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The future of nano-devices in medicine
Matthew Hockley, studying BSc Biomedical Science (Hons), Level 2
The University of Lincoln
Introduction
Nano-devices today are still thought by many as sci-fi fiction but advances
over the past 20 years have started becoming non-fiction. Many advances
have been made into nanomedicine for application in the medical arena in
particular nanoparticle and biomarkers for drug delivery as well as self-assembling nanotechnology.
A combination of both nanoparticles for drug delivery and self- assembling nanotechnology could be
the building blocks for a future nano-robot device to act independently by administering xenobiotics
or other treatments to target specific health problems in the human body.
Nanoparticles in drug delivery are currently being developed with a promising role in medicine with
improvements in localisation and specificity of drugs. Furthermore, developments into passing drugs
across the blood-brain barrier are being developed. Other promising developments in nanoparticles
have been designed to deliver other payloads such as light or heat which can aid in diagnosis and
treatment and applications in gene delivery.
Research into self-assembling nanotechnology is becoming more popular but is still very much in the
developing stages. There are currently two proposed approaches to carrying out self-assembly which
are the arrangements of independent atoms and molecules into a specific structure or self-assembly
using biological molecules such as DNA and proteins (Muir et al., 2011).
Nanoparticles in drug delivery
Nanoparticles offer more advantages over common drugs by protecting premature degradation of
drugs, releasing drugs to react in the localised area in the body, enhancing absorption therefore
increase bioavailability and control of the pharmacokinetic profile (Peer et al., 2007). Development
of nanoparticles has been designed for a variety of different medical conditions over the past few
years where applications are proposed to cure HIV and many different types of cancers. A list below
shows examples of different nanocarrier drugs on the market.
Compound
PEG-L-asparaginase
Commercial Name
Oncaspar
Nanocarrier
Polymer-protein
complex
Immunotoxin (fusion
protein)
Chemoimmunoconjugate
Indications
Acute Lymphoblastic
leukemia
Cutaneous T-cell
lymphoma
Acute myelogenous
leukemia
IL-2 fused to diphtheria
toxin
Anti-CD33 antibody
conjugated to
calicheamicin
Anti-CD20 conjugated
to yttrium-90 or
indium-111
Ontak (Denilelukin
diftitox)
Mylotarg
Zevalin
Radioimmunoconjugate
DaunoZome
Abraxane
Liposomes
Albumin-bound
paclitaxel nanopartical
Relapsed or refractory,
low-grade, follicular, or
transformed nonHodgkin’s lymphoma
Kaposi’s sarcoma
Metastatic breast
cancer
Daunorubicin
Paclitaxel
Table adapted from Peer et al. (2007)
Of the current 10 nanocarriers included in the global market study of nanocarriers by Cientifica
(2013), 45% of nanocarriers were composed from gold nanocarriers and liposomes.
As well as carrying drugs, nanoparticles can deliver other toxins which could not normally be used.
An example is from a recent study which has shown a possible prevention and cure for strains CXCR4
and CCR5 tropic HIV-1 using nanoparticles loaded with melittin, bee venom (Hood et al., 2013).
Furthermore, this application used for HIV-1 prevention could be applied to additional viruses such
as hepatitis B and C due to action in a similar method.
Nanoparticles have been designed for delivering DNA or RNA to specific tissues and cells. A study
carried out in 2008 showed the capabilities of using DNA to cause suicide of epithelial ovarian cancer
cells in mice (Sawicki et al., 2008). With capabilities to modify cells to proliferate or to undergo
apoptosis, a nano-scaled device will need to adapt to a given medical condition such as different
types of cancer by possibly undergoing self-assembly.
Self-assembling nanotechnology
Development of self-assembly in nanotechnology has improved over the past years with many
different possibilities for applications in medicine. Self-assembly can be one of two methods which
are mechanosynthesis or manipulation of existing biological components such as DNA and proteins.
Mechanosynthesis is where molecular assemblers are used to construct anything from materials to
biological proteins using atoms or molecules. The use of mechanosythesis is still theoretical but
applications have been suggested using carbon-carbon dimer placement tool given the family name
of DCB6-X (Merkle and Freitas, 2003).
Compared to mechanosynthesis, self-assembly using biological components has had applications in
laboratories with many different uses currently in-development. The most common type of
biological components used is proteins where C-terminal and N-terminal are utilised for electrostatic
self-assembly (Ji and Shen, 2005). Research has shown that using a gold nanoparticle smaller than
15nm can be used as the building block for encapsulation using self-assembling protein
nanoparticles which is promising for developing biomedical devices (Yang and Burkhard, 2012).
Developments combining two separate protein chains using a short synthetic peptide to form a
complex have shown to have applications in the medical arena combining proteins to form an active
neurotoxin drug such as botulinum (Ferrari et al., 2011; Ferrari et al., 2012). Nanoparticles have
been further designed to control self-assembly of cytoskeletal structures in the body by use of
magnetic nanoparticles coated with proteins which are important for control of mitosis and cell
migration (Kumar, 2013).
Conclusion
To conclude, currently there is a lot of research that still requires development till nano-devices
which can work independently in the body become common place in hospitals. With more funding
being dedicated to nanotechnology, advances in nanomedicine are soon going to increase with ever
growing applications and replicate the success of biotechnology.
The applications of nanoparticles is growing with interest from pharmaceutical companies funding
more towards developing nanoparticles for drugs which have a better bioavailability and allow more
control over pharmacokinetic of a drug. The uses of nanoparticles are slow appearing to market
currently due to lack of funding for clinical trials.
Development into self-assembly are still in the distant future but with current developments using
stapling techniques and methods for constructing structures, nano-devices that can self-assemble
may appear sooner than expected. Self-assembly is only half the challenge when the self-assembly
requires a certain shape or structure to cause an affect which, depending on the method used will
require a lot of work and engineering.
Currently, nano-devices consist of implants used for detecting cancer and sensors to diagnose a
medical condition. An example of an implanted nano-device is a sensor to confirm a myocardial
infarction by detecting three cardiac marker peptides which are cTnl extravasation, Myoglobin
extravasation and CK-MB extravasation (Ling et al., 2011).
References
Cientifica Ltd. (2012) Nanotechnology for Drug Delivery: Global Market for Nanocarriers [Online]
Available from: http://www.marketresearch.com/Cientifica-Ltd-v2574/Nanotechnology-DrugDelivery-Global-Nanocarriers-6856624/ [Accessed 20th March 2013]
Ferrari, E., Maywood, E.S., Restani, L., Caleo, M., Pirazzini, M., Rossetto, O., Hastings, M.H., Niranjan,
D., Schiavo, G., and Davletov, B. (2011) Re-assembled botulinum neurotoxin inhibits CNS functions
without systemic toxicity. Toxins, 3(4), pp. 345-355.
Ferrari, E., Soloviev, M., Niranjan, D., Arsenault, J., Gu, C., Vallis, Y., O'Brien, J., and Davletov, B.
(2012) Assembly of protein building blocks using a short synthetic peptide. Bioconjugate Chemistry,
23(3), pp. 479-484.
Hood, J.L., Jallouk, A.P., Campbell, N., Ratner, L., and Wickline, S.A. (2013) Cytolytic nanoparticles
attenuate HIV-1 infectivity. Antiviral Therapy, 18(1), pp. 95-103.
Ji, J. and Shen, J. (2005) Electrostatic Self-assemble and Nanomedicine. Conference Proceedings :
...Annual International Conference of the IEEE Engineering in Medicine and Biology Society.IEEE
Engineering in Medicine and Biology Society.Conference, 1, pp. 720-722.
Kumar, S. (2013) Microtubule assembly: Switched on with magnets. Nat Nano, 8(3), pp. 162-163.
Ling, Y., Pong, T., Vassiliou, C.C., Huang, P.L., and Cima, M.J. (2011) Implantable magnetic relaxation
sensors measure cumulative exposure to cardiac biomarkers. Nat Biotech, 29(3), pp. 273-277.
Merkle, R.C. and Freitas, R.A.,Jr (2003) Theoretical analysis of a carbon-carbon dimer placement tool
for diamond mechanosynthesis. Journal of Nanoscience and Nanotechnology, 3(4), pp. 319-324.
Muir, N.C., Dudley, D., and Peterson, C. (2011) Nanotechnology For Dummies. Wiley. pp. 85-87
Peer, D., Karp, J.M., Hong, S., Farokhzad, O.C., Margalit, R., and Langer, R. (2007) Nanocarriers as an
emerging platform for cancer therapy. Nature Nanotechnology, 2(12), pp. 751-760.
Sawicki, J.A., Anderson, D.G., and Langer, R. (2008) Nanoparticle delivery of suicide DNA for
epithelial ovarian cancer therapy. Advances in Experimental Medicine and Biology, 622, pp. 209-219.
Yang, Y. and Burkhard, P. (2012) Encapsulation of gold nanoparticles into self-assembling protein
nanoparticles. Journal of Nanobiotechnology, 10, pp. 42-3155-10-42.