Macrolides sample preparation

In 2008, Carretero et al. described a multi-class method for the analysis of 31 antibacterials (including f)-lactams, macrolides, lincosamides, quinolones, sulfonamides, tetracyclines, nitroimidazoles, and trimethoprim) in meat samples by PLE-LC-MS/MS. Meat samples were homogenized and blended with EDTA-washed sand, then extracted with water by applying 1500 psi (Ib/in. ), at 70°C. One extraction cycle was 10 min. A drawback of the method is the large volumes of extracts (40 ml) obtained, which required evaporation to concentrate the extract volume prior to final analysis. This evaporation step considerably increases the time required for sample preparation. The proposed method has been applied to the analysis of 152 samples of cattle and pig tissues, with the presence of quinolones, tetracyclines, and sulfonamides detected in 15% of the samples, although at concentrations below the MRLs. 

Gonzalez de la Huebra, M.J., Vincent, U. and von Holst, C. (2007) Sample preparation strategy for the simultaneous determination of macrolide antibiotics in animal feeding stuffs by liquid chromatography with electrochemical detection (HPLC-ECD). J. Pham. Biomed. Anal, 43, 1628-1637. 

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