The Pharmaceutical Applications Of Nanotechnology
Like the lethal nano-swarm envisioned by author Michael Crichton in his novel “Prey” nanotechnology has escaped the realm of science fiction in recent years and begun making incursions in the real world. Rather than doing harm, though, nanotechnology is being harnessed for the benefit of mankind. Nanomaterials are generating buzz and driving innovation in any number of industries, including cosmetics, textiles, pharmacology, medicine, food, energy and so on.
Of course, pharmacology, especially, stands to benefit from obvious opportunities presented by the unique physical and electrochemical properties of nanomaterials. Because of their extraordinarily small dimensions, nanoscale substances are capable of venturing effortlessly where other molecules can’t go. They can be designed from biocompatible (and biodegradable) constituents, and used to enhance the stability of otherwise fragile therapeutic molecules, for instance.
In short, it's hoped they can improve drug solubility and bioavailability, enhance therapeutic molecule stability, and/or improve delivery of therapeutics to specific sites of action. Clearly, these properties will ensure the importance of nanomaterials to the design and delivery of drugs for the foreseeable future.
However, it’s still in the early days, and the full potential of these remarkable materials continues to be investigated and illuminated. Given that novel, versatile properties seem to emerge on a regular basis — the therapeutic applications of nanomaterials are continuing to grow. Presently, more than 200 products facilitated by or directly related to the use of nanotechnology have undergone clinical trials and are being used to improve patients’ lives. Nanotechnology is already being used to improve the bioavailability of certain therapeutic drugs, for example.
Advances and Opportunities
A significant remaining hurdle has been to devise a way to deliver proteins and polypeptides using nanomaterials. The technological challenges of joining appropriate nanomolecules to proteins are considerable, but they’re not insurmountable.
Just recently, researchers at the University of Buffalo announced they’d designed a method for joining polypeptides to the bilayers of preformed cargo-loaded liposomes. This enabled tumor targeting, without disrupting bilayer integrity. While it’s been possible to bind nanoparticles to protein fragments for a while, these early attempts yielded unstable peptides, and were unsuitable for use in the human body.
However, researchers at UB appear to have solved the problem. In a press release, team leader, Jonathan F. Lovell, PhD, said, “We have proven that you can easily attach proteins to nanoparticles and, like Velcro that doesn’t unstick, it stays together.” The opportunities for oncology drug delivery are intriguing, to say the least. Already, Lovell’s team has demonstrated, in vitro, that tumor-targeting proteins can be delivered in this manner to cancer cells. The nanomedicine homed in on diseased cells like heat-seeking missiles acquiring a target and delivering a deadly payload.
Another example of the use of nanotechnology involves gelatin-based nanoparticles. Recently, they were used to deliver a protein that combats the deleterious effects of stroke. Gelatin nanospheres containing neuroprotective Osteopontin were successfully delivered to the brains of test rodents, intranasally. The gelatin nanospheres encapsulating the therapeutic protein facilitated penetration of the blood-brain barrier in a timely fashion, without the need for surgical delivery.
The development of nanoparticle-based caspase sensors provides yet another example of the seemingly endless possibilities for innovation enabled by nanotechnology. Caspaces are enzymes released by cells during inflammation, apoptosis and necrosis. Measuring these proteins in vitro, or better, in vivo — in real time, with specificity, precision and sensitivity — has been an eagerly anticipated goal in medicine. Already, several nanoparticle-based assays are reaching the market.
Ongoing research hints at the potential usefulness of nanoparticles in boosting immunity, too. As noted in a recent article in Nanomedicine, properties including “…adjuvanticity, capability to enhance cross-presentation, polyvalent presentation, siRNA delivery for silencing of immunesuppressive gene, [and] targeting and imaging of immune cells…” should prove invaluable in advancing the fields of vaccination and immunotherapy.
New and Emerging Frontiers
“Nanoregeneration" represents yet another branch of nanomedicine with an exciting future. This subspecialty of nanobiomedicine seeks to harness the unique properties of nanomaterials to meet the formidable challenges of advancing regenerative medicine. Already, nanomaterials are being used to create “nanoscale topographies” to enhance osteogenesis when it’s necessary to regrow or resculpt bone. An important theme of nanoregenerative medicine appears to be the regulation of cellular function through nanotopographical modification.
Using stem cells, “nanoreservoirs” of growth factors, and other cellular components, there’s hope that our ability to regrow tissues, and even organs, will advance much more rapidly than has previously seemed possible. Nanotechnology has even been used to enhance osteointegration of titanium alloy implants with living bone tissue. Using lasers, investigators have learned how to create nanotoptgraphical modifications that facilitate the osteointegration of synthetic joints and other implants. This speeds healing and underscores the promise of nanotechnology in general: The possibilities appear nearly limitless at present to rapidly advance the noble goals of medicine.
Brady Veitch directs market research and analysis for Microfluids. He has over 10 years’ experience as a cross functional leader in product management, market intelligence and strategic planning, with a specialized focus in Healthcare, Biotech, Pharma and Medical Device sectors.
photo courtesy of theconversation.com
Tag(s) : nanomedicine, proteins, nanospheres, caspase sensors, nanoregeneration, microfluids,