Micellar electrokinetic chromatography with laser induced detection and liquid chromatography tandem mass-spectrometry-based desmosine assays in urine of patients with Chronic Obstructive Pulmonary Disease: a comparative analysis.

Evidences accumulated over the past years that desmosines could be attractive indicators of elastic fibre degradation in Chronic Obstructive Pulmonary Disease have raised substantial interest with the development of reliable assays to measure their concentration in body fluids. It is a firm belief of researchers working in this field that accurate assessment of desmosine concentration would improve the understanding of elastin metabolism disorders and allow these cross-links to become a useful tool in the diagnosis and clinical management of these diseases. From among the variety of techniques available on the market, HPLC; CE and LC-MS have proved to be successful tools for measuring desmosines in biological fluids. However, differences in the analytical performance of methods may hinder the comparability of data, thus limiting the analytical strength and clinical utility of methods themselves. To address the relative contribution of different factors to the exact quantification of desmosines, the full potential of MEKC-LIF and LC-MS, the two systems that better than others offer more selective and sensitive detection for desmosine analysis, was studied on 56 urine samples. The results of this systematic comparative study underline the significant benefits of LC-MS over MEKC-LIF in terms of precision and sensitivity. Nevertheless, MEKC-LIF could be an attractive alternative in routine laboratories lacking the LC-MS instrumentation and skills to run these methods.