A very basic definition of ‘nanotechnology’ interprets it as ‘the engineering of functional systems at the molecular level’. A more generalized description was established by ‘National Nanotechnology Initiative (US)’ which defines nanotechnology as the manipulation of matter with at least one dimension sized from 1 to 100 nanometers. One nanometer (nm) is one billionth part of a meter, or 10-9 of a meter. The comparative size of a nanometer to a meter is the same as that of a marble to the size of the earth. Scientists discovered that materials in nano dimensions exhibit properties that are significantly different from the same materials at macro scale, such as increased strength, resiliency, electrical conductivity, lighter weight, higher chemical or physical reactivity, etc. Thus, if we can understand these differences and learn their smart and wise utilization, then there are endless possibilities for improved devices and materials. Presently, scientists and engineers are exploring a variety of ways to make materials having nano dimensions to take advantage of their altered properties. Nanotechnology is often considered as a new revolution, as was the industrial revolution, as its revenues are estimated to reach $1 trillion worldwide by 2015.
The concept of nanotechnology started with a talk entitled ‘There’s Plenty of Room at the Bottom’ which was delivered by physicist and future Nobel prize winner Richard Feynman at an American Physical Society meeting at the California Institute of Technology (CalTech) on December 29, 1959. In the talk, Feynman focused on the field of miniaturization and described a process in which scientists would be able to manipulate and control individual atoms and molecules. Professor Norio Taniguchi coined the term nanotechnology over a decade later during his ultra precision machining. Though nanotechnology deals at atomic level, it was impossible to see an atom with the microscopes then available. Modern nanotechnology came into existence once the scientists had the right tools, such as the scanning tunnelling microscope and the atomic force microscope, which are being clubbed with precise analytical techniques to develop more sophisticated solutions, like atomic force microscopy clubbed with Raman spectroscopy.
There are two main approaches which can be used to create nanoconstructs: ‘Bottom-up’ and ‘Top down’. In the ‘bottom-up’ approach, materials and devices are built from molecular components which get assembled chemically by following the principles of molecular recognition. In the “top-down” approach, nano materials are obtained from larger entities without any atomic-level control.
Nanotechnology, though means nanosized, is a very large term in itself. It is a fast emerging technology which has its impact on almost every disciple of science, such as surface science, material science, semiconductor physics, microfabrication, molecular biology, organic chemistry, and many more. And because of this variety of potential applications, governments across the globe have invested billions of dollars in this field of research. Through its National Nanotechnology Initiative, USA has invested 3.7 billion dollars. The European Union and Japan have invested 1.2 billion and 750 million dollars respectively. Report of the ‘Project on Emerging Nanotechnologies’ (august 21, 2008) estimated that over 800 manufacturer-identified nanotech products are publicly available, with new ones entering the market at a rate of 3-4 per week. The project listed all of the products in a publicly accessible online database. While several of nanomaterials are still under the process of research and development in various laboratories worldwide, some are already in use in different areas of life and society.
Nanotechnology has numerous applications and provides plenty of advantages in all the applied fields. One of the most important applications of nanotechnology is in the pharmaceutical industry. Nanotechnology has emerged as a boon for medical world, as it helps in developing smart drugs and dosage forms. These result in a faster cure and lesser side effects. As life saving tools, nanotechnology is unsurpassed in its promise of an absolute revolution for treatment of previously incurable or untreatable conditions. According to the National Institute of Health (NIH) Nanomedicine Roadmap Initiative, ‘nanomedicine’ refers to highly specific medical intervention at the molecular scale for diagnosis, prevention and treatment of diseases. The nanotechnology has a multifaceted approach in the field of pharmacy. It starts from a stage as early as the development of new drugs with a specific role, and goes till the fabrication of novel drug delivery systems providing a targeted, controlled release of the drug, also overcoming its inherent limitations. The ultimate goal of the nanotechnology is to improve the current therapeutic and diagnostic modalities in a way that the patient enjoys maximum benefits with least unwanted side effects.
Pharmaceutical industry enjoys numerous applications of nanotechnology, most promising applications being: targeted delivery; controlled (sustained or prolonged) delivery; improving bioavailability; increasing solubility of poorly soluble drugs; improved patient compliance; reducing unwanted side effects; better diagnostic devices, and many more. Nanoformulations act as a significant tool for overcoming the limitations of conventional formulations. Anti cancer nanoparticles specifically target cancer cells only, sparing the normal body cells, unlike conventional anti cancer formulations which kill cancer and normal cells both. Nano sized dosage forms can be used to target brain, as these can cross blood brain barrier due to their extremely small size. Nanomedicines for the dreadful diseases like cancer, tuberculosis, AIDS, diabetes, malaria, hepatitis, glaucoma, etc have been developed and are in different trial phase for the testing. Few of them have been commercialized; others are on their way to the health market. AbraxaneÂ®, a chemotherapeutic agent (albumin bound nanoparticles of paclitaxel) created by Abraxis is one of the examples of commercialized products. DaunoxomeÂ®, DoxilÂ®/CaelyxÂ®, MoetÂ® and AmbisomeÂ® are few more examples of commercial products. Nanotechnology has also brought a revolution in the field of manufacturing materials, known as nanomaterials. Many of these nanomaterials find their applications in regenerative medical science, such as creating artificial skin, bones and cartilage for human use.
The nanotechnology in drug delivery technologies can be classified into three categories: before nanotechnology revolution (past); current transition period (present); and mature nanotechnology (future). The nanosized drug delivery systems of the past include liposomes, polymeric micelles, nanoparticles, dendrimers, and nanocrystals. The current drug delivery systems include microneedle-based transdermal therapeutic systems, microchips, layer-by-layer assembled systems, and various microparticles. The fabrication methods for these are in the development stage. The future of nanotechnology in healthcare is concerned with the development of nano manufacturing processes that can churn out nano drug delivery systems.
If we talk about the applications of nanotechnology in pharmaceutical industry, it is not only limited to precise and effective administration of drugs, but also includes improved cosmetics and other over-the-counter products. Nanotechnology has been applied in cosmetic and beauty products through enhancing antioxidant and anti-microbial properties. Many sunscreens contain nanoparticles of zinc oxide or titanium oxide.
Nanotechnology has incredible potential for revolutionizing the therapeutics and diagnostics dimensions of healthcare industry. But to realize and utilise this potential, continued support by funding agencies and an efficient workforce are require.
Along with these and several more advantages and applications of nanotechnology, this field also suffers from few challenges. The biggest challenge in nanotechnology is that we need to learn more about materials and their altered nanoscale properties. All over the world, universities are rigorously studying and carrying out research on nanotechnology. Presently, nanotechnology is an expensive process. This is actually the result of high cost procedures and lack of sufficient number of efficient nanotechnology experts. Along with a growing debate on the safety risks of nanotechnology, there has been call for tighter regulation of nanotechnology. And also, there is significant debate about common body responsible for its regulation. Some regulatory agencies currently cover some nanotechnology products and processes to varying degrees. Regulatory bodies such as the United States Environmental Protection Agency and the Health & Consumer Protection Directorate of the European Commission have started dealing with the potential risks of nanoparticles.
As we stand now, nanotechnology is the new frontier and its potential impact is compelling. But there is still a long way to go. Scientists believe that within the next twenty years we will achieve a lot in the field of nanotechnology. By that time, the industry will need a huge number of well trained and efficient scientists, engineers, and technicians in this area. As estimated, the exciting industry of nanotechnology will need 2 million workers worldwide by 2015. The workforce will be required from all areas of science and engineering and will include those with technical and diploma degrees up to PhD degree holders. A skilled workforce trained at a variety of levels is needed to meet the projected workforce challenge of 2 million workers. Career areas and opportunities are as diverse as producing better drug delivery systems and cosmetics to designing medical agents and diagnostic devices, or researching and exploring the hidden potential. The success will all depend upon knowledge and skills of the professionals.
Overall, nanotechnology is aimed at advancing the tools and procedures required to provide human beings with a better life