Peers and friends. I need your views on LVEMs (5 or 25kV). I see two manufacturers , however would like to know from customers point. What is the advantage, good , bad and the ugly of LVEMs.
OEMs pl. excuse me , i shall have your comments in different discussion panel.
As far as I understand the big advantage is that the image contrast is enhanced a lot in contrast to usual TEMs with 100kV and more. It is reported that you can also achieve a resolution of 0.14 nm at 15 keV. But low voltage TEMs make only sense to use for biological specimens. On the other hand you have the usual disadvantages of TEM in contrast to SEM (e.g. specimen preparation). So in my opinion I would think about whether I really need such a TEM or whether a good SEM (maybe with STEM detectors) is cheaper and more universally usable.
If you are planning to do a typical biological research (I mean embedded in plastic tissue) you need at least 25 kV; to cut extremely thin sections for 5 kV is very difficult if possible at all.
Hello,
I have seen a low voltage TEM (5kV only!) in operation with my own eyes. The whole electron column is only around 30(!) cm tall and the main advantage is the contrast - thus pathologists buy them.
Sometimes You do not have to stain at all, but the samples are mostly 50 nm and less thick. I will not tell you the company name, since I do not want to advertise it.
You can google Czech republic low voltage TEM instead - they have a nice gallery of what can be done with such a TEM on their webpage.
I personally think, that their TEM is actually a combination of a TEM (with permanent magnet lenses) and a light microscope, but they disagreed with me on this issue.
The disadvantage is, that You "control" the stregth of the "lens" with a small variation of accelerating voltage and that the samples need to be very thin.
So basically, what You save on TEM (it is cheaper than SEM and maybe 3-5 times more expensive than tabletop-SEM depending on the manufacturer and accessories), You spend on a good ultramicrotome (if You do not own one).
And You will also get diffraction (SAED).
- Badges
- Science topic
- Similar topics
- Biological Science
- Molecular Cell Biology
- Culture Cells
- Cell Line