HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC ANALYSIS OF MUPIROCIN IN POLYETHYLENE GLYCOL-400 AND GLYCOL-3350 USING DUAL ULTRAVIOLET AND EVAPORATIVE LIGHT-SCATTERING DETECTION

Using dual detection with UV and evaporative light scattering detector s, a gradient LC-MS-compatible method was successfully developed for t he separation and identification of impurity and degradates in mupiroc in in a complex matrix containing 98% (w/w) of polyethylene glycol (PE G) 400 and PEG 3350. The method enabled the eluent containing the PEGs to be diverted before it entered and contaminated the mass spectromet er source. The impurity was identified as Pseudomonic D, and the degra dates were rearrangement product I and rearrangement product II, respe ctively.