In the medical field, detection methods are king. There’s no better way to protect someone from disease or cancer than to know how to catch it early, in the least invasive way.
The Human Genome Project has already mapped out our genetic code, making it easier to study and pinpoint where harmful sequences may pop up. However, genes don’t directly interact with most of the processes in the body, they’re just the blueprints for the proteins that do.
Proteins are a bit trickier to analyze, since they can be insanely complex. There are twenty-one amino acids that make up the individaul building blocks of proteins. Those amino acids are strung together in chains called peptides, folded into three dimensions, and then possibly accessorized by other smaller proteins, fatty acids, or metallic ions. Most of the protein structure has no charge, expect for specific sites that are customized to interact with specific molecules.
Proteins can’t be replicated in mass like DNA and RNA can. Most labs use a molecule structure that the protein will latch onto, separating it from the original mixture. Then they take the sample of proteins and bombard it with x-rays. The image captured of the x-rays bouncing off the protein molecules reveals the structure. However, in order to perform this method successfully, you really need to know what you’re looking for beforehand.
Now, an easier and more straightforward way might be just over the horizon. A team at Arizona State University, led Stuart Lindsay, created a device that measures the unique electrical charge from each type of amino acid, one at a time. A charged “tail” attaches to the end of the protein and pulls it through the a hole opening just nanometers thick (called a “nanopore”) and two electrodes record the charges of the molecules that pass by. The researchers were able to distinguish between different amino acids, whole proteins that are mirror images of each other, and proteins with or without accessory molecules attached.
Lindsay and his team are now working on a a fast and cost-effective prototype for clinical use.
Check out the video of the nanopore device below:
Video Credit: Biodesign Institute at Arizona State University