Remember the movie blockbuster Erin Brockovich? The film is based on a real world legal case that revolves around hexavalent chromium, also known as chromium (VI), used by the Pacific Gas and Electric Company to control corrosion in cooling towers in its Hinkley, CA compressor station. Chromium (VI), a natural metal, is known to be toxic and is recognized as a human carcinogen via inhalation. It also is widely used by industry in the manufacture of stainless steel, welding, painting and pigment application, electroplating, and other surface coating processes. Researchers in Germany now have developed a novel method of multilayer anticorrosion protection including the surface pre-treatment by sonication and deposition of polyelectrolytes and inhibitors. This method results in the formation of a smart polymer nanonetwork for environmentally friendly organic inhibitors.
Transparent conductive coatings pervade modern technology and they are a critical component of optoelectronic devices. Today, the most widely used standard coating in nearly all flat panel displays and microdisplays is indium tin oxide. As indium becomes increasingly scarce and expensive, the search for novel transparent electrode materials with good stability, high transparency and excellent conductivity has become a crucial goal for optoelectronic researchers. There are strong and successful efforts from several research groups around the world to develop optoelectronic devices on the basis of individual single-walled carbon nanotubes. This development is of great scientific interest, although there are major challenges in finding technologically feasible ways to assemble the individual nanotube devices into functioning electronic circuits with a high level of integration.
Modern pharmaceutics is a very imprecise, wasteful and sometimes even dangerous discipline. Not only do most drugs fail even before they make it to market (about 80% of drugs never make it through clinical trials) but even the efficacy of many drugs that are being prescribed for certain diseases is questionable. The most important challenge, though, is to deliver the correct dose of a particular therapeutic (small molecules, proteins, or nuclei acids) to a specific disease site. Since this is generally unachievable, therapeutics have to be administered in excessively high doses, thereby increasing the odds of toxic side effects. Nanotechnology offers great visions of improved, personalized treatment of disease. The hope is that personalized medicine will make it possible to develop and administer for each individual patient the appropriate drug, at the appropriate dose, at the appropriate time. The benefits of this approach are accuracy, efficacy, safety and speed. Today, commercial nanomedicine is at a nascent stage of development and the full potential of nanomedicine is years or decades away. Currently the most advanced area of nanomedicine is the development and use of nanoparticles for drug delivery.
The use of design concepts adapted from nature is a promising new route to the development of advanced materials. There are quite a number of terms such as biomimetics, biognosis, biomimicry, or even 'bionical creativity engineering' that refer to more or less the same thing: the application of methods and systems found in nature to the study and design of engineering systems and modern technology. And increasingly, nanotechnology researchers find naturally occurring nanostructures a useful inspiration for overcoming their design and fabrication challenges. Because biological structures are the result of millennia of evolution, their designs possess many unique merits that would be difficult to achieve by a completely artificial simulation. By replicating the eye of a fruit fly, researchers have now demonstrated a highly reliable and low-cost technique for making inorganic replicas of biotemplates for fabricating complex nanostructures with biologically inspired functionality.
Much is being written about nanotechnology's role in vastly improving the detection and treatment of cancer. Detection of cancer at the earliest stage provides the greatest chance of survival. Unfortunately, cancer has a logarithmic growth rate. A one cubic centimeter size tumor may have 40-50 cell divisions and typically doctors don't see 80% of the life of a tumor. The detection of a protein pattern in blood serum can be helpful in evidencing a possible presence of cancer at an early stage. The problem is that 'early' means the capability of detecting very few molecules in dilute conditions. Now, in another step to improve the design and fabrication of devices for single molecule detection, new research has demonstrated an experimental capability of detecting down to as few as 10 organic molecules deposited on a quantum dot.
One term you hear quite often in discussion about the potential risks of nanotechnology is 'precautionary principle'. This moral and political principle, as commonly defined, states that if an action or policy might cause severe or irreversible harm to the public or to the environment, in the absence of a scientific consensus that harm would not ensue, the burden of proof falls on those who would advocate taking the action. The principle aims to provide guidance for protecting public health and the environment in the face of uncertain risks, stating that the absence of full scientific certainty shall not be used as a reason to postpone measures where there is a risk of serious or irreversible harm to public health or the environment. In 2001, an expert panel commissioned by the European Environment Agency (EEA) published a report, Late Lessons from Early Warnings: The Precautionary Principle 1896-2000, which explored 14 case studies, all of which demonstrated how not heeding early warnings had led to a failure to protect human health and the environment. It looked at controversial topics such as asbestos, Mad Cow Disease, growth hormones, PCBs and radiation - all of which demonstrated how not heeding early warnings had led to a failure to protect human health and the environment. The expert group that compiled the EEA report identified 12 'late lessons' on how to avoid past mistakes as new technologies are developed. These lessons bear an uncanny resemblance to many of the concerns now being raised about various forms of nanotechnology.
Modern medicine would be unthinkable without biomedical implants. The market for medical implant devices in the U.S. alone is estimated to be $23 billion per year and it is expected to grow by about 10% annually for the next few years. Implantable cardioverter defibrillators, cardiac resynchronization therapy devices, pacemakers, tissue and spinal orthopedic implants, hip replacements, phakic intraocular lenses and cosmetic implants will be among the top sellers. Current medical implants, such as orthopedic implants and heart valves, are made of titanium and stainless steel alloys, primarily because they are biocompatible. Unfortunately, a common complication associated with medical implants results from infectious biofilms which may cause chronic infection that is difficult to control. For instance, biofilms are present on the teeth as dental plaque, where they may become responsible for tooth decay and gum disease. Because teeth are easily accessible, removing plaque is not a problem. If biofilms develop on medical implants deep inside the body, though, they can become a serious, sometimes life-threatening problem. Preventing or limiting the formation of bacterial biofilm on the surface of implanted medical devices is an important approach to control bacterial biofilm-related infections. A new study demonstrates the effectiveness of a process combining surface nanocrystallization and thermal oxidation for reducing the biofilm's adherence to stainless steel.
Any drug intended for systemic administration and all medical devices which will contact blood must undergo thorough biocompatibility testing. These tests include an in vitro assay to determine the material's potential to damage red blood cells (hemolysis). Hemolysis, the abnormal breakdown of red blood cells either in the blood vessels (intravascular hemolysis) or elsewhere in the body (extravascular), can lead to anemia or other pathological conditions. In the pharmaceutical industry, hematocompatibility testing is harmonized through the use of internationally recognized standard protocols. Nanotechnology- based medical devices and drug carriers are emerging as alternatives to conventional small-molecule drugs, and in vitro evaluation of their biocompatibility with blood components is a necessary part of early preclinical development. Many research papers have reported nanoparticle hemolytic properties but, so far, no in vitro hemolysis protocol has been available that is specific to nanoparticles. A new study published this month describes in vitro assays to study nanoparticle hemolytic properties, identifies nanoparticle interferences with these in vitro tests and provides the first comprehensive insight to potential sources of this interference, demonstrates the usefulness of including nanoparticle-only controls, and illustrates the importance of physicochemical characterization of nanoparticle formulations and visually monitoring test samples to avoid false-positive or false-negative results.