drug delivery systems using nanotechnology

1. RECENT ADVANCES IN NANO
DRUG DELIVERY SYSTEMS
M ROSHINI
13PN02

3. Targetted Drug Delivery

4. Nano Drug-delivery
• Nanomedicine uses nanoscale technologies (≤100 nm) for the
diagnosis, treatment and/or prevention of diseases
• It includes sustained delivery of
Therapeutic Agents,
Targeted Delivery Of Drugs
Reduced Side Effects

5. Drug delivery carriers

6. Nanoparticles in drug delivery
• Metal-based nanoparticles – Au, Ag, Cd-Se, Zn-S
etc
• Lipid-based nanoparticles – Liposome & Neosome
based….
• Polymer-based nanoparticles – Dendrimer,chitosen
Micelle based…
• Biological nanoparticles – RGD based…

8. Gold Nanoparticles
• Plasmonic Vesicles of Amphiphilic Gold Nanocrystals: Self-Assembly
and External-Stimuli-Triggered Destruction
• Plasmonic vesicular nanostructures assembled from amphiphilic
gold nanocrystals with mixed polymer brush coatings.
• Analogous to block copolymers,the disruption of the plasmonic
vesicles can be triggered by stimulus mechanisms
• The development of multifunctional vesicles containing stimuli-
responsive polymers applications in theragnostic nanomedicine

9. Self-Assembly and External-Stimuli-
Triggered Destruction

10. Thermal ablation of cancer cells by
‘Silica-gold’ nano shells
• Thermal ablation of cancer cells by nanoshells coated with metallic layer and
by applying an external energy source to kill them
• Gold nps absorb light in the near infra red region becomes hot and can kill
the cells in their proximity

12. Liposomes
• Liposomes are small spherical vesicles, composed of lipid bilayers surrounding
aqueous inner phase.
• Reservoir (i.e) Bilayers - hydrophobic drugs and inner aqueous phase - hydrophilic
drugs
• Liposomes -ocular drug delivery
• Encapsulation of idoxuridine into liposomes increased the corneal penetration of
the drug
• Variety of biomaterials for ocular drug delivery including
 polymeric nanoparticles
 dendrimers
 hydrogels

16. Lipid Nanoparticle Drug Delivery System
• Major problem with IV administration of colloidal particles is interaction with
reticulo-endothelial system (RES)
• Any foreign material, biological response to administered nanoparticle, coated by
proteins called opsonins, enhance uptake of coated material by RES
• Opsonins on particle surface creates a “molecular signature” recognized by
immune cells
• Lipid nanoparticles engineered to evade RES cells by limiting particle sizes to 200
nm or less.
• It is believed that these cells do not recognise low nanometer-sized particles as
foreign.

18. Drug Delivery To BBB
• The BBB is single layer of endothelial cells in inner surfaces of capillaries
in the brain
• The endothelial cells fit tightly together and substances cannot pass out of
the bloodstream
• The mechanism for transport is endocytosis
• Endothelial cells with lipoprotein receptor transports the lipoprotein with
nanoparticle from the blood plasma.

21. Polymeric Nanoparticles On Drug Delivery
• Polymeric nps from natural and synthetic polymers have stability and ease
of surface modification
• Polymeric materials-biocompatible and biodegradable
• The polysaccharides polymeric materials to prepare nps for drug delivery.
• Biodegradable nanoparticles
nanocapsule
nanosphere
• The drug molecules are either entrapped inside or adsorbed on the surface.

23. Chitosan Carrier In Nano Drug Delivery
System
• Chitosan (CS) is abundant naturally occurring polysaccharide
• Chitosan is made of randomly distributed β-(1-4)-linked D-glucosamine (deacetylated unit)
and N-acetyl-D-glucosamine (acetylated unit)
• It is produced by deacetylation of chitin extracted from shells of crabs, shrimps and krill.
• Chitosan attracted as
 Matrix for controlled release due to its reactive functionalities
 Easily degradation by enzymes
 Non-toxic degradation products
• Hydrophobic interactions enhance stability of substituted CS by reducing hydration of matrix
,resisting degradation by gastric enzymes

24. Polymeric Nanoparticles On Drug Delivery
Chemical Structure Of Chitosan

26. TREATING CANCER WITH NANOPARTICLES
• Cancer therapeutics,chemotherapy serious side effects –
Devastation of healthy tissue
Some cancerous tissue survives after radiation
• Nanoparticles -targeted drug delivery systems
• Nps with UV-sensitive proteins,assemble with drug and cancer cell-
targeting protein fragment when exposed to UV.
• Nanoparticle-drug complex that specifically attaches to cancerous cells.

28. Reference
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and the EPR effect in macromolecular therapeutics: a review. J. Controlled Release 65, 271-84.
• [2] Palmer, T. N., Caride, V. J., Caldecourt, M. A., Twickler, J., and Abdullah, V. (1984) The
mechanism of liposome accumulation in infarction. Biochim. Biophys. Acta 797, 363-8.
• [3] Jaracz, S., Chen, J., Kuznetsova, L. V., and Ojima, I. (2005) Recent advances I tumortargeting
anticancer drug conjugates. Bioorg. Med. Chem. 13, 5043-54.
• [4] Torchilin, V. P. (2004) Targeted polymeric micelles for delivery of poorly soluble drugs. Cell
Mol. Life Sci. 61, 2549-59.
• [5] Gabizon, A., Shmeeda, H., Horowitz, A. T., and Zalipsky, S. (2004) Tumor cell targeting of
liposome-entrapped drugs with phospholipid- anchored folic acid-PEG conjugates. AdV. Drug
DeliVery ReV.56, 1177-92.