietary HPLC assay method, and pharmacokinetic parameters derived for individual animal data by each route using compartmental and noncompartmental approaches. Two animals (one male and one female) were excluded due to observed i.v. dosing problems, and a biexponential model was found to fit the i.v. data well for six of the other eight animals. Data from two males showed prolonged low concentrations of florfenicol in serum and were better fit by a three-compartment model. The mean +/- SD for the half-lives of the distribution and elimination phases for the six sheep best fit with a two-compartment model were 0.069 +/- 0.018 and 1.01 +/- 0.09 h respectively, and for the V(d(ss)) and clearances were 0.503 +/- 0.035 L/kg and 366 +/- 53 mL/h/kg respectively. The data collected during the s.c. multiple dose study were analyzed using noncompartmental methods only. The bioavailability (F%) after s.c. dosing was calculated in three ways to compare estimation methods as steady-state had not been reached and single dose s.c. data were not obtained past 24 h. Using the AUC(0--24) and AUC(0--> infinity ) from the first dose, the F% values averaged 27 and 40% respectively. Using the AUC(0--> infinity ) for all doses, the F% was 65%. Calculations of the mean time during which the serum concentration exceeded 0.5 and 1.0 microg/mL were 105 +/- 3.9 and 74.7 +/- 12.2 h respectively.
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Affiliation(s)
- V M Lane
- Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA, USA
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Shen J, Li X, Jiang H, Hsu WH, Jianzhong S, Xiubo L, Haiyang J, Walter HH. Bioavailability and pharmacokinetics of florfenicol in healthy sheep*. J Vet Pharmacol Ther 2004; 27:163-8. [PMID: 15189302 DOI: 10.1111/j.1365-2885.2004.00574.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A study on bioavailability and pharmacokinetics of florfenicol was conducted in 20 crossbred healthy sheep following a single intravenous (i.v.) and intramuscular (i.m.) doses of 20 and 30 mg/kg body weight (b.w.). Florfenicol concentrations in serum were determined by a validated high-performance liquid chromatography method with UV detection at a wavelength of 223 nm in which serum samples were spiked with chloramphenicol as internal standard. Serum concentration-time data after i.v. administration were best described by a three-compartment open model with values for the distribution half-lives (T(1/2alpha)) 1.51 +/- 0.06 and 1.59 +/- 0.10 h, elimination half-lives (T(1/2beta)) 18.83 +/- 6.76 and 18.71 +/- 1.85 h, total body clearance (Cl(B)) 0.26 +/- 0.03 and 0.25 +/- 0.01 L/kg/h, volume of distribution at steady-state (V(d(ss))) 1.86 +/- 0.11 and 1.71 +/- 0.20 L/kg, area under curve (AUC) 76.31 +/- 9.17 and 119.21 +/- 2.05 microg.h/mL after i.v. injections of 20 and 30 mg/kg b.w. respectively. Serum concentration-time data after i.m. administration were adequately described by a one-compartment open model. The pharmacokinetic parameters were distribution half-lives (T(1/2k(a) )) 0.27 +/- 0.03 and 0.25 +/- 0.09 h, elimination half-lives (T(1/2k(e) )) 10.34 +/- 1.11 and 9.57 +/- 2.84 h, maximum concentrations (C(max)) 4.13 +/- 0.29 and 7.04 +/- 1.61 microg/mL, area under curve (AUC) 67.95 +/- 9.61 and 101.95 +/- 8.92 microg.h/mL, bioavailability (F) 89.04% and 85.52% after i.m. injections of 20 and 30 mg/kg b.w. respectively.
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Affiliation(s)
- Jianzhong Shen
- Department of Pharmacology and Toxicology, College of Veterinary Medicine, China Agriculture University, Beijing, China
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21
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Ali BH, Al-Qarawi AA, Hashaad M. Comparative plasma pharmacokinetics and tolerance of florfenicol following intramuscular and intravenous administration to camels, sheep and goats. Vet Res Commun 2003; 27:475-83. [PMID: 14582746 DOI: 10.1023/a:1025741724701] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Florfenicol, a monofluorinated analogue of thiamphenicol, has a broad antibacterial spectrum. The pharmacokinetics of florfenicol was studied following a single intravenous (i.v.) or intramuscular (i.m.) injection at a dose of 20 mg/kg body weight in healthy male camels, sheep and goats. The concentration of florfenicol in plasma was determined using a microbiological assay. Pharmacokinetic analysis was performed using a two-compartment open model. Following i.m. administration, the maximum plasma concentration of florfenicol (Cmax) reached in camels, sheep and goats was 0.84 +/- 0.08, 1.04 +/- 0.10 and 1.21 +/- 0.10 microg/ml, respectively, the the time required to reach Cmax (t(max)) in the same three respective species was 1.51 +/- 0.14, 1.44 +/- 0.10 and 1.21 +/- 0.10 h. The terminal half-life (t(1/2)beta) and the fraction of the drug absorbed (F%) in camels, sheep and goats were 151.3 +/- 16.33, 137.0 +/- 12.16 and 127.4 +/- 11.0 min, and 69.20% +/- 7.8% , 65.82% +/- 6.7% and 60.88% +/- 5.9%, respectively. The MRT in the same three respective species was 4.01 +/- 0.45, 3.42 +/- 0.39 and 2.98 +/- 0.32 h. Following i.v. administration, the terminal half-life (t(1/2)beta) and total body clearance (Clbeta) in camels, sheep and goats were 89.5 +/- 9.2, 78.8 +/- 8.3 and 71.1 +/- 8.9 min and 0.33 +/- 0.04, 0.30 +/- 0.03 and 0.27 +/- 0.03 L/h per kg, respectively. The area under the curve (AUC(0-infinity)) and the mean residence time (MRT) in the same three respective species were 60.61 +/- 6.98, 62.45 +/- 6.56 and 74.07 +/- 7.85 microg/ml per h, and 2.71 +/- 0.31, 2.34 +/- 0.25 and 2.11 +/- 0.23 h. These data suggest that sheep and goats absorb and clear florfenicol to a broadly similar extent, but the rate and extent of absorption of the drug tends to be higher in camels. Drug treatment caused no clinically overt adverse effects. Plasma enzyme activities and metabolites indicative of hepatic and renal functions measured 1, 2, 4 and 7 days following the drug treatment were within the normal range, indicating that the drug is safe at the dose used.
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Affiliation(s)
- B H Ali
- Department of Veterinary Medicine, King Saud University, Al Gaseem Branch, Buraydah, Saudi Arabia.
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