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As technology continues to advance the ubiquitous nature of certain devices prompts innovative people to come up with amazing new uses for everyday items. A perfect example of this is the cell phone. We’ve already shown you smartphones that can take and record ultrasound images as well as a nifty Android application that makes stargazing easy for the amateur astronomer in all of us. Now a team led by Dr. Daniel Fletcher at UC Berkeley in collaboration with researchers at UCSF have turned the smartphone into an incredibly effective microscopy device.

Light microscopy is a vital tool for the diagnosis and screening of various diseases. Unfortunately in many regions of the world access is limited due to availability or lack of portability. Dr. Fletcher’s group looked to solve this problem by taking off the shelf components and building a solution that would be cheap and effective. Fletcher’s group built a mobile-phone mounted light microscope, dubbed the CellScope, capable of providing images detailed enough to help diagnose diseases like malaria and tuberculosis. Using a mobile phone as the platform for the microscope also allows images to be saved and transmitted to clinical experts for further analysis.

The CellScope was put through it’s paces by Dr. Fletcher’s team as they tested it in various applications. As seen in the figure below sickle shaped red blood cells are clearly visible within the image of a blood smear sample allowing the diagnosis of malaria.

In addition to taking diagnostically clear images of blood smears, Dr. Fletcher’s group tested the CellScope with fluorescent filters to see if the CellScope could be utilized in an increasingly popular tuberculosis screening and monitoring assay.

As seen above the fluorescent staining of tuberculosis bacilli in spittum is remarkably clear for a microscope attachment on a mobile phone. In the C panel of the above figure, Dr. Fletcher’s group also attempted to harness the computational power of the mobile phone by developing software to automatically count and process the fluorescent image.

The CellScope’s effectiveness, portability, and low cost make it an incredible tool for health care providers throughout the world. More details available at PLoS ONE.

(PLoS ONE: Mobile Phone Based Clinical Microscopy for Global Health Applications)

One thing great about basic biology research is that so much cool and inventive technology is built around trying to peer into the depths of how organs, tissues, and cells work their mojo. A lot of times, the best stuff is built around microscopy and imaging, because seeing is pretty much believing. And beautiful pictures make scientists just as happy as it does everyone else.

There’s an imaging technique that’s been emerging over the last ten or so years called imaging mass spectrometry, which can tell you where a whole bunch of different molecules are in tissue all in one go! Basically, you take a slice of the tissue you want to image, apply a chemical resin to it (which is called a “matrix”), and then you shine a fairly strong laser at the tissue. This causes a physical reaction in which the resin absorbs the laser, ionizes, and causes molecules from the tissue to get ejected into the air. The mass spectrometer then sucks those ejected molecules into its cavernous depths and weighs them, breaks them apart, and then weighs their fragments to try to identify what the molecules are. For proteins, this identification process is actually quite easily done.

What you end up with is a really remarkable picture, a 2D map of where a range of different molecules are in the slice of tissue. You can look at the distribution of molecules of different specific weights across the entire slice. By stacking images of adjacent slices, you can then reconstruct an approximate 3D map of where molecules are in a tissue, like a brain or a tumor. Pretty neat!

A section of a mouse brain imaged for molecules of various weight (from Stoeckli et al. (2001) Nature Medicine 7, 493–496.)

Up until now, there have been two main ways to see macromolecules like proteins and RNA in biological tissue. First, you can look at where a specific macromolecule is by sticking a fluorescent dye to it and looking for that “tag.” It’s a great technique, but it’s also pretty laborious and limited in scope, because you can only examine at most three or four things at a time or the colors will start overlapping together a little too much to reliably distinguish what you’re looking at. In addition, you have to know what molecules you’re interested in first in order to tag them.

Second, you can look at cells as a whole using high energy techniques like transmission electron microscopy (TEM), which uses beams of electrons to “X-ray” cells. Since electrons have a very short wavelength, that means that they can be blocked and scattered even by very small structures, including groups of proteins, which means that a TEM image can look at a lot of things with an insanely high amount of detail. Unfortunately, electron microscopy won’t really tell you what you’re looking at, though there are a few techniques (like sticking gold beads to stuff you’re interested in) that try to get around that. Nonetheless, it doesn’t tell you much besides the overall “visual” picture.

Imaging mass spectrometry gets over a lot of these hurdles of traditional microscopy by directly associating molecular weights with specific coordinates in a tissue sample. And because the mass spectrum measures a wide range of weights, a computer algorithm can potentially tease out patterns that might not have occurred to a researcher or doctor looking for a few things at a time. The amount of information that can be obtained from a simple mass spectrum image is tremendous. With newer, cheaper super-accuracy mass spectrometers coming out, such as the orbitrap, this technology is growing in popularity outside of specialized physics labs, and it promises to revolutionize the way a lot of science and medicine is done. In the clinic, for example, a ton more information could come out of a biopsy all at once using this technology, from identifying cancer markers to positively identifying infectious agents and inflammation. I look forward to what’s coming in the future!