RESUMEN
Over the past decade, the separation efficiency achieved by linear IMS instruments has increased substantially, with state-of-the-art IM technologies, such as the trapped ion mobility (TIMS), the cyclic traveling wave ion mobility (cTWIMS), and the structure for lossless ion manipulation (SLIM) platforms commonly demonstrating resolving powers in excess of 200. However, for complex sample analysis that require front end separation, the achievement of such high resolving power in TIMS is significantly hampered, since the ion mobility range must be broad enough to analyze all the classes of compounds of interest, whereas the IM analysis time must be short enough to cope with the time scale of the preseparation technique employed. In this paper, we introduce the concept of sliding windows in ion mobility (SWIM) for chromatography hyphenated TIMS applications that bypasses the need to use a wide and fixed IM range by using instead narrow and mobile ion mobility windows that adapt to the analytes' ion mobility during chromatographic separation. GC-TIMS-MS analysis of a mixture of 174 standards from several halogenated persistent organic pollutant (POP) classes, including chlorinated and brominated dioxins, biphenyls, and PBDEs, demonstrated that the average IM resolving power could be increased up to 40% when the SWIM mode was used, thereby greatly increasing the method selectivity for the analysis of complex samples.
RESUMEN
A necrose gordurosa da mama é um processo de desintegraçäo de células adiposas, acompanhado de uma reaçäo granulomatosa de intensidade variável. É decorrente do reconhecimento de lipídios extravasados do citoplasma de adipócitos como substâncias estranhas ao meio extracelular. O quadro clínico-radiológico pode ocasionar dificuldades no diagnóstico diferencial com neoplasias mamárias. Neste relato é descrito um caso de necrose gordurosa multinodular mamária sendo enfatizada a importância da citologia por punçäo aspirativa com agulha fina para a confirmaçäo do diagnóstico.