Nanogel

An overview of nanogel drug delivery system it contains the information about gel & nanogel ,mechanism & routes of nanogel administration etc . Its very useful when studing the novel drug delivery system. It is also useful during formulation of Nanogel.

1. Prepared By
Mr. M. D. Birajdar
M. Pharm Final Year
An Overview of Nanogel Drug
Delivery System
Guided By
Dr. S. G. Gattani
Professor & Director
School of Pharmacy, S.R.T.M.U.,Nanded.
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2. CONTENTS
1.Introduction of Gel
2.What is Nano & Nanogels ?
3.Mechanism of drug release
4.Application of Nanogel
5.Criteria for selection of Drug for Nanogel
6.Selection of Polymer, Gelling Agent ,Excipients
7.Present status on Nanogel
8.Patent on Nanogel
9.Marketed formulation
10.References
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3. Gel:
Introduction:
A gel is a cross-linked polymer network swollen in a liquid
medium.
The U.S.P. defines gels as a semisolid system consisting of
dispersion made up of either small inorganic particle or
large organic molecule enclosing and interpenetrated by
liquid.
A gel consists of a natural or synthetic polymer forming a
three dimensional matrix throughout a dispersion
medium or hydrophilic liquid.
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4. CLASSIFICATION OF GELS
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5. 1. Inorganic hydrogels are two-phase systems, such as
aluminium hydroxide gel and bentonite magma.
2.Organic gels are single-phase systems and may include
such gelling agents as carbomer and tragacanth and those
that contain an organic liquid, such as Plastibase.
3.Hydrogels include ingredients that are soluble in
water;they include organic hydrogels, natural and synthetic
gums, and inorganic hydrogels. Ex. hydrophilic colloids
such as silica, bentonite, tragacanth,pectin, sodium
alginate, methylcellulose ,carboxymethylcellulose sodium.
4.Organogels include the hydrocarbons, animal and
vegetable fats, soap base greases, hydrophilic organogels.
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6. What is Nanotechnology?
Nanotechnology is the science and technology of small things  in
particular things that are less than 100nm in size.  One
nanometer is 10-9 meters.
What is Nanogel?
The term ‘nanogels’ defined as the nanosized particles
formed by physically or chemically crosslinked polymer
networks that is swell in a good solvent.
The term “nanogel” was first introduced to define cross-linked
bifunctional networks of a polyion and a nonionic polymer for
delivery of polynucleotides (cross-linked polyethyleneimine
(PEI) and poly (ethylene glycol) (PEG).
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7. Properties of Nanogels:
1.Biocompatibility and degradability
2.Swelling property in aqueous media
3.Higher drug loading capacity
4.Particle size
5.Solubility
6.Colloidal stability
7.Non-immunologic response
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8. Classification of Nanogel:
 The first classification is based on their responsive
behavior, which can be either stimuli-responsive or
nonresponsive.
1. In the case of non-responsive nanogels, they simply
swell as a result of absorbing water.
2. Stimuli-responsive nanogels swell or deswell upon
exposure to environmental changes such as temperature, pH,
magnetic field, and ionic strength. Multi-responsive
microgels are responsive to more than one environmental
stimulus
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9.  The second classification is based on the type of
linkages present in the network chains of gel structure,
polymeric gels divided in 4 types:
1.Physical cross-linked gels
2.Liposome Modified Nanogels
3.Micellar Nanogels
4.Hybrid Nanogels
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10. Mechanism of drug release from
Nanogels:
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11. 1.Diffusion
Example: The diffusional release of doxorubicin from
stable hydrogel nanoparticles based on pluronic block
copolymer This release mechanism is simple and has been
successfully employed in various nanomedicines.
2.Nanogel degradation
3.Displacement by ions present in the environment
4.Others
 Photochemical internalization and
photoisomerisation
Excitation of photosensitizers loaded nanogels leads to
production of singlet oxygen and reactive oxygen species
which cause oxidation of cellular compartment walls such as
endosomal barrier walls which effects release of therapeutics
into cytoplasm.
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12. FORMULATION DESIGN :
Gel forming agent or Polymer:
 Molecular weight, chemical functionality of polymer
must allow diffusion and release of the specific drug.
The polymer should permit the incorporation of a
large amount of drug.
 The polymer should not react, physically or
chemically with the drug.
 The polymer should be easily manufactured and
fabricated into the desired product and inexpensive.
It should be stable & Non toxic.
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13. No single material may have all these attributes, certain excipients
may be incorporated to alter some properties for example Co-
solvents such as ethanol, propylene glycol, PEG 400 could be
added to increase drug solubility.
Gel forming polymers are classified as below:
a) Natural Polymers:
I.Proteins – E.g. Collagen, Gelatin, Xanthin, Gellum Gum
II.Polysaccharides – E.g. Agar, Alginic acid, Sodium or potassium
carrageenan, Tragacanth, Pectin, Guar Gum, Cassia tora
b) Semisynthetic Polymers
I. Cellulose Derivatives – E.g. Carboxymethyl cellulose
Methylcellulose, HPC, HPMC,HEC.
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14. c) Synthetic Polymers
I.Carbomer – E.g. Carbopol -940, Carbopol -934,Carbopol -941
II. Poloxamer
III. Polyacrylamide
IV.Polyvinyl Alcohol
V.Polyethylene and its copolymers
d) Inorganic Substances – E.g. Aluminium Hydroxide,bentonite
e) Surfactants – E.g. Cetosteryl alcohol, Brij-96
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15. Routes of Administration:
 Oral
 Pulmonary
 Nasal
 Parenteral
 Intra-ocular
 Topical
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16. Synthesis of Nanogel :
Photolithographic techniques
 Fabrication of biopolymers
 Water-in-oil (W/O) heterogeneous emulsion methods
 Inverse (mini) emulsion method
 Micromolding method
 Reverse micellar method
 Membrane emulsification
 Chemical cross linking
 Carbodiimide coupling
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17. Heterogeneous free radical polymerization
 Precipitation polymerization
 Dispersion polymerization
 Inverse (mini) emulsion polymerization
 Inverse microemulsion polymerization
 Heterogeneous controlled/living radical polymerization
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18. Selection criteria of Drug substance
for Nanogels:
1. Physicochemical properties
 Drug should have a molecular weight of less than 500 Daltons.
 Drugs highly acidic or alkaline in solution are not suitable for
topical delivery.
 Drug must have adequate lipophilicity.
 A saturated aqueous solution of the drug should have a pH value
between 5 and 9.
2. Biological properties
The drug should not be directly irritated to the skin.
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19. Drugs, which degrade in gastrointestinal tract or are
inactivated by hepatic first pass effect, are suitable for topical
delivery.
Tolerance to the drug must not develop under the near zero
order release profile of topical delivery.
The drug should not stimulate an immune reaction in the
skin.
 Drugs which have to be administered for a long time or
which cause adverse effects to non-target tissue can also be
formulated for topical delivery.
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20. Applications of Nanogel:
1.Cancer: Cancer treatment involves targeted delivery of
drugs with expected low toxicities to surrounding tissues and
high therapeutic efficacy.
2.Autoimmune disease
3.Opthalmic
4.Diabetics : An Injectable Nano-Network that Responds to
Glucose and Releases Insulin has been developed. It contains
a mixture of oppositely charged nanoparticles that attract
each other. Glucose molecules can easily enter and diffuse
through the gel. Thus when levels are high, lots of glucose
passes through the gel and triggers release of the enzyme that
converts it to gluconic acid. This increases acidity,
which triggers the release of the insulin.
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21. 5.Neurodegenerative
 Nanogel is a promising system for delivery of
ODN(godeoxynucleotides) to the brain.
 Nanogels bound or encapsulated with spontaneously
negatively charged ODN results in formation of stable
aqueous dispersion of polyelectrolyte complex with particle
sizes less than 100 nm which can effectively
transported across the BBB.
6.In stopping bleeding
 A nanogel composed of protein molecules in solution
has been used to stop bleeding.
7.Anti-inflammatory action
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22. Present status of Nanogels:
•Nanogels are promising and innovative drug delivery
system that can play a vital role by addressing the
problems associated with old and modern therapeutics such
as nonspecific effects and poor stability.
• Nanogels appear to be excellent candidates for brain
delivery.
•One future goal of research in this area should be the
improved design of microgels/nanogels with specific
targeting residues to enable highly selective uptake into
particular cells.
•This will be especially important for the targeting of cancer
cells, thereby reducing non-specific uptake into healthy
cells.
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23. Patents on Nanogels:
1.Carrier based nanogel formulation for skin targeting.
Publication number.: WO 2012176212 A1
2.Nanogels for cellular delivery of therapeutics
US 8361510 B2
3.Nanogels for cellular delivery of therapeutics
US 8361510 B2
4.Cationic Nanogels For Biotechnological
Applications
US 20130072576 A1
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24. Marketed Formulations:
1.Zyclin Nanogel
2.Adalene nanogel
3.Oxalgin nanogel
4.Zyflex nanogel
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25. References:
1.Topical Gels as Drug Delivery Systems: A Review
by Ashni Verma*, Sukhdev Singh, Rupinder Kaur,
Upendra K Jain Chandigarh College of Pharmacy,
Landran, Mohali, Punjab, India, Int. J. Pharm. Sci.
Rev. Res., 23(2), Nov – Dec 2013.
2.An Overview of Nanogel Drug Delivery System by
Farhana Sultana*, Manirujjaman School of Health
Science, Department of Pharmacy, State University
of Bangladesh, Journal of Applied Pharmaceutical
Science Vol. 3 (8 Suppl 1), pp. S95-S105,
September, 2013
3.www.google.co.in
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26. 4.Alexander V. Kabanov and Serguei V. Vinogradov. 2008.
Nanogels as Pharmaceutical Carriers, Multifunctional
Pharmaceutical Nanocarriers, Springer Science, New
York, 67-80.
5.www.google.co.in/patents/ US 20130072576 A1
6.www.google.co.in/patents/ WO 2012176212 A1
7.www.google.co.in/patents/ US 8361510 B2
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