Nanomedicine refers to the use of nanotechnology in health care. Nanotechnology means working with materials at the nano level -- a scale too small to be seen with a regular lab microscope. A nanometer equals one-millionth of a millimeter. That’s thousands of times smaller than the diameter of a human hair.
Nature has many nano-sized particles. People can also create them from things like carbon or silver. Nanomaterials are human-generated substances on the nano scale.
In nanomedicine, scientists are creating materials and devices that work with your body at the atomic or molecular level. This allows for very specific, targeted results and has the potential to limit side effects.
How Does Nanomedicine Work?
Think of nanomedicine this way: Scientists manipulate and engineer atoms and molecules to serve as tiny, very precise tools inside your body. For instance, because it operates on such a small scale, nanomedicine can deliver drugs to your body in a very targeted way.
Types of Nanomedicine
Nanomedicine is in its early days. But scientists think it will eventually have many medical applications. The main ways nanomaterials are being applied in medicine are for:
Diagnosis (nanodiagnosis). Nanoparticles could enhance technologies like ultrasound and MRI to produce much clearer images.
Treatment (nanotherapy). Nanoparticles are tiny enough to send drugs exactly where they're needed. Vaccines can use nanoparticles to prompt your immune system to make antibodies against a virus. Scientists are also studying the possibility of individualized treatments tailored to your genes.
Regenerative medicine. Molecules called carbon nanotubes are already being used to repair damaged tissues. In the future, they might be able to regrow nerves.
An experimental type of nanomedicine called theranostics combines diagnosis and treatment.
What Are Some Examples of Nanomedicine?
Some specific ways that nanomedicine is being used or studied are for:
COVID-19 vaccines. Nanoparticles are a key element of two of the COVID vaccines, those from Pfizer and Moderna. Those vaccines use messenger RNA (mRNA) to help you develop immunity to the COVID virus. But mRNA breaks down quickly. It needs something to carry it through your body before it falls apart. So scientists put it inside nanoparticles, which deliver it to your immune cells. There, it can do its work.
Cancer treatment.Chemotherapy delivers cancer-fighting drugs to your entire body. That's why you may lose your hair and have side effects like nausea. Nanomedicine lets doctors target the medicine to your cancer cells and limit damage to healthy ones.
MRIs. Magnetic resonance imaging (MRI) uses radio waves and magnetic fields to create detailed pictures of your organs and tissue. Some patients get what’s called a contrast material through an IV. It makes details more clear on the images. But fluorescent nanoparticles deliver clearer pictures than traditional contrast agents. Because the imaging methods that use them are simple and less expensive, they may eventually make MRIs more affordable.
Medical devices. Scientists hope nanotechnology will allow them to make more sophisticated version of implanted devices like defibrillators, pacemakers, and stents. With tiny chips and sensors, these devices could send data and warnings, release medicines, or allow your doctor to monitor you remotely.
Biomarker detection. Biomarkers show what’s happening in a cell or your body at a given moment. They can be warning signs for disease. For example, high cholesterol is a biomarker for heart disease. Doctors look for biomarkers through tests on your tissue, blood, and urine. Individual cells and proteins in your body also carry biomarkers. Nanoparticles are more sensitive to biomarkers, which could give doctors more precise measurements. They may be able to diagnose illnesses earlier as a result.
What Conditions Could Nanomedicine Be Used For?
In addition to cancer, nanomedicine has potential for treating these conditions:
Neurological disease. Your brain has a protective layer of cells that keeps larger molecules out. This is called the blood-brain barrier (BBB), and it presents problems when drugs need to get to your brain. Nanoparticles, because of their size, can cross the BBB. This offers promise for treating brain tumors, stroke, Alzheimer’s, and meningitis.
Eye problems. Your eyes also have barriers to protect them from foreign substances. Those defenses make it difficult for drugs to reach their targets. Drops, injections, oral medicines, and IVs -- the most common ways of delivering eye medicines -- all run into this problem. Nanomedicine offers ways to get the drugs where they're needed, using nanoparticles, special coatings on contact lenses, and implants. Nanomedicine can help treat conjunctivitis (pinkeye), cataracts, cornea injuries, macular degeneration, and glaucoma.
Infections. Nanomedicine can help detect bacterial infections and can deliver antibiotics in a targeted way. Medical devices like catheters and heart valves can be coated in nanomaterials that repel bacteria, which helps prevent infection.
Menopause.Hormone replacement therapy can relieve some symptoms. Studies have shown that giving these hormones through the skin is effective and avoids some of the problems linked to medicines you take by mouth. When the hormones are delivered via nanoparticles, people have fewer side effects such as rashes and blisters.
Blood disorders. Conditions such as leukemia, lymphoma, anemia, and hemophilia have traditionally been treated with chemotherapy, bone-marrow transplants, stem cell therapy, and medicines. Researchers are focused on using nanomedicine to develop artificial components of blood, which could take over some of the functions that blood diseases disrupt.
Spinal cord injury. When you get this type of injury, the trauma sets off a chain reaction that creates further nerve damage. Like your brain, your spinal cord has a layer of protective cells. Doctors have traditionally used high doses of a steroid to ensure it gets across that barrier. But that drug can have serious side effects at high doses, and it breaks down quickly. Nanoparticles can cross the barrier, deliver drugs where they need to go, and stay in your body longer. Nanomaterials also could help your body repair nerve damage by limiting scarring and blocking substances that slow growth. Doctors eventually hope to use structures made of nanomaterials as "scaffolds" to guide the growth of new nerve tissue.