NANO-TECHNOLOGY FOR HEALTH

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1 NANO-TECHNOLOGY FOR HEALTH Alfred Cuschieri Institute for Medical Science and Technology Division of Surgery and Cancer University of Dundee & School of medical sciences Scuola Superiore S Anna, Pisa

2 NANOTECHNOLOGY MARKETS

3 NANOTECHNOLOGY Nanotechnology multidisciplinary field that covers diverse array of technologies derived from engineering, physics, chemistry, materials science and biology Burgeoning field has led to rapid advances in technology and life and physical sciences Ushered new era of Nano-Medicine with nanomaterials designed to interact with the body at subcellular molecular scales with a high degree of specificity Potential for targeted cellular and tissue-specific clinical applications designed to achieve maximal therapeutic efficacy with less side effects

4 NANOSCALE One nanometre (nm) = one thousand millionth of a meter For comparison, a single human hair = 80,000nm and an RBC = 7,000 nm Definition of nanoscale: from 100nm down to the size of atoms (approximately 0.2nm) At this scale the properties of materials are very different from those at a larger scale

5 UNIQUE PROPERTIES OF MATERIALS AT THE NANOSCALE Nanomaterials have relatively larger surface area when compared to bulk materials - more chemically reactive - some materials are inert and become reactive in their nanoscale Nanoscale affects the strength and/ or electrical properties Quantum effects begin to dominate the behaviour of materials affecting their optical, electrical and magnetic properties

6 NANOTECHNOLOGY & NANOSCIENCE: STUDY OF MATTER AT AN ATOMIC AND MOLECULAR SCALE Richard Feynman in 1959: at nano scale the gravity would become less important, surface tension and van der Waals attraction predominate highly reactive quantum effects

7 NANOMEDICINE Nanotechnology in drug delivery Nanotechnology in gene delivery MRI contrast and molecular imaging Antibacterial agents Nano-fluidic diagnostic chips Nano-formulations of established chemotherapeutic anti-cancer agents Nanohyperthermic ablation Control of cell movement: regeneration and regenerative medicine Nano-molecular imprinting polymers to replace monoclonal antibodies Nano-piezoelectric transducers therapies based on electric stimulation

8 PGLA and PLA NANOPARTICLES for DRUG DELIVERY and as GENE THERAPY VECTORS Because of their sustained-release characteristics Biocompatibility Biodegradability Ability to protect DNA from degradation in endolysosomes

9 NON-VIRAL TRANSFECTION by PGLA NP Polymeric NPs of PGLA are able to escape rapidly from the endolysosomal compartment to the cytoplasm following intracellular uptake and thus the carrier-dna complex escape lysosomal digestion The transfection yield correlates negatively with size of PGLA PLA particles such that 100nm particles produce the highest transfection rate The higher transfection efficiency of the smaller fraction not related to the differences in the DNA loading, cellular uptake, or DNAs release

10 QDs which rely on bioluminescence resonance energy transfer - able to convert chemical into photonic energy, with greatly increased fluorophore excitation and reduction in the effects of tissue autofluorescence Need for biocompatible QDs to overcome the innate toxicity of heavy metal QDs which require complex polymer encapsulation for biocompatibility ADVANCES IN QUANTUM DOTS

11 NANOTECHNOLOGY FOR IMAGING Nanotechnologies enabled intracellular imaging through attachment of QDs or synthetic chromophores to selected molecules or by the incorporation of natural fluorescent proteins with optical techniques such as confocal microscopy Nanosensors based on fluorescence resonance energy transfer (FRET) which uses QDs linked to DNA probes. In this system, a fluorescence resonance energy transfer donor-acceptor ensemble forms as a result of the binding of the target strand to a dye labelled reporter strand

12 CELLULAR IMAGING by QDs Human breast cancer cells tagged with quantum dots Fluorescence microscopy of labelled chromosomes

13 LIPOSOMES Small spherical artificial vesicles produced from natural nontoxic phospholipids and cholesterol Liposomes are particularly useful as gene therapy vectors because of their ability to pass through lipid cell membrane Likely to replace viral vectors, especially cationic liposomes Form complexes (lipoplexes) and are increasingly preferred for the intracellular delivery of reporter or therapeutic genes because of high transfection rates

14 DENDRIMERS Dendrimers - macromolecular compounds consisting of a series of branches around an inner core Dendritic polymers are effective as DNA conjugates Resulting dendrimer-dna complex differs from encapsulation in as the mechanism responsible for gene retention consists of electrostatic interactions between the negatively charged phosphate DNA groups and the positively charged amino groups on the polymer Polyamidoamines (PAMAMs) are the most often used and effective dendrimers for gene delivery

15 EU NANOTECHNOLOGY PLATFORM EU Definition of Nanomedicine: Nanomedicine is defined as the application of nanotechnology to achieve breakthroughs in healthcare. It exploits the improved and often novel physical, chemical and biological properties of materials at the nanometer scale. Nanomedicine has the potential to enable early detection and prevention, and to essentially improve diagnosis, treatment and follow-up of diseases

16 EU NANOTECHNOLOGY PLATFORM Nanomedicine should aim for meaningful improvements in areas that contain the most severe challenges in future healthcare Six disease areas selected based on the following criteria: diseases that reduce QoL high prevalence impose a high socio-economical burden on society nanotechnology predicted to have high impact on the care process for: Cardiovascular disease, Cancer, Musculoskeletal disorders, Neurodegenerative and Psychiatric disorders, Diabetes, Bacterial and viral infections

17 POTENTIAL of NANOTECHNOLOGY IN DRUG THERAPY Controlled drug delivery Targeted drug delivery Reduced drug toxicity Theranostic disease management

18 NANOTECHNOLOGY FOR MOLECULAR DIAGNOSTICS NANO CHIPS vs BIOCHIPS Nanochips and nanoarrays Constructed with microelectromechanical system (MEMS) Nanotechnology is being used to overcome some of the limitations of biochip technology Biological tests measuring the presence or activity of selected substances are made quicker, more sensitive, and more flexible when certain nanoscale reagent particles are used Detection of specific biomolecular interactions Magnetic nanoparticles, bound to a suitable plastic nano-antibodies are used to label specific molecules

19 POTENTIAL of NANOTECHNOLOGY on a CHIP Nanotechnology plastic antibodies on a chip is a new paradigm for total chemical analysis systems The ability to make chemical and biological information much cheaper and easier to obtain is expected to fundamentally change: health care food safety crime detection/ law enforcement

20 NANO-ONCOLOGY Incidence of cardiac events Congestive Heart failure Free doxorubicin 29% 8% Myocet 13% 2% Journal of Nanomaterials Volume 2011 (2011), Article ID , C Riggio, E Pagni, V Raffa, A Cuschieri

21 NANO-ONCOLOGY with LIPOSOMAL FORMULATIONS Table 3: Values for half-life and AUC for two liposomal formulations and free doxorubicin. Half-life time AUC (Area Under Curve) Free doxorubicin 0.2 h 4 μgh/ml Myocet 2.5 h 45 μgh/ml Caelyx/Doxil 55 h 900 μgh/ml Journal of Nanomaterials Volume 2011 (2011), Article ID , C Riggio, E Pagni, Va Raffa, A Cuschieri

22 WIRELESS ELECTRO STIMULATION THERAPY BY PIEZO- ELECTRIC NANOSTRUCTURED IMPLANT Stereotactic injection video Deep brain stimulation (DBS) of subthalamic nucleus for Parkinson s disease D

23 n-molecular IMPRINTING POLYMERS SOLUBLE PLASTIC ANTIBODIES HEL machine for thin film University of Dundee Schematic representation of the automated synthesis of nanomips using an immobilised template

24 BIOLOGICS THERAPY with n-mip PLASTIC ANTIBODY against EGFR EQUIVALENT TO HERCEPTIN extracellular and transmembrane domain interfaces in epidermal growth factor receptor signalling

25 CONFOCAL MICROSCOPY STUDIES OF TUMOUR CELLS WITH PEGYLATED n-mips Confocal microscopy of HaCaT cells treated with 2.5 nm PEGylated n-mips. Staining agents: DAPI (blue) for the nucleus, DIO (green) for the cytoplasm, and Rhodamine (red) for nanomips

26 HYBRID QD-nMIP against VEGFR

27 ZEBRA FISH EMBRYO TUMOUR XENOGRAFT STUDIES with QD-MIP IMPRINTED against hvegf QD-MIPs imprinted against hvegf injected in WM-266 zebrafish embryos 80 WM-266 cells Distance of QD-MIPs from WM-266 cells (um) Embryo#1 Embryo#2 Embryo#3 Embryo#4 Embryo#5 Embryo#6

28 CONTROL - QD-NIP imprinted against vancomycin QD-NIPs imprinted against vancomycin injected in WM-266 zebrafish embryos 400 Distance of QD-NIPs from WM-266 cells (um) WM-266 cells 0 Embryo#1 Embryo#2 Embryo#3 Embryo#4 Embryo#5 Embryo#6

29 CONTROL XENOGRAFT with TUMOUR CELLS not expressing VEGFR QD-MIPs imprinted against hvegf injected in A375 zebrafish embryos 700 A375 cells no VEGF expression Distance of QD-MIPs from A375 cells (um) Embryo#1 Embryo#2 Embryo#3 Embryo#4 Embryo#5 Embryo#6

30 Mean of the distances nanoprobe-cells in zebrafish embryos injected with either WM-266 or A375 cells HOMING of anti-vegfr QDn-MIP ONLY to XENOGRAFTS EXPRESSING VEGFR (266 cells) Distance nanoprobe-cells mean (um) QD-MIP WM-266 ** *** QD-nip WM-266 QD-MIP A375

31 LOW COST BIOLOGICS THERAPY WITH nmips EGFR n-mips binding to lung and breast cancer cells

32 n-mips vs. MONOCLONAL ANTIBODIES Major resistance to introduction of n-mips in cancer therapy and from some of the funding bodies Difficult to defend because of the obvious advantages of n-mips over mabs: Far cheaper to produce - greatly reduced therapeutic costs to NHS Long shelf life Greatly improved biodistribution Likely oral bio-availability No allergic issues

33 RISK of n-materials to HUMAN HEALTH Although some concerns may be ill-founded, the toxicology of many nanomaterials has not yet been fully evaluated EU Companies are participating in the European Nanosafe Consortium - evaluates the possible risks from manufacture and use of nanomaterials When inhaled nanomaterials reach the lungs with subsequent possible spread to other organs At the cellular level, ability to act as a gene vector has been demonstrated for NPs Experimental evidence which demonstrates that DNA can wrap around CNT, raising some concerns over adverse consequences of CNTs after entering the human body

34 CONCLUSIONS Nanomedicine based on nanoscience/ engineering, biology and material science has the potential to improve healthcare It will result in more effective therapies for a wide spectrum of human disorders: genetic, common life threatening and neurodegenerative Usher new approaches to currently untreatable disorders Lead to cheaper and more effective pharmaceuticals with reduced side effects Need for robust scientific studies on the toxicity and harzards on nanomaterials and the adoption of required protective measures

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36 MICROPARTICLES, NANOPARTICLES, APTAMERS Colloidal micro particles > 100nm 1000nm Nanoparticles are colloidal particles < 100nm Aptameres 4-10nm size: DNA, RNA, and peptide aptamers function as direct antibodies against any molecular target - small molecules, toxins, peptides, proteins, viruses, bacteria etc. Aptamers exhibit high specificity and affinity strong binding to their specific targets - they structurally conform to bind to their targets, when compared with antibodies, which require antigens and epitopes Binding of aptamer to specific target does not cause an immune response