Simultaneous Determination of Chloramphenicol, Florfenicol, and Thiamphenicol Residues in Milk by Gas Chromatography with Electron Capture Detection

Abstract

A gas chromatographic (GC) method is described for determining residues of chloramphenicol (CAP), florfenicol (FF), and thiamphenicol (TAP) in raw milk, with meta-nitrochloramphenicol (mCAP) as internal standard. Milk is extracted with acetonitrile, centrifuged, evaporated, reconstituted in water, and passed through a C18 solid-phase extraction (SPE) column. The SPE column is eluted with 60℅ methanol, and then the eluate is evaporated and derivatized with Sylon BFT {N,0-bis(trimethylsilyl) trifluoroacetamide [BSTFA]-trimethylchlorosilane [TMCS], 99 + 1}. After derivatization, toluene is added directly to the sample, followed by water, to quench the derivatization process. After centrifugation, the organic layer is carefully removed. Analytes are determined by GC with electron capture detection (ECD). Milk was fortified with fenicols (the collective name for CAP, FF, and TAP) at 5,10, 20, 40 and 80 ng/mL (target level = 10 ng/mL). Overall recoveries were 92,100, and 104℅ for CAP, FF, and TAP, respectively. Overall interassay (betweenday) variabilities were 6.1, 6.7, and 6.0℅ for CAP, FF, and TAP, respectively. Raw milk samples containing incurred residues of FF were also analyzed.

Pharmacokinetics of chloramphenicol in carp (Cyprinus carpio L.) after drug administration

“…Several analytical methods have been developed for the determination of CAP in biological materials, such as gas chromatography with electron capture detection (GC-ECD), gas chromatography mass spectrometry (GC-MS) (Van Ginkel, van Rossum, Zoontjes, van Blitterswijk, Ellen, van der Heeft, de Jong & Zomer 1990;Nagata & Oka 1996;Pfenning, Madson, Roybal, Turnipseed, Gonzalas, Hurlbut & Salmon 1998), liquid chromatography with photodiode array detection (LC-DAD) and liquid chromatography mass spectrometry (LC-MS) (Kennedy, McCracken, Cannavan & Hewitt 1998;Corcia & Nazzari 2002;Li, Chung-Wang & Shih 2002;Mottier, Parisod, Gremaud, Guy & Stadler 2003). However, these methods were used to measure CAP in ¢nished products.…”

Depletion of florfenicol in lactating dairy cows after intramammary and subcutaneous administration

“…The HPLC procedure used for screening was not amenable to processing the large numbers of samples that had been collected for pharmacokinetic analyses. Hence, a gas-liquid chromatographic (GC) procedure with electron capture detection based on the method described by Pfenning et al (Pfenning et al, 1998(Pfenning et al, , 2000 was used for all subsequent analyses of the plasma samples and the reanalyses of all the milk samples.…”

Differential Spectrophotometric Method for Determination of Florfenicol

“…It is also used in aquaculture and is licensed for use in the United States for the control of enteric septicemia in catfish 2 . [3][4][5][6] , which have been applied mainly for its analysis in biological fluids. Recently, we developed simple and accurate methods for its analysis and stability studies in pharmaceutical dosage form 7,8 .…”