【今晚直播】基于数字全息的组织和细胞定量相位成像

报 告 摘 要     

Within the last decade, quantitative phase imaging (QPI) was continuously improved for high resolution label-free quantitative microscopy. Digital holographic microscopy (DHM) is an interferometry-based variant of QPI that typically utilizes a laser as coherent light source. DHM can be modularly integrated into common optical microscopes and provides quantitative phase contrast by detection of specimen induced optical path length changes against the surrounding environment. The reconstruction of digital holograms is performed numerically. Thus, multi focus imaging of specimen and subsequent autofocusing from single captured digital holograms without mechanical focus realignment are achieved. In transmission configuration DHM requires only low light intensities for object illumination and thus minimized the interaction with the investigated sample, which is essential for minimally invasive long-term monitoring of living cell cultures. Moreover, DHM-based phase contrast imaging simplifies automated object tracking and image segmentation for quantification of cell migration and morphology by extraction of absolute biophysical parameters such as cell volume, thickness, or dry mass. In addition, QPI with DHM provides access to the cellular refractive index which is related to the cellular water content, intracellular solute concentrations, and tissue density. After an introduction to QPI with DHM, in an overview, representative applications are presented. First, capabilities of DHM to determine cell motility and growth dynamics during in vitro drug and toxicity testing are illustrated. Then, briefly the potential in histology is demonstrated by quantification of inflammation and nanomaterial induced pathological alterations in ex vivo colon and lung tissue sections. Finally, results from holographic image flow cytometry and perioperative monitoring of living primary human leucocytes after cardiac surgery prospect DHM as a cytometric tool for temporal disease course characterization.