Small Medicine

Big things are happening in the microscopic field of nanotechnology, which is defined as the study of objects less than 100 nanometers in size.  To put this into perspective, a piece of paper, or a human hair, are each about 100,000 nanometers thick.  That means that the study of nanotechnology deals only with sizes which are at least 1,000 times smaller than the diameter of a human hair.  Progress in nanotechnology is leading to major advances in many different areas, including crop protection, materials science, water purification and solar power.  In addition to these endeavors, some of the most remarkable work is being done in the fields of medicine and human health.  In order to give you a sense of the tremendous potential of nanotechnology, I will highlight just two of the most exciting ongoing projects. 
   There are a number of cancers which occur in the brain, however it can be very difficult to get drugs to the site of the tumor.  This is because the body has a natural defense called the Blood-Brain Barrier which blocks material from entering the fluid surrounding the brain.  In practice, this means that most cancers of the brain must be treated using surgery.  Researchers at Northwestern University are taking a radically different approach.  They have succeeded in attaching nucleic acids, the same material that comprises our DNA, to the surface of gold nanoparticles.  This nucleic acid-gold combination is called Spherical Nucleic Acids (SNAs), and miraculously this material is able to cross the Blood Brain Barrier.   Importantly, these SNAs can be designed in the laboratory to specifically target different type of cancer cells.  This technology is currently being used in a clinical trial to treat patients with a type of brain cancer called glioblastoma multiforme.  Although the research is still ongoing, the results thus far have been promising (see video below).

   The second project could ultimately give healthcare providers another way to tell what is happening inside a patient's body.  Bodily fluids such as saliva, sweat and tears contain very small particles called exosomes.  These particles, thousands of times thinner than a human hair, originate from the cells in our bodies.  Although small in size, exosomes contain a great deal of information regarding the overall state of our health. Researchers at IBM would like to analyze the information contained in exosomes, a type of liquid biopsy.  Using the techniques of nanotechnology, they are attempting to embed many of the processes available in a clinical lab on a single computer chip.  If successful, this would mean that a small sample of bodily fluid could be analyzed anywhere in the world using a simple handheld device (see video below).  Is it just me, or is anyone else thinking about Star Trek right now?   In closing, I hope you are convinced that big things are happening in the very small world of nanotechnology.