Determination Of Thiamphenicol Research Articles

UPLC-MS/MS determination of thiamphenicol in human plasma and its application to a pharmacokinetic study.

A sensitive and rapid ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed to determine thiamphenicol (TAP) in human plasma using chlorzoxazone as the internal standard (IS). Sample preparation was accomplished through a liquid-liquid extraction procedure with ethyl acetate to precipitation of plasma protein, and to a 0.1 mL plasma sample. The analyte and IS were separated on an Acquity UPLC BEH C18 column (2.1 mm × 50 mm, 1.7 μm) with the mobile phase of acetonitrile and 1% formic acid in water with gradient elution at a flow rate of 0.40 mL/min. The detection was performed on a triple quadrupole tandem mass spectrometer equipped with electrospray ionization (ESI) by multiple reactions monitoring (MRM) of the transitions at m/z 354.3→185.1 for TAP and m/z 168.1→132.1 for IS. The linearity of this method was found to be within the concentration range of 10-8000 ng/mL with a lower limit of quantification of 10 ng/mL. Only 1.5 min was needed for an analytical run. The method herein described was superior to previous methods and was successfully applied to the pharmacokinetic study of TAP in healthy Chinese volunteers after oral administration.

Determination of Thiamphenicol in Honey by Dispersive Liquid--Liquid Microextraction with High-Performance Liquid Chromatography

Dispersive liquid-liquid microextraction (DLLME) coupled with high-performance liquid chromatography-variable wavelength detector (HPLC-VWD) was developed for extraction and determination of thiamphenicol (THA) in honey. A mixture of extraction solvent (30 microL 1,1,2,2-tetrachloroethane) and dispersive solvent (1.0 mL of acetonitrile) was rapidly injected into 5.00 mL sample solution for the formation of cloudy solution. The analyte in the sample was extracted into the fine droplets of C(2)H(2)Cl(4). After extraction, phase separation was performed by centrifugation, and the enriched analyte in the sedimented phase was determined by HPLC-VWD. Some important parameters, such as the kind and volume of extraction solvent and dispersive solvent, extraction time, sample solution pH, sample volume, and salt effect, were investigated and optimized. Under the optimum extraction condition, the method yielded a linear calibration curve in the concentration range from 3 to 2000 microg/kg for target analyte. The enrichment factors for THA was 87.9, and the limit of detection (S/N = 3) was 0.1 microg/kg. The relative standard deviation for the extraction of 10 microg/kg of THA was 6.2% (n = 6). The main advantages of DLLME-HPLC method are simplicity of operation, rapidity, low cost, high enrichment factor, high recovery, good repeatability, and extraction solvent volume at the microL level. Honey samples were successfully analyzed using the proposed method.

Determination of thiamphenicol in human plasma by micellar electrokinetic capillary chromatography.

A micellar electrokinetic chromatographic method is described for the determination of thiamphenicol in human plasma. The plasma sample was basified by adding K2HPO4 and was then extracted with ethyl acetate. After the solvent was evaporated, the residue was reconstituted in water. Approximately 40 nl of the solution were injected hydrodynamically. The running buffer was 20 mM borate (pH 9.2) containing 40 mM sodium dodecyl sulfate and 10% acetonitrile. The applied voltage was 18 kV and the detector wavelength was set at 195 nm. On-column sample stacking was achieved during the analysis to enhance the sensitivity; the limit of quantitation was 0.1 microg/ml. Linearity was over the range of 0.2 to 10 microg/ml. Recovery was 93.7+/-3.3%, the intra-day precision and accuracy was 99.6+/-2.8%; the inter-day precision and accuracy was 98.4+/-3.4%. The concentration of thiamphenicol in human plasma from eight volunteers was measured after administering thiamphenicol capsules orally.

Liquid Chromatographic Analysis of Thiamphenicol Residues in Milk

Abstract The present paper describes a modified high-performance liquid chromatographic (HPLC) method for the determination of thiamphenicol (THA) residues in spiked milk at levels as low as 30 ppb. Milk spiked with THA was extracted with ethyl acetate. Following addition of hexane, the extract was cleaned up with a silica cartridge. Analysis was performed on a reversed-phase C18, 5 μm, column using water-methanol (70:30) as mobile phase. Recovery was found to range from 68.0 to 90.0 % and precision data suggested that relative standard deviation ranged from 7 to 9.4 %.

Procedure for Liquid Chromatographic Determination of Thiamphenicol in Bovine Serum and Milk

Abstract We describe a method for measuring thiamphenicol (TP) by high-performance liquid chromatography (HPLC). The assay involves a simple extraction procedure using Extrelut-3 with ethyl acetate, evaporation of the extract, and redissolution in 40% acetonitrile. Wakosil-II 5C18 HG is used as a stationary phase with an eluting solvent of acetonitrile/water (40/60 by vol). TP is eluted from the column in about 2.3 min and is well separated from the other components present in serum or milk. Absorption of the eluent at 224 nm is monitored and measured. After extraction from a 1-ml sample, the antibiotic can be analyzed within 30 min. The within-day recoveries for bovine serum and milk spiked with 1 ppm TP were 92.9% and 93.5%, respectively, with coefficients of variation of 3.18% and 3.21%, respectively. The between-day recoveries for the 1 ppm samples were 91.9% and 92.3%, respectively, with coefficients of variation of 4.50% and 4.40%, respectively. The method is suitable for rapid and specific analysis...

High Performance Liquid Chromatographic Analysis of Residues of Thiampenicol in Beef Muscle

Abstract The present paper describes a high-performance liquid chromatographic (HPLC) method for the determination of thiamphenicol (THA) residues in spiked meat at levels as low as 10 ppb. Meat spiked with THA was extracted twice with ethyl acetate. The extract was washed with 4% w/v NaCl solution saturated with ethyl acetate and then was evaporated to dryness. The oily residue was dissolved in 1 ml of a mixture of n-hexane-chloroform (1:1, v/v). Then 1 ml of water was added to the tube and after stirring and centrifugation, an aliquot of the upper layer was analyzed on a reversed-phase C18, 5 μ column. Recovery was found to range from 64.8% to 75.5%. The linearity, in the range examined, was good (r = 0.995, 5–80 ppb). Precision data suggested relative standard deviation ranged from 2.1 to 3.9%.

Determination of Thiamphenicol in Bovine Plasma by Liquid Chromatography

A liquid chromatographic method is described for the measurement of thiamphenicol in bovine plasma. The plasma (1 mL) is extracted with ethyl acetate. After the solvent is evaporated under a stream of nitrogen, the residue is reconstituted in methanol-water and analyzed by reverse-phase liquid chromatography with UV detection at 224 nm. The intra-day recoveries for bovine plasma spiked with 5 and 50 micrograms/mL of thiamphenicol were 102 and 101%, respectively, with coefficients of variation of 2.40 and 0.28%, respectively. The interday recoveries for the 5 and 50 micrograms/mL samples were 103 and 101%, respectively, with coefficients of variation of 3.40 and 0.94%, respectively. The sensitivity of the method allows quantitation to at least the 100 ng/mL level.

Determination of Thiamphenicol in Serum and Cerebrospinal Fluid with High-Pressure Liquid Chromatography

Abstract A procedure for quantitation of thiamphenicol in serum and cerebrospinal fluid was developed using high-pressure liquid chromatography. The drug was extracted from biological samples with methanol and separated by reverse-phase high-pressure liquid chromatography. Detection and subsequent quantitation were performed at 254 nm by on-line ultraviolet spectrophotometry. After the intramuscular administration of a single dose of 1 g of thiamphenicol to a patient, a poor transmission of the drug across the hematoencephalic barrier was demonstrated by this assay.

Determination of thiamphenicol in biological fluids by gas chromatography

Determination of thiamphenicol in biological fluids by gas chromatography