Zell- & Gewebemorphologie

Die Zellmembran funktioniert als Schutzschicht der intrazellulären Inhalte und definiert, zusammen mit dem Zellskelett, die äußere Gestalt der Zelle.
Zusätzlich zu ihrer strukturellen Rolle, ist die Zellmembran auch der Ort, an dem viele wichtige Abläufe geschehen, wie etwa die Zelldifferenzierung, Signalgebung und Interaktion mit dem extrazellulären Raum. Änderungen in der Morphologie der äußeren Membran können Zeichen für geänderte Zellfunktionen, wie Tumorbildung, zellpathogene Interaktionen und gehemmte Zelldifferenzierung sein. Typische Anwendungen beinhalten die Beobachtung von Formänderungen wie Riefen, Poren oder Blasen. In TESCAN UniVac-Modellen mit variablem Kammerinnendruck und zusätzlichem "Water Vapor Inlet" System können empfindliche Proben in nicht dehydriertem Zustand unter variablen Drücken und erhöhter Luftfeuchtigkeit beobachtet werden.
  • Die TESCAN MIRA und MAIA FE-REM sind ideale Instrumente zur Untersuchung zellulärer Strukturen und Gewebestrukturen hei Hoch- und Höchstauflösung.
  • Das TESCAN MAIA UHR FE-REM wurde speziell entwickelt, um ultrahochauflösende Abbildungen bei niedriger Beschleunigungsspannung zu ermöglichen. Dadurch liefert die MAIA besten topographischen Kontrast und detailreiche Abbildungen.
Zell- & Gewebemorphologie

Applikationssbeispiele (in Englisch)

Q-PHASE Live Cell Imaging
Q-PHASE, the multimodal holographic microscope, is a unique instrument for quantitative phase imaging (QPI). The main application of this technique is in live cell imaging where advantages such as no need for labeling, low phototoxicity, easy segmentation, cell dry mass interpretation of measured signal and suitability for long term experiments are used. Q-PHASE is built as a transmitted light microscope in an inverted configuration for easy handling with biological samples. Appropriate conditions for live cells are ensured by the microscope incubator heated to 37°C and low exposures of light for QPI. Moreover, there is no need for specific sample preparation. The cells are just seeded into a suitable observation chamber and examined.
pdf – 1,7 MB
High Resolution Analysis of Thin Foils using the STEM Detector with HADF
Performing scanning transmission electron microscopy (STEM) in a scanning electron microscope (SEM) is a popular technique for laboratories without transmission electron microscopy (TEM) capabilities. The new option for TESCAN STEM detector extends the imaging capabilities by simultaneous acquisition of multiple signals from transmitted and diffracted electrons including bright field, dark field and high angle dark field. The STEM analysis can be further supplemented with transmission EDX or EBSD microanalysis for receiving higher resolution, utilizing the available analytical techniques of the SEM.
pdf – 1,7 MB
Serial Block Face Imaging – 3D Approach to Cell Biology
The facility of integrated Gatan 3View2XP ultra-microtome in the TESCAN microscope offers robust solution to the Serial Block Face Imaging (SBFI). We have performed the structural study of the human stem cell colonies and mouse liver tissues, resulting in their 3D reconstruction.
pdf – 668 kB
STEM Detector in Life Science Applications
Scanning transmission electron microscopy (STEM) has become a highly effective, easy-to-use technique for imaging biological thin sections (lamellae) in SEM. Multiple sample observation, automated stage navigation, and ultra-high resolution imaging make this technique an attractive solution for high-contrast observation of TEM sections with excellent results, and minimal operator’s time.
pdf – 2,4 MB
Q-PHASE Cancer Research
Quantitative Phase Imaging (QPI) provided by Q-PHASE – TESCAN multimodal holographic microscope – allows observation of cells reactions to different treatments without any other added dyes. Combination of QPI with fluorescence provides the possibility to observe cell processes with low phototoxicity and simultaneously verify observed processes using a single instrument. This innovative approach opens interesting opportunities in cancer research. Through experiments, researchers look at how cancer cells behave and try to understand cancer at its deepest levels. Understanding the basic processes of these cells can help researchers figure out what controls cell division and cell death; find out what makes cancer cells spread or metastasize, identify unique characteristics of cancer cells to design newtherapeutic strategies, and, find out why certain cancer cells become resistant to therapy. In some of these experiments, cells taken from tumors of people with cancer are studied.
pdf – 1,3 MB
SEM Observation of Sperm entering the Oocyte
Assisted reproductive technologies are commonly used for treating human infertility, and require handling with gametes. SEM can be used for observing whole oocyte and its surface structures – zona pellucida and plasma membrane – as well for a detailed investigation of gamete interaction during fertilisation (sperm attachment and penetration).
pdf – 2,1 MB
Low Temperature Scanning Electron Microscopy for Life Sciences
Low temperature scanning electron microscopy (Cryo-SEM) has become an established technique for capturing and observing biological samples close to their natural state. It is a method of choice, where the traditional sample preparation (e.g. critical point drying) causes unwanted changes in the sample structure. A Cryo-SEM workflow typically involves sample fixation using either flash-freezing in a liquid nitrogen slush or high-pressure freezing. The frozen samples are then transferred under vacuum to a cryo sputter coater, where they are coated with a conductive layer of metals or carbon. Finally, the samples are inserted into a SEM chamber equipped with a cryo-stage and observed in high vacuum environment.
pdf – 4,8 MB