Med-Tech Innovation Nanotechnology
Figure 1: These images show CdTe quantum dots of between 2.5 and 5 nm in size as the colour changes from green to red (left to right).
Images supplied by Professor Yurii Gun`ko, Ms Valerie Gerard and Professor John Donegan 2,3
nanomedicine, to name a few. To put it in perspective, one nanometre is 10-9
metres, that is one billionth of a
metre. A human hair is approximately 50,000 nm in width and one nanoparticle is approximately one million times smaller than the full stops used in this article. Figure 1 shows the range of colours available for nanoparticles of cadmium telluride (CdTe) of different diameters. These particles are small semiconducting crystals known as quantum dots, which can absorb a range of colours depending on their size. Nanoparticles are being used in a variety of applications including as excellent dyes for biological applications.
Nanoresearch in Ireland In Ireland, nanoscience underpins major sectors of the economy. In 2007, Ireland exported €13.2 billion in goods, of which it is estimated 10% were enabled by nanoscience and related technologies. Ireland is already home to fifteen of the world’s top twenty medical device manufacturers. Nanotechnology is fast becoming one of the most important areas in the advancement of technology in this industry. The Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) at Trinity College Dublin, which operates in partnership with University College Cork, is recognised internationally as a leading institute for nanoscience research and collaborative industry engagement. CRANN is funded through Science Foundation Ireland (SFI) and has more than 250 researchers. It works at the frontiers of research in nanoscale chemical, physical and biological phenomena, with a particular focus on medical device and sensor technologies. CRANN researchers publish more than 150 peer review articles annually. A Thomson-Reuters report in late 2010 placed Ireland eighth globally for materials science research based on citations per publication for the decade 2000 to 2010. CRANN researchers were responsible for more than 70% of the outputs associated with this national ranking. CRANN’s industry engagement has grown significantly during the past two years. Through the support of SFI, Enterprise Ireland, European Union and Higher Education Authority research funding, as well as industrial support from companies such as Hewlett-Packard and Intel, CRANN offers industry access to leading research
www.med-techinnovation.com
facilities. Its new Advanced Microscopy Laboratory houses many of the world’s most advanced microscopy tools for examination of materials on the atomic scale. These tools include the only helium ion microscope (HeIM) in Ireland and one of only approximately one dozen in the world. The HeIM has recently been used to image uncoated mammalian cancer cells for the first time yielding a wealth of information about cell surfaces.2 Many exciting nano-enabled medical devices are being developed at CRANN. One area has been the development of micron-sized sensors for use with micro- organisms such as Methicillin-resistant Staphylococcus aureus (MRSA), which if detected later than 72 hours after infection can become resistant to treatment. Unlike traditional methods of detection, which may take hours or overnight incubation, the CRANN sensors can detect growth of just a few micro-organisms within minutes. Other work includes the evaluation of the diagnostic and therapeutic potential of nanoparticles, development of bar-coded nanowires for multiplexed detection of bio- markers molecules for disease, and nanoscale coatings for medical devices and biological applications.
Surfaces
Understanding how materials work and react with the body at the nano level will revolutionise medical devices and CRANN is helping companies to get a closer look at the surfaces that matter. From stents to artificial joints, it is the surface layer of the medical device that interacts with the body and/or biofluids. In a matter of milli- or micro- seconds biomolecules will adhere to implanted surfaces and it is this vital initial interaction and interfacial layer that will determine an implanted device’s ultimate success. Nanoscience is at the forefront of this dynamic interfacial layer formation because nanostructures are generally smaller than cells, which range in size from 10,000 to 20,000 nm.3
Cells can interact specifically with nano-
textured surfaces and in particular to ordered symmetries, because they have inherent features that can detect this nanotopography.4
Nanofeatures may help to influence
which cells will adhere and thrive on a surface. A focal point of CRANN’s current research is the
production of nanostructured surfaces for enhancing the capabilities of medical devices. For decades, it had been noted that adding texture to implants increased
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