American physicist Richard Feynman is generally acknowledged as having inspired the development of nanotechnologies through his There’s plenty of room at the bottom lecture at the 1959 American Physical Society (APS) Meeting1. Feynman suggested that the entire 24 volumes of Encyclopaedia Britannica could be made to fit on a pin head and offered a $1,000 reward to the first person who managed to reduce a page of text to the required linear scale of 1/25,000. Stanford University graduate student Thomas Newman claimed the reward in 1985, having used electron beam lithography to etch the opening page of Charles Dickens’s A Tale of Two Cities onto a 200 x 200 μm square of plastic.
However, it was not until after the publication of Eric Drexler’s book Nanosystems: molecular machinery, manufacturing and computation2 in 1992 that the practical molecular field—or nanotechnology and nanomanufacturing—started to gain recognition. Drexler envisaged nanomachines and the possibility of building molecular electronic circuits, and this is still the subject of current research. Later, it was an understanding of the unique physical properties of matter at the nanoscale (1–100 nm) that established the field of nanotechnology. These properties, which vary in thickness and size, are due to the large surface area-to-volume ratio, making them virtually 2D structures and chemically more reactive than 3D structures associated with bulk materials.
Nanotechnology is now an enabler for the production of autonomous nanoparticles and high-strength coatings and ultra-thin films used in many sectors of industry. Applications include battery materials, insulators, new drugs, optical displays, paints, printing inks and sensors.
There is a plethora of publications, reviews, conferences, websites and market surveys etc on applications, materials and products realised as a result of nanotechnologies. Recently published estimates show there are now more than 290,000 nanomaterials, 790,000 nanotechnology articles and 23 million nanotechnology patents3.
In 2018, the global nanotechnology market was valued at over US$1,055.1 million4. This is projected to reach $2,231.4 million by 2025, growing at a compound annual growth rate (CAGR) of about 10 percent from 2019 to 2025.
Nanomedicine
The fastest growing and most popular application of nanotechnologies is nanomedicine. It involves the use of nanoscale materials such as biocompatible nanoparticles for sensing, diagnosis and targeted drug delivery. Size matters because most basic biological mechanisms in the human body take place at the nanoscale. In fact, the human body is the most efficient nanomanufacturer. It is estimated that about two million cells are produced in the body every second to replace dying cells.
Due to their size (10–100 nm), nanoparticles can flow through capillaries in the circulatory system and penetrate cells. This enables them to be used as molecular carriers to deliver anti-cancer drugs directly to specific cancer cells. Targeted drug delivery is now a major objective in medicine. It is a cost-effective therapy that minimises the deleterious side-effects experienced with chemotherapy and other more traditional treatments. Intensive research is producing positive results for the use of gold and other nanoparticles in the diagnosis and treatment of cancer tumours. Nanoparticles can be made from a variety of materials that include polymers, metals or ceramics. Their size, charge, surface chemistry and shape can be adjusted as required for specific treatments.
Smart multifunctional nanoparticles that change their structural or functional properties in response to specific external stimuli such as electric or magnetic fields, radiofrequencies (RFs), ultrasound and X-rays are being developed. These nanoparticles are capable of facilitating tuneable drug release tailored to patients’ individual needs.
There has been a surge of interest in nanoparticles and nanotechnology-based processes amongst clinicians and medical device and pharmaceutical manufacturers5. Advanced research into the use of nanoparticles for cancer diagnosis and treatment is supported and endorsed by the US’s National Cancer Institute (NCI)6. Indeed, they have provided an extra stimulus for the development of new cancer drugs. The global market for nanoparticles in biotechnology and pharmaceuticals is estimated to be $79.8 billion7.
Progress in cancer nanotechnology requires a better understanding of how molecular-targeted nanoparticles interact with live cells. Here, when cancer cells (cell nuclei in blue) were treated with antibody-conjugated nanoparticles, the antibodies (red) and the nanoparticle cores (green) separated into different cellular compartments. Such knowledge may lead to improved methods of cancer detection in vivo as well as better nanoparticle-based treatments. Source: the National Cancer Institute/M.D. Anderson Cancer Center; Creators: Sangheon Han, Konstantin Sokolov, Tomasz Zal and Anna Zal.
The future
It is gratifying that since the publication of my Commercialising nanotechnology, concepts-products-market paper on the market potential of nanotechnologies in 20068, there has been an explosion of new applications, products and markets. Healthcare, medical device and pharmaceutical are among the fastest-growing industries. Many factors contribute to this, but their development of innovative products, processes and services has resulted from the exploitation of micro and nanotechnologies (MNTs).
There are thousands of biomedical research projects in progress around the world. Many have passed the proof-of-concept stage, but progressing beyond this demands the integration of many different technologies as well as strict adherence to health and safety rules and regulations. Drugs have to go through a series of patient clinical trials before becoming accepted for general use. In addition, financial investment is only forthcoming if they are deemed to be commercially viable.
The first steps have been taken on the long road of discovery that could lead to the elimination of known diseases, but many challenges have to be faced before such a goal can be reached.
References
1Kornei, K. (2016). The beginning of nanotechnology at the 1959 APS Meeting. APS News, November 2016, volume 25, issue 10, pp. 4 and 7. Available at: http://bit.ly/2CdiSVG
2Drexler, K.E. (1992). Nanosystems: molecular machinery, manufacturing, and computation. New York: Wiley.
3Content at a glance [homepage]. Nano. Available at: go.nature.com/2qfYu3q
4Tewari D. and Baul, S. (2019). Nanotechnology market by type (nanodevices and nanosensors) and application (electronics, energy, chemical manufacturing, aerospace & defense, healthcare, and others): global opportunity analysis and industry forecast, 2018–2025 [report]. Allied Market Research. Available at: bit.ly/32786ei
5Chandra, G. and Srivastava, D. (2019). Nanomedicine market by modality (treatments and diagnostics), application (drug delivery, diagnostic imaging, vaccines, regenerative medicine, implants, and others), and indication (oncological diseases, infectious diseases, cardiovascular diseases, orthopedic disorders, neurological diseases, urological diseases, ophthalmological diseases, immunological diseases, and others): global opportunity analysis and industry forecast, 2017–2023 [report]. Allied Market Research. Available at: http://bit.ly/2PDAOkw
6Cancer and Nanotechnology [web page]. National Cancer Institute. Available at: http://bit.ly/2qhKNkz
7Highsmith, J. (2014). Nanoparticles in biotechnology, drug development and drug delivery [report]. bcc Research. Available at: http://bit.ly/2WCxjwa
8Tolfree, D. (2006). Commercialising nanotechnology, concepts-products-market. International Journal of Nanomanufacturing, volume 1, issue 1, pp.117–33.