Journal of the Brazilian Chemical Society
On-line version ISSN 1678-4790
SILVA JR., Luiz Severo et al. Chromatographic determination of riboflavin in the presence of tetracyclines in skimmed and full cream milk using fluorescence detection. J. Braz. Chem. Soc. [online]. 2005, vol.16, n.6a, pp. 1174-1178. ISSN 1678-4790. http://dx.doi.org/10.1590/S0103-50532005000700013.
An easy and simple chromatographic method for the determination of riboflavin in bovine milk in the presence of tetracyclines was established. For this, the proteins were precipitated with trichloroacetic acid and the separation was carried out by reversed-phase HPLC with fluorescence detection. A C8 column was used with isocratic flow using a mobile phase consisting of 0.1 mol L-1 sodium acetate, 35 mmol L-1calcium chloride and 25 mmol L-1 EDTA : methanol (65:35 v/v). The method was validated by means of the following parameters: linearity (0.9980), linear range (0.50 - 1.30 µg mL-1), intra- and inter-assay precision (RSD < 0.5%), accuracy (recovery 92%), and detection and quantitation limits (0.75 µg mL-1 and 0.22 µg mL-1, respectively). The method was applied for analysis of full cream and skimmed milk, showing robustness in the presence of tetracyclines, and when compared with a spectrofluorimetric method showed no significant difference (p < 0.05) between the results obtained.
Keywords : riboflavin; milk; tetracyclines.