A Novel Depsipeptide Produced by Paenibacillus alvei 32 Isolated from a Cystic fibrosis Patient.

The important viscosity of the respiratory tract mucus of Cystic fibrosis (CF) patients impairs the mucociliary transport system and allows the growth of numerous micro-organisms. Among them, Pseudomonas aeruginosa and Staphylococcus aureus are known to be responsible for pulmonary infections. We imagined that CF microflora could also harbour micro-organisms naturally equipped to compete with these pathogens.

Characterization of impurities in josamycin using dual liquid chromatography combined with mass spectrometry.

The European Pharmacopoeia (Ph. Eur.) prescribes a selective and sensitive liquid chromatography/ultraviolet (LC-UV) method for the separation of the 16-membered ring macrolide josamycin and its related compounds.

Optimization and validation of liquid chromatography and headspace-gas chromatography based methods for the quantitative determination of capsaicinoids, salicylic acid, glycol monosalicylate, methyl salicylate, ethyl salicylate, camphor and l-menthol in a topical formulation.

Capsaicinoids, salicylic acid, methyl and ethyl salicylate, glycol monosalicylate, camphor and l-menthol are widely used in topical formulations to relieve local pain. For each separate compound or simple mixtures, quantitative analysis methods are reported. However, for a mixture containing all above mentioned active compounds, no assay methods were found.

Identification of impurities in polymyxin B and colistin bulk sample using liquid chromatography coupled to mass spectrometry.

The European Pharmacopoeia (Ph. Eur.) describes liquid chromatography-ultraviolet (LC-UV) methods using C(18) stationary phases for the analysis of polymyxin B and colistin.

Combination of a liquid chromatography-ultraviolet method with a non-volatile eluent, peak trapping and a liquid chromatography-mass spectrometry method with a volatile eluent to characterise erythromycin related substances.

The selectivity and sensitivity obtained with volatile liquid chromatographic (LC) methods are often inferior compared to non-volatile ones. However, the buffers often used in the non-volatile system are incompatible to mass spectrometry (MS). So, the characterisation of unknown peaks in a non-volatile system, based on data obtained from a volatile LC-MS method, is problematic.