Micellar electrokinetic capillary chromatography determination of zinc bacitracin and nystatin in animal feed

Abstract

An MEKC procedure was developed for the separation of zinc bacitracin (Zn-BC) and nystatin (NYS) in mixtures and in animal feedstuff. The running buffer was 15 mM borate/19 mM phosphate, pH 8.2, containing 20 mM SDS and 10% v/v methanol. Samples were run at 25 degrees C, the applied voltage was 25 kV, and an additional pressure of 5 mbar was applied. Both analytes were detected by UV simultaneously at 215 nm, Zn-BC alone at 192 and 254 nm, and NYS alone at 305 nm. The method was shown to be specific, accurate (recoveries were 100.0 +/- 0.6% and 100.1 +/- 0.6% for Zn-BC and NYS, respectively), linear over the tested range (correlation coefficients 0.9991 and 0.9994), and precise (RSD below 1.3% for both analytes). The method was applied to determine Zn-BC and NYS as additives in animal feed.

Recent advances in the analysis of antibiotics by CE and CEC

“…Finally, the simultaneous identification and quantitative determination of zinc-bacitracin and nystatin (an antifungal) in spiked animal feedstuffs was carried out using an MEKC method with UV detection. The method was shown to be specific, accurate, linear, and precise, being the robustness suitably evaluated [43]. Figure 5.…”

“…It is used against Gram-positive organisms, especially as an animal feed additive [43]. As it can be observed in Table 6, a MEKC method was reported enabling the rapid separation (about 15 min) of Zn-bacitracin from an antifungal (nystatin) using a phosphateborate buffer (pH 8.2) with 20 mM SDS at 25 kV and 257C (under a running pressure of 5 mbar).…”

“…As it can be observed in Table 6, a MEKC method was reported enabling the rapid separation (about 15 min) of Zn-bacitracin from an antifungal (nystatin) using a phosphateborate buffer (pH 8.2) with 20 mM SDS at 25 kV and 257C (under a running pressure of 5 mbar). Both analytes were detected simultaneously by UV detection at 215 nm while Zn-bacitracin without nystatin was detected at 192 and 254 nm [43].…”

Recent developments in CE and CEC of peptides

“…Enhanced sensitivity of peptide detection at ultralow UV region below 200 nm has been utilized, e.g., in CZE determination of zinc-bacitracin in feedstuff when this peptide antibiotic was detected at 192 nm at low mg/mL level [164]. A universal optical detector based on dual capillary backscatter interferometry with density gradient compensation has been constructed for refractive index measurements in nanoliter volume for microchip CE with sensitivity at the femtomole level [165].…”

“…The concentration LODs of these peptides were in the range 0.31-1.94 mg/mL. CMEKC method with 15 mM borate/19 mM phosphate, pH 8.2, BGE containing 20 mM SDS micellar pseudophase and 10% v/v methanol as organic solvent modifier, was elaborated for separation of zinc bacitracin and nystatin and applied for determination of these antibiotics as additives in animal feedstuff [164].…”