Zameer

106

description

Nanotechnology presentation compiled by me n colleagues.

Transcript of Zameer

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(NDDS)

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Drug Delivery:

Drug delivery is the method or process of administering a pharmaceutical compound to achieve a therapeutic effect.

Drug delivery technologies that modify

Drug release profiles

Absorption

Distribution

Elimination

for the benefit of improving product efficacy, safety and patient convenience and compliance.

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Drug Delivery

Most common methods of delivery include the

Non-invasive per-oral (through the mouth) Topical (skin) Transmucosal (nasal, buccal/sublingual,

vaginal, ocular and rectal) Inhalation routes. Parental (IV, IM, IA, ISp etc)

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Novel drug delivery system

It is advance drug delivery system which improve

Drug potency Control drug release to give a sustained

therapeutic effect Provide greater safety Finally it is to target a drug specifically to

a desired tissue

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EXAMPLES OF NDDS

• Niosomes • Liposomes• Nanoparticles • Resealed

erythrocytes • Microspheres• Monoclonal

antibodies • Micro emulsions• Antibody-loaded

drug delivery• Magnetic

microcapsules• Implantable pumps

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Generation of Drug Delivery System

1st Generation 2nd Generation

3rd Generation

4th Generation

5th Generation

Tablet

Capsule

Ointment

Suspension

Emulsion

Suppositories

Repeat action tablet

Prolonged action tablet

Enteric Coated tablet

Timed Release tablet

Osmotically Control System

Swelling Controlled

Magnetic Controlled

System

Diffusion Controlled System

Targeted DDS

Modulated DDS

Self Regulated DDS

Gene Therapy

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TARGETED DRUG DELIVERYTargeted drug delivery, sometimes called

smart drug delivery A method of delivering medication to a

patient in a manner that increases the concentration of the medication in some parts of the body relative to others.

The goal of a targeted drug delivery system is to prolong, localize, target and have a protected drug interaction with the diseased tissue.

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Advantage of targeted drug delivery system over

traditional drug delivery system

Increased efficacy of the drug. Site specific delivery. Decreased toxicity/side effects. Increased convenience. Better patient compliance. Viable treatments for previously incurable

diseases.

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Targeted Drug Delivery

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An artificial microscopic vesicle consisting of an aqueous core enclosed in one or more phospholipid layers.

Used to convey vaccines, drugs, enzymes, or other substances to target cells or organs.

Liposome

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Liposome

Their exterior lipid bilayer is very chemically reactive, thereby providing a means to conveniently couple “tags” on a covalent basis. 

Such “tags” can be antibodies, antigens, cell receptors, nucleic acid probes, etc. 

This provides significant versatility in assay formats (i.e., immunoassay, receptor-based, nucleic acid probe, etc.) possible. 

With  diameters ranging in size from approximately 50 nm to 800 nm, their aqueous core encapsulates up to millions of molecules of signal generating “markers” that can be detected in a variety of different way. 

  

This provides significant versatility in the detection schemes possible.

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LiposomeA variety of different encapsulants are possible including visually detectable dyes (since the lipid bilayer is transparent), optically and fluorometrically detectable dyes, enzymes, and electroactive compounds. 

Spherical vesicles with a phospholipid bilayer

Hydrophilic

Hydrophobic

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Liposomes can be subcategorized

Small unilamellar vesicles (SUV), 25 to 100 nm in size that consist of a single lipid bilayer

Large unilamellar vesicles (LUV), 100 to 400 nm in size that consist of a single lipid bilayer

Multilamellar vesicles (MLV), 200 nm to several microns, that consist of two or more concentric bilayers

Vesicles above 1 µm are known as giant vesicles.

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1. Conventional Liposomes

Prepared form natural neutral and anionic lipids and have nonspecific interactions with their environment

Relatively unstable Have low carrying capacities Tend to be “leaky” to entrapped drug

substances .

Types of Liposomes

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Non-conventional Liposomes

Small sized, surface modified to overcome some of the short comings of conventional liposomes

Modified to reduce negative charge, decrease fluidity and cause steric hindrance to phagocytosis

Properties altered (e.g. by incorporation of cholesterol)

Polymerized liposomes more stable and less “leaky”

Types of Liposomes

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Uses of Liposomes

Chelation therapy for treatment of heavy metal poisoning

Enzyme Replacement

Diagnostic imaging of tumors

Study of membranes

Drug Delivery

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They can deliver agents directly into cells.

Routes: Intravenous (iv) Subcutaneous (sc) Intramuscular (im) Topical Pulmonary

Route of Liposomes in Drug Delivery

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Improved therapeutic response Achieve appropriate tissue or blood

levels Reduced adverse reactions

Less drug administered Targeted drug release

Lower dosing frequency Improved patient compliance Simpler dosing regimens Lower cost per dose

Advantages of Liposomes in Drug Delivery

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Doxil Daunorubicin 1995 Daunoxome Daunorubicin 1996

Ambisome Amphotericin B 1997

Depocyt Cytarabine 1999

Approved Liposome Products

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Niosomes

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Niosomes

Niosomes, non-ionic surfactant vesicles, are widely studied as an alternative to liposomes

These vesicles appear to be similar to liposomes in terms of their physical properties

They are also prepared in the same way and under a variety of conditions, from unilamellar or multilamellar structures.

Niosomes alleviate the disadvantages associated with liposomes, such as chemical instability, variable purity of phospholipids and high cost.

They have the potential for controlled and targated drug delivery

Niosomes enhanced the penetration of drugs

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Film Method Ether Injection Method Sonication Reverse Phase Evaporation Heating Method Microfluidization Multiple Membrane Extrusion Method Transmembrane pH gradient (inside acidic)

Drug Uptake Process (remote Loading) The “Bubble” Method Formation of Niosomes from Proniosomes

Methods of Preparations:

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Ophthalmic drug delivery Delivery of peptide drugs Immunological application of Niosomes Transdermal delivery of drugs by

Niosomes Delivery system for the vasoactive

intestinal peptide (VIP) Niosomes as carriers for Haemoglobin Niosomal vaccines Sustain release Localized action

Niosome Delivery Applications

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Niosomes as Drug Carriers Diagnostic imaging with Niosomes Drug Targeting

Delivery to the brain Anti cancer drugs Anti infectives

Targeting of bioactive agents To Reticulo-endothelial system (RES) To organs other than RES

Niosome Delivery Applications

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Role Of Polymer In ODDS.

Polymer Mucoadhesive Vehicle: Retained in the eye due to non-covalent bonding between with conjuctival mucine.

Mucine is capable of picking of 40-80 times of weight of water.

• 1. Inflow & Outflow of Lacrimal fluids.• 2. Efficient naso-lacrimal drainage.• 3. Interaction of drug with proteins of Lacrimal fluid.• 4. Dilution with tears.

Factors affecting intraocular bioavailability

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Classification of Ophthalmic Dosage Form

A) Based on Root of Administration• 1.Topical Soln:

Multiple Dose container With Preservatives.

• 2. Intra-ocular Soln:

For Surgery, Single dose, Without preservative.

• 3.Ophthalmic Soln

Injections: Intra-ocular injection, given in eye tissues, without preservative.

B) Based on Physical Form

• 1. Aqueous Soln.

• 2. Suspension.

• 3. Ointments.

• 4. Gels.

• 5. Eye Lotions.

• 6. Solid Inserts.

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Desired Criteria For Control Release Ocular Inserts:

ComfortEase of handlin

g

Reproducibility

of release kinetics

Sterility Stability Ease of mfg.

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Advantages 1. Accurate dosing.2. Absence of preservative.3. Increase in shelf life due toabsence of water.

Limitations• 1. Perceived by patient as

foreign body.• 2. Movement around the eye.• 3. Occasional loss during

sleep or while rubbing eyes.• 4. Interference with vision.• 5. Difficulty in placement &

removal.

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Types of Ocular Control Release SystemA) Non-Erodible1. Ocusert2. Contact Lenses.3. Diffusional Inserts

B) Erodible

1.Lacrisert. 2.SODI 3.Minidisc

C) Nanoparticle D) Liposome

Types:

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A) Non-Erodible :1.ocusert: Developed by Alza Corporation, Oval flexible ocular insert, Release Rate:20-40mg/hr

for 7day Consist of-

Annular ring : Impregnated with Ti02 : For Visibility

Part Material

Drug Reservoir PilocarpineCarrier material Alginic acidRate controller Ethylene vinyl acetate

copolymerEnergy Source Conc. Of PilocarpineDelivery Portal Copolymer membrane

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2) Contact Lens Presoaked Hydrophilic lens. Drug Release : within 1st 30 Min. Alternate approach : incorporate drug either as

soln or suspension of solid monomer mixture. Release rate is up to : 180 hr.

3) DIFFUSIONAL INSERTS : Central reservoir of drug enclosed in Semi

permeable or micro porous membrane for diffusion of drug.

Diffusion is controlled by Lacrimal Fluid penetrating through it.

It prevents continues decrease in release rate due to barrier.

Release follows : Zero Order Kinetics.

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B) Erodible Inserts1.Lacrisert:• Sterile, Rod Shaped device.• Composition: HPC without preservative.• Weight:5mg,• Dimension:Diameter:12.5mm, Length:3.5mm• Use:-Dry eye treatment, Keratitis Sica.

2.SODI: Soluble Ocular Drug Insert.• Small water soluble developed for Cosmonauts who

could not use their eye drop in liquid condition.• Composition : Acryl amide, Vinyl Pyrolidone,

Ethylacrylate.• Weight 15-16 mg. In 10-15 sec Softens; In 10-15 min. turns in Viscous Liquids; After 30-60min. Becomes Polymeric Solution.

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Advantages of SODI:

Single SODI application :replaces 4-12 eye drops Instillation, or 3-6 application of Ointments.

Once a day treatment of Glaucoma & Trachoma.

3)Minidisc: It is made up of counter disc with Convex front

& Concave back surface in contact with eye ball.

4-5mm in diameter. Composition : Silicon based pre polymer. Hydrophilic or Hydrophobic. Drug release from 170 hr.

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C) Nanoparticle:For water soluble drugs.

Size:10-1000nm

Drug is Dispersed, Encapsulated, or Absorbed

Produced by Emulsion Polymerization

• Chemical initiation, Gamma irradiation, Visible light.

Polymerization is carried out by :

Emulsifier stabilizes polymer particle

Polymer used are Biodegradable.

E.g. :- Nanoparticle of Pilocarpine enhances Mitotic response by 20-23%.

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“Nanotechnology is the art and science ofmanipulating matter at the nanoscale”

which is about 1 to 100 nanometers.

Nanotechnology

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 Proteins, glycoproteins, neo glycoproteins and artificial viral envelops (AVE); Glycosylated water-soluble polymers (poly-L-lysine) Mabs; Immunological Fab fragments; antibody enzyme complex & bispesific Abs; Toxins, immunotoxin & rCD4 toxin conjugates Lecithins (Con A) & polysaccharides.

Molecular Carriers:

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Introduction about Nanotechnology:

Nanotechnology is a broad interdisciplinary area of research, development and industrial activity.

NANOPARTICLES:Nanoparticles are the end products of a wide variety of physical, chemical and biological processes some of which are novel and radically different, others of which are quite commonplace.

Nanoparticles may be defined as submicron (<1µm) colloidal systems, generally, but not necessarily, made of polymers (biodegradable or not).

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Thus, this term the morphology and structural organization of the system.According to theis some what general, since it does not take into account process used for the preparation of Nanoparticles, Nanospheres or Nanocapsules can be obtained.

Nanocapsules are vesicular systems in which the drug is confined to a cavity surrounded by a unique polymeric membrane.

Nanospheres are matrix systems in which the drug is dispersed throughout the particles.

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GOALS:Control the particle size, surface properties and release of pharmacologically active agents in order to achieve the site-specific action of the drug at the therapeutically optimal rate and dose regimen.Difference between Liposomes and Nanoparticles:Liposomes Nanoparticles

Protecting drugs from degradation. Less targeting to site of action. Reduction toxicity or side effects. Low encapsulation efficacy. Rapid leakage of water soluble drug in the presence of blood components and poor storage stability.

Increase the stability of drugs. More targeting to site of action. Increase the encapsulation efficacy.Minimize the leakage of water soluble drug in the presence of blood components.

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Advantages of Nanoparticles: Particle size and surface characteristics of Nanoparticles can be easily manipulated to achieve both passive and active drug targeting after parenteral administration.

They control and sustain release of the drug during the transportation and at the site of localization

Subsequent clearance of the drug so as to achieve increase in drug therapeutic efficacy and reduction in side effects.

Drug Loading is relatively high and drugs can be incorporated into the systems without chemical reaction.

Site-specific targeting can be achieved by attaching targeting ligands to surface of particles.

The system can be used for various routes of administration including oral, nasal, parenteral, intra-ocular etc.,

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Preparation of Nanoparticles:Nanoparticles can be prepared from a variety of materials such as proteins, polysaccharides and synthetic polymers.The selection of this materials is dependent on many factors including: Size of Nanoparticles required. Inherent properties of the drug, e.g.: aqueous solubility and stability. Surface characteristics such as charge and permeability. Degree of biodegradability, biocompatibility and toxicity. Drug release profile desired. Antigenicity of the final product.

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Methods for Preparation of Nanoparticles:Nanoparticles have been prepared most frequency by three methods:

1.Dispersion of preformed polymers.2.Polymerization of monomers.3.Ionic gelation or Coacervation of hydrophilic

polymers.

Other methods such as,1.Supercritical Fluid Technology2.Particle Replication in Non-wetting

Templates (PRINT)

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Dispersion of Performed Polymers:Used to prepare biodegradable nanoparticles from

PLA, PLGA and PCA.This technique can be used in various ways such as1. Solvent Evaporation Method2. Spontaneous Emulsification or Solvent Diffusion

Method

Polymerization Method:In this method monomers are polymerized to form

nanoparticles in an aqueous solution.This technique has been reported for making Polybutylcyanoacrylate or Polyalkylcyanoacrylate nanoparticles.Nanocapsules formation and their particle size depends on the concentration of the surfactants and stabilizers used.

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Coacervation or Ionic Gelation Method:Much research has been focused on the preparation of nanoparticles using biodegradable hydrophilic polymers such as chitosan, gelatin and sodium alginate. Supercritical Fluid Technology:Supercritical Fluid Technology has been investigated

as an alternative to prepare biodegradable micro and nanoparticles because supercritical fluids are environmentally safe.

A supercritical fluid can be generally defined as a solvent at a temperature above its critical temperature, at which the fluid remains a single phase regardless of pressure.

Supercritical CO2 is the most widely used supercritical fluid because of its mild critical conditions, non-toxicity, non-flammability and low price.

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Applications of Nanoparticulate Delivery Systems:1. Tumor targeting using nanoparticulate delivery

systems.

2. Reversion of multidrug resistance in tumor cells.

3. Nanoparticles for oral delivery of peptides and proteins.

4. Targeting of nanoparticles to epithelial cells in the GI tract using ligands.

5. Nanoparticles for gene delivery.

6. Nanoparticles for drug delivery into the brain.

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Nanoparticles for Drug Delivery:

Metal-based nanoparticles

Lipid-based nanoparticles

Polymer-based nanoparticles

Biological nanoparticles

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Nanobiopharmaceuticals

In biopharmaceuticals, in addition to the main technologies covered-liposomal, monoclonal antibody-based, and polymer-based technologies host of newer technologies such as nanoparticles including various nanodimensional entities such as molecular imprinted polymers, metallofullerenes, pro-drug delivery, oral, injectable and implantable, pulmonary, and transdermal and transmucosal delivery have come up.

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Drug Delivery Technology Important to Pharma Industry

Drug delivery formulations involve low cost research compared that for discovery of new molecule,

Minimizing the drug use would significantly reduce the effective cost of drug which would give financial relief to the patients,

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Delivery systems increase commercial opportunity by distinguishing a drug from competitive threats posed by “me too” drugs and

Novel means of delivery particularly using nano-carriers, can allow branded drugs to be rescued from abyss of generic competition (may be called “resurrection of drug”).

Drug Delivery Technology Important to Pharma Industry

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Some significant achievements of nanodevices Development of one dose a day

ciprofloxacin using nanotechnology

Tumor targeted taxol delivery using nanoparticles in Phase 2 clinical trial stage

Improved ophthalmic delivery formulation using smart hydrogel nanoparticles

Oral insulin formulation using nanoparticles carriers.

Liposomal based Amphotericin B formulation

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Drug Delivery Carriers

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Targeting Ligands

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Nanopowder:

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Nanopowder Nanopowders are powders composed of

nanoparticles, that is particles having an average diameter below 50 nanometers (nm).

A jar of a true nanopowder when emptied from chest height to toward the floor will disperse into the air before reaching the floor.

Most manufacturers of “nanopowders” produce micropowder assemblies of nanoparticles but the powder itself is rarely a nanopowder.

Such compounds have two or more different cations (positively charged elements) in their chemical formula. An example of a complex compound is calcium titanate (CaTiO3).

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Nanocluster:

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Nanocluster:

One of the central themes in nanoscience research is to synthesize high quality nanoparticles with precise control over particle size, shape, structure, and composition.

For inorganic nanoparticles (e.g. metal and semiconductor), two regimes are of particular interest, that is, nanoclusters in a size range from subnanometer to ~2 nm and nanocrystals (typically 2-100 nm).

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Nanocrystals

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Nanocrystals

When the size of the material is reduced to less than 100 nanometers, the realm of quantum physics takes over and materials begin to demonstrate entirely new properties.

Nano-design of drugs by various techniques like milling, high pressure homogenization, controlled precipitation etc., are explored to produce, drug nanocrystals, nanoparticles, nanoprecipitates, nanosuspensions (which for ease of understanding commonly mentioned as nanocrystals).  

As decreased size will increase the solubility of drugs hence, this technology is explored to increase oral bioavailability of sparingly water soluble drugs.

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Micelle

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Micelle Micelle is an aggregate of amphipathic molecules in water,

with the nonpolar portions in the interior and the polar portions at the exterior surface, exposed to water.

Amphiphilic molecules form micelle above a particular concentration which is called as critical micellar concentration (CMC).  

Micelles are known to have an anisotropic water distribution within their structure, means  water concentration decreases from the surface towards the core of the micelle, with a completely hydrophobic (water-excluded) core.

Hydrophobic drugs can be encapsulated/solubalized, into inner core.

The spatial position of a solubilized drug in a micelle will depend on its polarity, nonpolar molecules will be solubilized in the micellar core, and substances with intermediate polarity will be distributed along the surfactant molecules in certain intermediate positions.  

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Dendrimers

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Dendrimers

These branched macromolecules are constructed around a simple core unit.

Dendrimers have a high degree of molecular uniformity, narrow molecular weight distribution, specific size and shape characteristics, and a highly- functionalized terminal surface.

The manufacturing process is a series of repetitive steps starting with a central initiator core. Each subsequent growth step represents a new "generation" of polymer with a larger molecular diameter, twice the number of reactive surface sites, and approximately double the molecular weight of the preceding generation.

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Polymeric Nanoparticles

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Polymeric Nanoparticles In recent years, biodegradable polymeric

nanoparticles have attracted considerable attention as potential drug delivery devices in view of their applications in drug targeting to particular organs/tissues, as carriers of DNA in gene therapy, and in their ability to deliver proteins, peptides and genes through a per oral route of administration.

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Carbon 60

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Carbon 60

C60 are spherical molecules about 1nm in diameter, comprising 60 carbon atoms arranged as 20 hexagons and 12 pentagons: the configuration of a football.

Hence they find application as NanoPharmaceuticals with large drug payload in their cage like structure.

On the other hand with development of various chemical substitutes for C60, it is possible to develop functionalized C60 with better drug targeting properties

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Carbon Nanotube

Carbon nanotubes are adept at entering the nuclei of cells and may one day be used to deliver drugs and vaccines.

The modified nanotubes have so far only been used to ferry a small peptide into the nuclei of fibroblast cells.

But the researchers are hopeful that the technique may one day form the basis for new anti-cancer treatments, gene therapies and vaccines.

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Equipments for Nanoparticles

1.Homogenizer

2.Ultra Sonicator

3.Mills

4.Spray Milling

5.Supercritical Fluid Technology

6.Electrospray

7.Ultracentrifugation

8.Nanofiltration

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Methods of Drug Delivery

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 1.Medicine2.Energy i) Reduction of energy consumption ii) Increasing the efficiency of energy production iii) The use of more user friendly energy systems3.Information and Communication4.Heavy Industries i) Aerospace ii) Refineries iii) Vehicle manufactures

Fields using Nano Technology

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Nanotechnology in Medicine

Drug Delivery Therapy techniques Anti – Microbial Techniques Diagnostic Tissue Engineering

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Nanotechnology in MedicineDRUG DELIVERY - Employing nanoparticles to deliver

drugs. - Oral administration of drugs.

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THERAPY TECHNIQUES - Buckyballs - Nanoshells - Nanoparticles - Aluminosilicate Nanoparticles - Nanofibers

Nanotechnology in Medicine

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ANTI-MICROBIAL TECHNIQUES - Nanoparticle Cream - Nanocapsules

- Cell repairs using Nanorobots

Nanotechnology in Medicine

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i) Nanotechnology-on-a-chip is one more dimension of lab-on-a-chip technology.

ii) Magnetic nanoparticles, bound to a suitable antibody, are used to label specific molecules, structures or microorganisms.

i i i ) Gold nanoparticles tagged with short segments of DNA can be used for detection of genetic sequence in a sample.

Diagnostics

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i) Nanotechnology can help to reproduce or to repair damaged tissue.

ii) “Tissue engineering” makes use of artificially stimulated cell proliferation by using suitable nanomaterial-based scaffolds and growth factors.

iii) Tissue engineering might replace today’s conventional treatments like organ transplants or artificial implants. Advanced forms of tissue engineering may lead to life extension.

Tissue Engineering

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Applications of Nanoparticles to Drug Discovery and Biology

Fluorescent biological markers Detection of proteins Probing of DNA structures MRI contrast enhancement Separation and purification of biological

molecules and cells Tumor destruction via heating Tissue engineering Drug and gene delivery

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Tree-like polymers, branching out from a central core and subdividing into hierarchical branching units

- Not more that 15 nm in size, Molecular Weight very high.

- Very dense surface surrounding a relatively hollow core (vs. the linear structure in traditional polymers)

Dendrimers

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Courtesy of: http://www.uea.ac.uk/cap/wmcc/anc.htm

In 2008 there were over 10 000 scientific

reports and 1000 patents dealing with

dendritic structures.

Dendrimers

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Dendritic Family

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Structural Components of Dendrmers

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Drugs

Drug delivery : Small molecules Proteins Tissue targeting

Drug solublization

RNA/DNA delivery

Diagnostics & materials applications

Applications in Pharmaceutical Industry

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Improved efficacy of drugs Extension of drug half-life Reduced toxicity Active or passive targeting Product lifecycle management Improved solubility of drugs Drug “rescue”

Applications in Drug Delivery

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Utilizing a dendrimer construct the aqueous solubility of the drug Paclitaxel was increased >9,000X.

Paclitaxel aqueous solubility 0.8 mg/mL

Improved Drug Solubility

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Dendrimers are particularly attractive as they offer a high drug-loading capacity.

2 methods of dendrimer drug delivery are

Encapsulation of drugs Dendrimer –drug conjugates

Mechanism of drug delivery: Dendrimer

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Interactions between the dendrimer and drug to trap the drug inside the dendrimer.

Such a system can be used to encapsulate drugs and provide controlled delivery. 

,e.g: DNA was complexed with PAMAM dendrimers for gene delivery applications, and hydrophobic drugs and dye molecules were incorporated into various dendrimer cores.

Mechanism of drug delivery: Dendrimer

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Dendrimer–Drug Conjugates In dendrimer–drug conjugates, the drug is attached through a covalent bond either directly or via a linker/spacer to the surface groups of a dendrimer.

Dendrimers have been conjugated to various biologically active molecules such as drugs, antibodies, sugar moieties and lipids

Mechanism of drug delivery: Dendrimer

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The drug loading can be tuned by varying the generation number of the dendrimer

Release of the drug can be controlled by incorporating degradable linkages between the drug and dendrimer

Conjugates of PAMAM dendrimers with cisplatin, a potent anticancer drug with non-specific toxicity and poor water solubility.

The conjugates show increased solubility, decreased systemic toxicity and selective accumulation in solid tumors

Mechanism of drug delivery

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Drugs Delivered Through Dendrimers

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Micelle Micelles are like tiny balls of molecules.

They are made out of amphipathic molecules.

An amphipathic molecule is a molecule that is both hydrophilic (polar) and hydrophobic (non-polar).

A micelle is a ball that forms when amphipathic molecules are put in a liquid. The liquid can be polar (like water) or non-polar (like butane or octane).

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Micelles Shape

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Stepwise growth model (Isodesmic model)

Closed aggregation modelStepwise growth model (Isodesmic model)Aggregation is a continuous process broad aggregation, no CMC

Micelle formation mechanism

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OH

H

O

HH

OH

H

Surfactant Micelle

Hydrophilic

Hydrophobic

OH

H

O

HHO

HH

O

H

H

OH

H

OH

H

H2O

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Miclle as Drug Carrier

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Miclle as Drug Carrier

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Summary & Conclusion- From being a theory to something we can now see,

words turned into reality.

- Nanotechnology has evolved over the period of time for many decades, and is now showing its potential to the whole world.

- The development of nanomachines such as: I-switch, nanoimpellers, nanobots etc.

- Nanotechnology will increase your standard of living.

- Up to today nanotechnology is what's in, what's new, and what's the latest technology being developed all over the world.

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Creativity is allowing oneself to make mistakes.

Art is knowing which one to keep.

Thank You..!!