As our ability increases to work with matter on the scale of nanometers, we are finding more and more applications for nanomaterials across a huge range of industries. The field of medicine will be amongst the most affected by the rise of nanotechnology, as it coincides with our increasing understanding of biology and medicine on the molecular scale.
Nanostructures, which are of a suitable size scale to interact directly with many biological structures and systems, are going to be a vital tool for physicians to gain better information about patient's bodies, and will allow them to work directly with the body to prevent and cure diseases.
Figure 1. Gold nanoparticles functionalized with DNA, RNA or protein strands can be used to deliver drugs to the place in the body where they are needed.
A major focus of nanomedicine research to date has been novel methods of targeted drug delivery using nanocapsules and functionalized nanoparticles. Nanoformulations of existing drugs can enable simpler administration, increased safety, or increased efficacy. There has also been a great deal of research interest in nano-enhanced diagnostic systems.
Nanoparticles and other nanostructured devices have been found to be more effective at detecting or quantifying disease markers than more conventional counterparts, particularly when looking for very small quantities of a chemical.
Antimicrobial surfaces and products using nanoparticles are also becoming more and more commonplace, in consumer products as well as in medical equipment such as catheters, dressings, and surgical tools. Silver nanoparticles, the most commonly used antimicrobial nanocoating, has been shown to be highly effective at destroying a range of bacteria and other microbes - much more effective than silver in its bulk form.
|Figure 2. Tumor cells can be targeted using functionalized nanoparticles. The principles of personalized medicine can help to design the nanodrug to be as effective as possible for each patient.
Personalized medicine is a huge movement in the modern medical world. It aims to move away from the traditional practice of prescribing standard doses of standard drugs for a condition to every patient, and shifts the focus onto targeting the precise drug and dose required according to the patient's physiology.
This is achieved by detecting and tracking molecular biomarkers, which indicate the presence and level of activity of a particular biological system in a patient's body, whether inherent or foreign.
Another major part of the emerging field of personalized medicine is pharmacogenomics - analyzing the genetic makeup of the patient to determine whether a particular medication will be successful, or if it will have any adverse effects.
This is particularly important in cancer treatment, where the chemotherapy drugs used can be very damaging to healthy cells as well as cancerous ones, and the exact genetics of the tumor cells can vary widely between patients, and even between locations in one patient's body.
Nanotechnology Solutions for Personalized Medicine
Most of the recent developments in personalized medicine have been directed at better diagnosis and treatment of cancer. Cancer is one of the biggest killers, and existing treatments can usually only improve the patient's chances - an outright cure is very rare.
Personalization of the treatment of cancer is a promising way to increase our ability to fight cancer, however, without necessarily requiring discovery of a revolutionary breakthrough drug. By determining which drugs a particular patient will respond best to, and the correct dosage, the possibility of adverse side effects can be greatly reduced.
There are several ways in which nanotechnology can help with these developments - primarily by making the diagnostic processes simpler, quicker, or less invasive by requiring less tissue.
Genetic analysis is a crucial part of personalized medicine, particularly in cancer treatments where the genetic signals can be so varied. Techniques are being developed for high-throughput DNA sequencing using nanopores, to obtain genetic information from a patient so that targeted medication can be selected as rapidly as possible.
The unique electronic and mechanical properties of nanostructured carbon materials like carbon nanotubes and graphene very interesting as the active components of nanosensors, which can detect incredibly small concentrations of a biomarker - in some cases down to as little as a few molecules.
Many of these technologies can be combined into a "lab-on-a-chip" - a portable diagnostic device which will be able to run tests rapidly and without requiring a large sample of tissue or blood. These devices will be able to be used in GP's offices, or in remote locations, which will make a huge difference to the speed at which a definite diagnosis can be given - a crucial step for cancer patients, where their chances can depend very strongly upon how early treatment starts.
Graphene nanopores can be used to sequence DNA. The DNA can pass through the pores, preventing the flow of ions through the pore, resulting in a characteristic electrical signal.
This research was published in Nature in 2010.
This sort of technology will also have a huge impact as the concept of personalized medicine spreads to include the treatment of a broader range of diseases. A commercial lab-on-a-chip, capable of diagnosing diseases rapidly, and providing the physician with enough information about the patient's physiology to select the correct drugs and dosages, would transform the world of medicine completely.
As well as providing a wider range of drugs by introducing the concept of nanoformulations, nanotechnology is capable of providing medical professionals with a vastly greater set of diagnostic tools, with less invasive procedures, and more rapid results. This will help to usher in the new age of personalized medicine, where all the additional data about the patient can be leveraged to tune the treatment to their precise needs.
This will have a particularly strong impact in cancer treatment, where the chemotherapy drugs which will have the least adverse effects on the patient can be selected. Drug delivery systems using functionalized nanoparticles can also be used in tandem with the diagnostic techniques to improve targeting of drugs to particular parts of the body.
As with all aspects of nanomedicine, there is a complex regulatory minefield to navigate before these technologies can see public use. Targeted drug delivery systems must be shown to be safe and reliable enough, and diagnostic systems must demonstrate a sufficient degree of accuracy. However, the benefits available from exploitation of this technology should drive the process forwards, and new research is emerging all the time which strengthens the case for nanotechnology in medicine.
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