14 April - EM café!!
Once the Corona-war has ended and we will pose no more risks to one another, we (EM-platform) want to start up the EM-Café !
The idea is that all interested in EM are welcome to share ideas, knowledge, experiences, good or bad, practical tips and tricks, presentations, etc. all on topics closely related to electron microscopy. EM-staff may present new technological developments, you may present and discuss your latest EM-results, etc. No, in between it is not forbidden to talk about the weather, or e.g. a great climbing spot 😉
Of course, the name “EM-café” was not chosen because this event concerns a regular seminar or workshop. No, indeed, it implies that we will do so in a relaxed atmosphere, where we can taste e.g. some beers you brought from that great conference in ‘Beer-country’... and we will foresee these kind of relaxing tranquilizers and make-you-feel-at-easers including non-alcoholic smoothies and other, like typical, advanced EM-food...
More details will follow about location and hour and day. In the meantime, stay healthy and if you can come up with some good ideas about this, always welcome! See you soon!
25 march - Today the news has come! Our EM facility is getting a new FWO-funded 200 kV Cryo-Transmission Electron Microscope!!
With this microscope we will be able to image 3D-ultrastructure of molecules, cells an tissues in their native state. In addition to normal room temperature imaging, we can use this microscope to image in cryo-conditions. The key element is that we will freeze the samples and keep them in their native state, instead of chemical fixation which inherently deviates their state from native.
We will be able to image thicker samples, perform cryo- and RT tomography to reveal ultrastructural details in 3D in cells and tissues. This microscope will give us higher resolution compared with our 3DSEM, which is typically used for e.g. tracking neurons in tissue, complete cells or smaller cellorganelles in 3D.
In short, many biological ultrastructural secrets can be revealed with this microscope and we can't wait to start imaging with it!!
video; tomography of synapse
28 February - Today we had to say goodbye to our great colleague Sergio Gabarre..
Sergio graduated from the University de Zaragoza as a Industrial engineer and holds a Ph.D. in Computational mechanics. In September 2017 he joined the Bioimaging core to start his postdoc on development of correlative light and electron microscopy on our new integrated light and electron microscopy device SECOM.
Almost 2 years you spent inside the small room of the SECOM without a window, working in the dark to prevent bleaching of fluorescent samples, just you and the growing machine. But you did well! A great development was created and because of you we can start using the SECOM to image samples with a light AND an electron microscope in 3D automatically! We can't wait!
But off course with this, the time has come to say our goodbyes; We will miss you and we wish you all the luck in your future plans!!
13 Nov - A new toy for our EM facility arrived: a new “plunge-freezer”; the Leica EM GP2!!!
A plunge-freezer is an instrument to vitrify (= freeze without ice crystal formation) very thin films of mostly suspensions of isolated protein fractions, vesicles, bacteria or cells on EM-support grids. This process stabilizes the ultrastructure of the sample without the need for chemical fixation. The vitrified grids are observed and imaged at -180°C under low electron dose conditions in a transmission electron microscope.
In general, the plunge-freezing process implies the application of a tiny drop of a suspension by a micropipette onto a grid held by a forceps in the plunge-freezer, incubation of the suspension for a few seconds, blotting off the access of suspension and finally plunging the grid into a liquid nitrogen cooled puddle of ethane close to its freezing point.
The Leica EM GP2 replaces our current - mostly manually operated - model, that has served us well, because the new instrument has a number of important advantages. It offers the possibility to parameterize many factors, such as the relative humidity, incubation time, blotting time and number of blots, and several others. As blotting, one of the most critical steps of the process, can be fully automatic, it is expected that this will highly improve reproducibility. In addition, the excellent control of environmental conditions during the process will reduce contamination of the grids by condensing water vapor greatly.
In summary, we are confident that the acquisition of the Leica EM GP2 plunge-freezer will improve the success rate of the freezing process importantly.
4 Oct - NOBEL prize 2017 for cryo-electron microscopy
The Nobel prize for Chemistry 2017 went to 3 investigators (Jacques Dubochet, Joachim Frank and Richard Henderson) whose scientific contributions have led to our current ability to determine the 3D-structure of biomolecules by cryo-electron microscopy.
Conventional preparation techniques for electron microscopy use chemical preparation of biological samples, inevitably influencing the observed ultrastructure to a more or lesser extent. Cryo-EM at the other hand, uses ultra-rapid cooling of a very thin film of a suspension containing the molecules of interest, vitrifying the sample without formation of ice-crystals that could damage the ultrastructure. By applying mathematical algorithms (single particle analysis) to thousands of images of the molecules of interest in many different orientations in the vitrified suspension, the 3D-structure of the molecules is revealed. By recent technological advances in instrumentation it is now possible to obtain 3D-structures at atomic resolution. This information can contribute to solving many questions in biomedical context. See also www.Nobelprize.org.
Whereas we in Leuven use cryo-EM for elucidating ultrastructural features of lipid structures in particular (exosomes, liposomes, etc.) with less demanding resolution requirements, our VIB-colleagues in Brussels (Rouslan Efremov, Structural Biology, VIB@VUB) will install a high-end cryo-electron microscope (expected 2018) for pursuing 3D-structure of biomolecules as described above.