Nanotechnology concepts were applied by scientists long before the field earned its name. However, historians tend to agree that the discipline’s beginnings are rooted in the mid-20th century, with a talk given to the American Physical Society by renowned physicist Richard Feynman.
In his talk, Feynman led the audience through the idea of a process to enable scientists to interact with, manipulate and control individual molecules and atoms. The term “nanotechnology” was brought into the English lexicon in 1974. However, the field was officially established in 1981 with the invention of the scanning tunneling microscope. This tool allowed researchers to view atoms individually for the first time, through the generation of spatial images.
Scientists utilizing nanotechnology have gone on to develop a number of new processes to provide solutions to complex problems in a wide range of industries, including agriculture, water purification and energy. However, nanotechnology arguably holds more promise for healthcare than for any other industry.
Though a relatively young field of science, nanotechnology plays a prominent role in Convergence in Healthcare, one of the most important modern approaches to medical research. As described in the 2016 report “Convergence: The Future of Health,” the concept is defined as an approach to the field of medical research that fully integrates the knowledge of experts from the physical science, life science, mathematics, computing and engineering sectors.
By embracing convergence, members of the scientific community are developing groundbreaking new methods for treating, diagnosing and preventing diseases that affect the global population. Among the most innovative discoveries made as a result of convergence are the advances related to the ability to engineer nanoparticles for the delivery of drug therapy to specific areas within the body, including the following recent advances listed below.
In 1998, geneticists Andrew Fire and Craig Mello discovered that short sections of RNA could interfere with the function of — or turn off altogether — certain genes within a cell. Since then, convergent research has led teams of scientists to employ the use of RNA interference to silence certain types of diseased cells that occur in the lining of organs and the growth of blood vessels, halting the development of illnesses such as diabetic retinopathy and atherosclerosis. Medical researchers silence these genes by enveloping interfering RNA (RNAi) within polymer nanoparticles capable of transporting the RNA therapy to target cells without them first being swept out of the bloodstream by the body’s immune system or liver.
Combination Therapies for Cancer Treatment
The same RNAi that allows for gene silencing in diseased cells of organ linings and blood vessels has also shown value as a tool to innovate the way chemotherapy is delivered within the body. According to the Centers for Disease Control and Prevention (CDC), around 650,000 cancer patients elect to undergo chemotherapy treatments every year. While the treatment undeniably saves lives, the powerful chemicals used to target and kill cancer cells in the body often end up destroying healthy tissue alongside tumors. This, in turn, makes many chemotherapy recipients extremely ill.
Using nanotechnology, the same RNA packages described above could hone in on the proteins produced only by genes within cancer cells, more tightly controlling where drug therapies are administered within the patient’s body. Additionally, scientists are developing “smart” nanoparticles to deliver multiple drug therapies to cancer cells in sequence.
For example, of the two drugs delivered to a target site, the first curtails the cancer’s growth down a tumor pathway. The second drug, delivered by the same nanoparticle hours later, introduces a drug to break down the tumor’s DNA. Together, this form of chemotherapy offers cancer patients a much stronger treatment and more effective against aggressive tumors than the methods currently available.
Drug Delivery to the Brain
The medical community has learned significantly more about the brain with the invention of imaging tools such as magnetic resonance imaging (MRI). However, the brain remains the most complex and mysterious organ in the human body. Treating diseases that manifest in the brain is complicated not only because of the brain’s intricacy, but also because of protective elements such as the blood-brain barrier, which prevents larger molecules from entering the brain. This includes molecules such as toxins and pathogens; unfortunately, it also keeps out proteins and peptides and potential therapeutic agents that could help treat disease.
Convergence-based research has begun to explore ways scientists may circumvent the blood-brain barrier to treat diseases in the brain. Scientists are exploring the potential of nanoparticles covered by polymer exteriors. These nanoparticles contain a protein or a portion of an RNA molecule capable of delivering targeted drug therapies.
Some of these polymer-covered nanoparticles dissolve to release encased drug therapies, others release a drug therapy when they encounter a specific target, some are carried by immune cells into target sites within the brain to release a drug therapy upon arrival, and still others remain wholly in the brain and allow the therapy they contain to function from within them. The ultimate goal of medical researchers leveraging nanotechnology to treat brain-related illnesses is the development of nanoparticles to allow them to control the exact timing, physical action and dosage within the brain.