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The structural, morphological, and chemical characterization of samples is of utmost importance for a large number of scientific fields. Furthermore, this characterization very often needs to be performed in three dimensions and at length scales down to the nanometer. Therefore, there is a stringent necessity to develop appropriate instrumentational solutions to fulfill these needs. Here we report on the deployment of magnetic sector secondary ion mass spectrometry (SIMS) on a type of instrument widely used for such nanoscale investigations, namely, focused ion beam (FIB)-scanning electron microscopy (SEM) instruments. First, we present the layout of the FIB-SEM-SIMS instrument and address its performance by using specific test samples. The achieved performance can be summarized as follows: an overall secondary ion beam transmission above 40%, a mass resolving power (

Scientists are using in vitro methods to answer important research questions and implementing strategies to maximize the reliability and human relevance of these methods. One strategy is to replace the use of fetal bovine serum (FBS)-an undefined and variable mixture of biomolecules-in cell culture media with chemically defined or xeno-free medium. In this study, A549 cells, a human lung alveolar-like cell line commonly used in respiratory research, were transitioned from a culture medium containing FBS to media without FBS. A successful transition was determined based on analysis of cell morphology and functionality. Following transition to commercially available CnT-Prime Airway (CELLnTEC) or X-VIVO™ 10 (Lonza) medium, the cells were characterized by microscopic evaluation and calculation of doubling time. Their genotype, morphology, and functionality were assessed by monitoring the expression of gene markers for lung cell types, surfactant production, cytokine release, the presence of multilamellar bodies, and cell viability following sodium dodecyl sulphate exposure. Our results showed that A549 cells successfully transitioned to FBS-free media under submerged and air-liquid-interface conditions. Cells grown in X-VIVO™ 10 medium mimicked cellular characteristics of FBS-supplemented media while those grown in CnT-Prime Airway medium demonstrated characteristics possibly more reflective of normal human alveolar epithelial cells.