Nanotechnology has advanced to such a degree that there are now companies whose sole focus is to act as nanoparticle suppliers. They offer a variety of engineered nanoparticles that can be used in research and development, but more importantly, these companies may provide the foundation for the burgeoning nanotechnology industry.
Nanotech is expected to take over both science and technology in upcoming decades, so our future may soon be closely related to what suppliers of engineered nanoparticles choose to do with their businesses.As is often the case with major advances, the medical community stands to gain the most from this new technology.
Nanoparticles have been used for such a diverse range of medical applications that it is almost impossible to name them all; researchers have engineered blood nanoparticles to create a synthetic blood cell that can enhance human performance many hundreds of times over; they have likewise invented a “nanobone” that is stronger and more effective than natural human bone; and so on and so forth. But when it comes to cancer research, the results of using engineered nanoparticles are really startling.
Researchers at the University of Central Florida have found a way to engineer nanoparticles so that they become weapons in the fight against cancer. In their experiments they used a pharmaceutical drug known as Taxol, which is commonly used in chemotherapy.
The problems with chemotherapy are numerous; one of the reasons it tends to be so painful and unpleasant for the patient is because our current system for delivering the drug is limited to intravenous transfusion. Putting a strong chemical into the bloodstream is like using a jackhammer to hammer in a nail.
The circulatory system will indiscriminately distribute anything it carries to many, if not all, parts of the body. This means that a good deal of the healthy tissue in our bodies gets damaged or even destroyed along with the malignant tumors that the drug was meant to attack. Not only this, but the blunt effects of chemotherapy do not have the delicate control necessary to ensure that every molecule of the tumor is eliminated; if even one particle of malignant tissue survives the treatment the cancer has the possibility to re-grow, making the chemotherapy a failure. So how do we solve these problems?
For UCF assistant professor J. Perez, the answer was simple: use nanotechnology. The main difficulties associated with chemotherapy arise from our inability to interact with viruses, cancers and other pathogens at the molecular level; but nanoparticles are small enough that they can do so.
Perez and his group of researchers engineered specific nanoparticles so that they could identify and target only cancer cells. The particles were each equipped with a dose of Taxol so that when they encountered the malignant tumor tissue, they could then release the drug and kill off the cancerous cells one at a time. If this system of nanoparticle drug delivery were widely adopted for cancer treatment, much of the pain and discomfort resulting from chemotherapy treatment would thus disappear while at the same time increasing Taxol’s effectiveness.
Perez and his team accomplished this feat by attaching the delivery nanoparticles to a folic acid derivative; for cancer cells this vitamin is equivalent to an irresistible junk food. They draw the nanoparticles in, only to find that they are carrying poisonous Taxol. By then it’s too late.
The researchers also equipped each nanoparticle with a magnetic core composed mainly of iron oxide, as well as a strong fluorescent dye. Both of these traits make the particles easy to track and control once they are inside the human body.
The fluorescent nature of the nanoparticles allows doctors to follow them using optical imaging technology, while the iron oxide allows them to be tracked using an MRI machine. Doctors and patients would virtually be able to sit and watch the cancer being destroyed in one session. It also means that doctors will be able to see exactly what is happening and respond to new developments almost the minute they unfold.
Perez’s team also provided a failsafe mechanism for the cancer-killing nanoparticles; they can be engineered with or without the drug and used as contrast agents for the cancer. In this situation, if no cancer was found to exist in the patient’s body, the biodegradable nanoparticles would simply detect the absence of malignant tissue and instead of binding to any tissue surface they would continue passing from the bloodstream and get processed out of the body by the liver.
The iron oxide core serves a double purpose in this scenario. If no cancer exists, then there is no need for an MRI to track the nanoparticle, so as the liver eliminates it, the iron core is processed out and used to nourish the body. Since the majority of today’s population is always a bit low on iron, this actually does some good.
Other cancer solutions that use nanoparticles have been proposed and many more probably will be brought forward in years to come, but what sets the Perez team’s innovations apart is the dual nature of their specially-engineered nanoparticle.
They not only use the particle to perform both the diagnostic and therapeutic functions in one blow, but have also constructed and modified the nanoparticle in such a way that it is at the same time biocompatible and biodegradable. It sounds simpler than it is; combining four brilliant characteristics into one microscopic vessel is actually quite a feat.
Engineered nanoparticles like these have the potential to do almost anything. From treating dangerous diseases at an early stage to literally supplementing the immune system for people with autoimmune deficiencies such as AIDS sufferers, they can go anywhere and everywhere because of their extremely tiny size. They can also be used to modify almost any substance, from delicate electronics to the fabric your clothes are made out of.
Researchers have already developed “self-cleaning” fabrics whose nanoparticles actually “eat” stains; Eddie Bauer recently debuted its self-cleaning khakis. But no matter what engineered nanoparticles are used for, one thing is certain: they are out to change the world.