What is Nanotechnology and How is it New?
For citizens in the developed world already exposed to the term ‘nanotechnology’, associated impressions may be that it deals with ‘very small things’, concerns ‘submarine robots in the bloodstream’ and brings with it the threat of ‘grey goo’c. The latter, more popular ideations, essentially stem from K. Eric Drexler’s proposal that atoms and molecules could act as self-assembling machinery, performing production tasks at the nanoscaled [15].
However, what is now universally accepted as ‘nanotechnology’, yet sometimes less noted, is an area evolving somewhat independently of Drexler’s visions. Following challenges from the general scientific community, on the basis of technological feasibility, Drexler renamed his understanding and aspirations for nanotechnology: ‘molecular manufacturing’. Thus, in the 21st Century, the term ‘nanotechnology’, whilst similar to molecular manufacturing in that it involves work on the level of atoms and molecules, refers to an applied science, focussed upon exploiting novelties arising from size-dependent phenomena exhibited in nanoscale matter. When dealing with matter below approximately 50 nanometres, the laws of quantum physics supersede those of traditional physics, resulting in “…changes to a substance’s conductivity, elasticity, reactivity, strength, colour, and tolerance to temperature and pressure” [16]. Such changes are useful to all industrial sectors where nanotechnology will enable smaller, faster, ‘smarter’, cheaper, lighter, safer, cleaner and more precise solutions [17-19]. For example, in the field of drug delivery, Peppas notes that nanoscale pH-sensitive hydrogels for treating patients with multiple sclerosis, “release at varying rates depending on the pH of the surrounding environment”, suggesting that “…these nanoparticle carriers may protect drugs from being broken down in the body until they reach the small intestine” [20]. Furthermore, progressing from the micro- to nano-scale involves inherent increases in a material’s surface area and surface-to-volume ratio that can be used to manufacturing advantage.
Ancient Origins of Nanotechnology
Yet, utilising science at the nanoscale is not new. For example, in the 4th Century A.D., the Romans applied gold and silver nanoparticles to colour glass cups [21]. The resulting artefacts were red in transmitted light and green in reflected light – a sophistication not reproduced again until medieval times. There are many scientists today who would argue they have been conducting research in the realms of the nanoscale since well before 1990.
Diagnosis and Treatment of Tuberculosis using Nanotechnology
Many believe nanotechnology offers new ways to address residual scientific concerns for Mycobacterium tuberculosis (TB). Declared a global emergency by the World Health Organisation (WHO) in 1993, the re-emerging threat of TB continues to be technically compounded by significant increases in the prevalence of multi-drug resistance (MDR), in a number of settings [38]. Treatments with improved sustained release profiles and bioavailability can increase compliance through reduced drug requirements and therein minimise MDR-TB ..
In India, the country with the highest estimated number of TB cases [41], research is underway into the role nanotechnology can play in addressing such concerns. A nanotechnology-based TB diagnostic kit, designed by the Central Scientific Instruments Organisation of India and currently in the clinical trials phase, does not require skilled technicians for use [42] and offers efficiency, portability, user-friendliness and availability for as little as 30 rupees [43] (less than US$1). In the Medical Sciences division of the U.S. Department of Energy, researchers are investigating an optical biosensor for rapid TB detection [44]. Furthermore, a group at RMIT University, in Australia, is conducting research into the application of novel tethered nanoparticles as low-cost, colour based assays for TB diagnosis...
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