As technology has advanced, the ability and applications attached to being able to see and
understand biological processes at the microscopic level has become increasingly important.
However, while microscopes in themselves are nothing new, the challenge has always been
in finding an effective way to translate what appears through the lens into a detailed and
useful on-screen image.
This has led to the development of a host of imaging methods that specialize in high
resolution, large depth field, and 3-D or even 4-D representation. These allow researchers
and medical practitioners to conduct non-invasive, non-destructive, dynamic biomedical tests
Large field depth combined with optimum magnification
In a conventional optical microscope, researchers have to make an either/or choice
between these two parameters. This means it is not possible to obtain clear images of
objects if they are located at different depths. A scanning electron microscope (SEM)
provides the solution to this problem.
The SEM scans the sample surface using a thin electronic beam. Electrons are passed to a
detector, and the signals are then transformed into 3D images using specialist visualization
software from the likes of Bitplane. Take a look at their website to find out more about how
the software works.
This is an integrated technology, which combines optical technology and digital image
analysis. This cutting-edge branch of microscopy can obtain incredible field depth, perfect
detail, and provides better color clarity than is typically the case when using an electron
microscope. The confocal microscope essentially seeks out each of the samples under
examination at different depth levels assembles a collection of images, then transfers these
to a computer, where the data is analyzed and integrated using proprietary processing
software to provide a clear and high-quality image.
The technology can be used to continuously scan living cells and biopsy samples one layer
at a time, in order to obtain images at a variety of depths. Used in combination with
reconstruction algorithms, it provides three-dimensional images that observe or access
chromosomes, cell membrane, and organelles.
In vivo applications
Being able to observe and monitor living cells can be of huge benefit in the medical research
arena, but has historically been a very difficult thing to achieve. A number of research
organisations have focused on this area in a bid to bring a quantum leap in medical
Fluorescence resonance energy transfer is a prime example. Here, specific fluorescence
probes are used to label the material under observation, and then researchers can use
confocal microscope technology to observe the behavior of tissue and cells in different
locations while the patient undergoes treatment. This methodology can also be used to
monitor changes in pH, track the process of drugs interacting with cells and tissues, and for
numerous other uses.
A new focus
Combining optical microscopy with 21 st century digital imaging methods brings together a
range of emerging technologies. Together, they are changing the face of medical, chemical
metallurgical and other scientific disciplines, in ways that will have far-reaching implications.