This document discusses novel nasal drug delivery systems, specifically mucoadhesive in situ gels. It begins with an introduction to nasal drug delivery and its advantages over other routes of administration such as avoiding first-pass metabolism and rapid drug absorption. It then discusses the mechanisms of drug absorption through the nasal cavity, including both paracellular and transcellular transport. Mucoadhesive in situ gels are highlighted as a promising nasal drug delivery approach as they form a gel once administered in the nasal cavity, potentially increasing bioavailability by prolonging drug release and residence time. The document concludes by noting that while nasal delivery has benefits, it is limited to smaller volume and higher molecular weight compounds may not be suitable for this route.

1. Submitted to:-
Dr. SUNIL KUMAR PRAJAPATI
( PROF. )
Institute of pharmacy
Bundelkhand university
Jhansi.
Submitted by:-
Surya prabhakar singh
M. Pharma 2nd semester
Institute of pharmacy
Bundelkhand university
Jhansi.
NOVAL NASAL DRUG DELIVERY
SYSTEM

2. CONTENT
 INTRODUCTION
 DRUG INSTILLATION TO NASAL CAVITY
 COMPARSION OF NASAL WITH OTHER DRUG DELIVERY SYSTEM
 ANATOMY AND PHYSIOLOGY OF NOSE
 NOSE BRAIN PATHWAY
 FUNCTION
 MECHANSIM OF DRUG ABSORBTION
 FACTOR AFFECTING
 VARIOUS NASAL DRUG DELIVERY FORMULATION
 APPLICATION
 EVALUTION
 CURRENT STUDY
 MUCOADESIVE IN SITU GELS NOVEL DRUG
 ITS MECHANISM
 NOVEL MUCOADHESIVE
 FUTURE DEVELOPMENT IN NASAL DOSAGE FROM DESIGN
 CHITOSAN
 NOVAL NASAL DEVICES FOR THE EFFICIENT DRUG DELIVERY
 CONCLUSION
 REFERENCE

3. INTRODUCTION
 Nsal cavity is one of the best method for delivering the drug it has faster and
higher drug absorption.
 By this method we can avoid first pass metabolism
 Nasal route is an alternative to invasive administration and provides a direct
access to the systemic circulation.
HISTORY
 The history of nasal drug delivery dates back to earlier topical applications of
drugs intended for local effects. Nasal therapy also called 'Nasya karma' has been
recognized form of treatment in the Ayurvedic system of Indian medicines.
 The early 1980 the introduction of nasal route as a promising systemic delivery
alternative to other conventional drug delivery routes.

4.  Total surface area of nasal cavity is 160cm²(microvilli included)
 Total volume 16-19ml
 3 regions- vestibular, turbinate (respiratory), olfactory region
 Vestibular region- Mainly filters airborne particles
 Olfactory region- capable of metabolizing drug, smell receptors.
 Turbinate region- Drug absorption is optimal
Anatomy and physiology of nose

5. Fig:2 Cell types of the nasal epithelium
showing ciliated cell (A), non-ciliated cell(B),
goblet cells(C), gel mucus layer (D), sol layer
(E), basal cell (F) and basement membrane
(G)
Fig:1 Parts of nasal cavity consists of nasal
vestibule, inferior turbinate, middle
turbinate, superior turbinate & Olfactory
neurons.

6. DRUG INSTILLATION TO NASAL CAVITY

7. COMPARISON OF NASAL WITH OTHER DRUG
DELIVERY SYSTEM
parameters nasal oral parenteral Transdermal
BBB and csf
bypass
yes no no No
Rapid onset yes no yes Yes
Pain at site of
administration
no no yes no
Self
administration
yes yes no yes
Patient
compliance
high high low moderate
Hepatic first
pass
metabolism
no yes no no

8. ADVANTAGE
 Drug degradation that is observed in the gastrointestinal tract is absent.
 Hepatic first pass metabolism is avoided.
 Rapid drug absorption and quick onset of action can be achieved.
 The bioavailability of larger drug molecules can be improved by means of
absorption enhance or other approach.
 The nasal bioavailability for smaller drug molecules is good.
 Drugs that are orally not absorbed can be delivered to the systemic circulation by
nasal drug delivery.
 Nasal route is an alternate to parental route, especially, for protein and peptide
drugs
 Drugs possessing poor stability in g.i.t. fluids are given by nasal route.
 Polar compounds exhibiting poor oral absorption may be particularly suited
for this route of delivery system

9. DISADVANTAGE
 The histological toxicity of absorption enhancers used in nasal drug
deliverysystem is not yet clearly established.
 Relatively inconvenient to patients when compared to oral delivery
systemssince there is a possibility of nasal irritation.
 Nasal cavity provides smaller absorption surface area when compared
toGIT.
 Certain surfactants used as chemical enhancers may disrupt and
even dissolvethe membrane in high concentration.
 There could be a mechanical loss of the dosage form into the other
parts ofthe respiratory tract like lungs because of the improper
technique ofadministration.

10. A- ciliated cells
B- non-ciliated cells
C- Goblet cells
D- Gel mucus layer
E- sol layer
F- Basal cell
G- Basement membrane
• Mucocilliary clearance:
Particles entrapped in the mucus layer are transported with it thus, effectively cleared
from the nasal cavity. The combined action of mucus layer and cilia is
called mucociliary clearance. This is an important, nonspecific physiological defence
mechanism of the respiratory tract to protect the body against noxious inhaled
TYPES OF CELLS IN NASAL EPITHELIUM

11.  Warms and humidifies inspired air
 removes and traps pathogens and particulate matter from inspired air sense
of smell drains and clears lacrimal ducts
FUNCTIONS OF NASAL CAVITY
COMPOSITION- 95% water, 2 % mucin, 1% salts, 1% of proteins such
as albumin, immunoglobulins, lysozyme and lactoferrin, and 1% lipids .
NASAL SECRETIONS
• Viscosity
• Solubility
• Diurnal variation
• pH - pH of formulation should be between 4.5 to 6.5 for better absorption.

13. MECHANISMS OF ABSORPTION
• First step in the absorption of drug from the nasal cavity is passage
through the mucus.
• Subsequently absorption may occur via: transcellular & paracellular.
• Paracellular route :
• Slow and passive. Inverse log-log correlation b/w intranasal absorption
and molecular wt. of water-soluble compounds.
• Drugs also cross cell membranes by an active transport route via carrier
mediated means or transport through the opening of tight junctions.

14. MECHANISM OF DRUG ABSORPTION

15.  First mechanism:
 It involves an aqueous route of transport, which is also known as the
paracellular route but
 slow and passive.
 There is an inverse log-log correlation between intranasal absorption and the
molecularweight of water soluble compounds.
 The molecular weight greater than 1000 Daltons show poor bioavailability 8.
 Second mechanism:
 It involves transport through a lipoidal route known as the transcellular
process.
 It is responsible for the transport of lipophilic drugs that show a rate
dependency on their lipophilicity.
 Drugs can also cross cell membranes by an active transport route via carrier-
mediated means or transport through the opening of tight junctions.
 example - chitosan, a natural biopolymer from shell fish opens tight junctions
betweenepithelial cells to facilitate drug transport

16. FACTORS AFFECTING NASAL DRUG
ABSORPTION

17. FACTORS AFFECTING NASAL DRUG
ABSORPTION
Drug concentration:
Absorption depends on the initial concentration of the drug The absorption
follows first-orderkinetics.
pH at absorptionsite:
• Nasal absorption is pH dependent .Nasal pH in nasal secretion of adult :
5.5-6.5. In infants and children: 5- 6.7.It becomes alkaline in conditions such
as acute rhinitis, acute sinusitis.
• Lysozyme in the nasal secretion helps as antibacterial and its activity is
diminished in alkaline pH.
Particlesize:
 Particle size 10-50 microns adheres best to the nasal mucosa.
 Smallerparticles pass on to the lungs, larger particles form droplets
and run-out of thenose.

18.  Relative lipid solubility
As lipid solubility increases, permeation increases, so lipid
soluble drugs are completely absorbed
 MUCOSAL CONTACT TIME
viscosity increases contact time which increases the
permeation of thedrug
 MOLECULAR WEIGHT OF THE DRUG
Higher the molecular size, lower the nasal absorption. A
good systemic bioavailability can be achieved for
molecules with a molecular weight of up to 1000 Daltons
when no absorption enhancer is used.

19. MECHANISMS FOR DRUG ABSORPTION
ENHANCEMENT
• Mainly used for drugs with high water solubility.
• Water soluble drugs poor permeability across nasal epithelia
insufficient bioavailability.

20. COLLOIDAL CARRIERS IN NOSE TO BRAIN DRUG
DELIVERY SYSTEM

21. Particulate drug delivery
LIPOSOMES
• Advantage - effective encapsulation of small & large molecules with
wide range of hydrophilicity & pKa.
• Increasing nasal retention of peptides.
• Protection of the entrapped peptides from enzymatic degradation.
MICROSPHERES
• Microspheres are usually based on muco-adhesive polymers
(chitosan, alginate).
• Protect the drug from enzymatic metabolism and sustain drug
release.
NANOPARTICLES
• Adjuvant in vaccines or as drug carriers, in which the active
substance is dissolved, entrapped, encapsulated, adsorbed or
chemically attached.

22. FORMULATION

23. Drugs commonly used are
 β2-adrenergic agonist: terbutaline sulphate.
 Corticosteroids : budesonide.
 Anti cholinergic: ipratropium bromide .
 Mast cell stabilizer : sodium chromogylate.
VISCOSIFYING AGENTS
 These agents increase the viscosity of the solution prolonging the
therapeutic activity of preparation. e.g.: hydroxypropyl cellulose.
SOLUBILIZERS
 Aqueous solubility of drug always a limitation for nasal drug
delivery. e.g.: glycol, alcohol, labrasol, transcutol.
 In such cases surfactants or cyclodextrines (HP-β -cyclodextrine)
are used , these serve as a biocompatible solubilizer & stabilizer in
combination with lipophilic absorption enhancers.

24. SURFACTANTS
Modify the permeability of nasal mucosa & facilitate the nasal
absorption of drugs. E.g. SLS, Poly acrylic acid, sod.glycocholate.
BIOADHESIVE POLYMERS
Increases the residence time of drug in nasal cavity and a higher local
drug concentration in the mucus lining on the nasal mucosal surface.
E.g.: Methylcellulose, Carboxymethylcellulose Hydroxyl propyl cellulose
PRESERVATIVES
These are used to prevent the growth of micro organisms.
e.g.: parabens, benzalkonium chloride, phenyl ethyl alcohol, EDTA etc.
ANTIOXIDANTS
These are used to prevent drug oxidation.
E.g.: sodium meta bisulphite , sodium bisulfite, butylated hydroxy
toluene& tocopherol etc.

25. DOSAGE FORMS

26. Nasal drops
 Most simple and convenient systems developed for nasal delivery.
 It has been reported that nasal drops deposit human serum albuminin the nostrils
more efficiently nasal sprays.
 Simplest delivery system
 Delivered with pipette or squeeze bottle
 Mainly used for treatment of local conditions.
 Disadvantage- lack of the doseprecision.

27. NASAL SPRAY
 More accurate then drops.
 Consist of chamber, piston and actuator.
 Both solution and suspension can be formulated into nasal sprays.
 Can deliver an exact dose from 25 to 200μl.
 They can be unidose, bidose or multidose
 Deliver an exact dose from 25 to 200μm.

28. NASAL GEL
They are highly viscous thickened solutions or suspension
Advantages:
 • Reduction of post-nasal drip .
 • Reduction of taste impact due to reduced swallowing.
 • Reduction of leakage of formulation
NASAL POWDER
This type of dosage form is developed if solution and suspension dosage
form cannot be developed due to stability issue
Advantages
 • Absence of preservaties
 • Stability of formulation

29. MAD ( Mucosal Atomization Device )
The MAD ( Mucosal Atomization Device )will deliver a mist of atomized
medication that is absorbed directly into your patient's blood stream
avoiding first-pass metabolism.
• The atomized nasal medications absorb directly into the brain and
cerebrospinal fluid via olfactory mucosa to nose-brain pathway.
• It achieves medication levels comparable to injections.

30. NASAL VACCINES
• Especially against respiratory
infections.
• IgG and IgA.
• May be important against HIV and
Hepatitis B virus.
• Live attenuated influenza vaccine
(FluMist) – Nasal Spray Suspension.
(adenovirus‐vectored influenza,
group B meningococcal native,
attenuated respiratory syncytial virus
and parainfluenza 3 virus).

31. Application of nasal drug delivery system
Delivery of non-peptide pharmaceuticals
Drugs with extensive pre-systemic metabolism .
Ex- progesterone, propanolol
• Delivery of peptide based pharmaceuticals
Ex-Insulin, hormones.
• Delivery of diagnostic drugs
Ex-Secretin- for pancreatic disorder
Pentagastin- for secretory function of gastric acid
• Delivery of drugs to brain
It has been reported for brain tumors, sleep disorder and pain
• Systemic delivery
Ex-analgesics (morphine), antiviral drugs.

32. • For nasal powders:
Particle size, melting point, angle of repose, carr’s compressibility index
etc.
• For nasal gels:
Mucoadhesive strength, flow properties, etc
• For nasal sprays-
Content drug delivery, sterilization
• For nasal drops-
Clarity test, sterilization, etc.
Evaluation for nasal drug delivery

33. In-vitro studies
• Nasal permeation studies:
Ussing Chamber’
(Han’s chamber):
 • Chamber consists of u shaped Tubing system usually made of Glass,
filled with experimental solution.
 • Barrier used are excised nasal mucosa from rat or rabbits.
 • Drug solution is introduced into mucosal side of chamber and
samples were collected from receiver chamber.

35. • Rat model:
Procedure :
• Incision is made in the neck of rat and the
trachea is cannulated with a polyethylene
tube.
• Passage of nasopalatine tract is sealed to
prevent drainage of drug solution through
nasal cavity to mouth.
• Drug is delivered through nostrils and blood
Sample is collected from femoral vein.
Since all possible outlets in rat model is
blocked, the only possible pathway or drug to
be absorbed into systemic circulation is
diffusion through nasal mucosa.
In vivo nasal absorption studies

36. RABBIT MODEL
 The rabbit is anaesthetized by an intramuscular injection of
a combination of ketamine and xylazine.
 The rabbit's head is held in an upright position and the
drug solution is administered by nasal spray into each
nostril.
 During the experiment the body temperature of the rabbit
is maintained at 37°C with the help of a heating pad.
 The blood samples are collected by an catheter in the
marginal ear vein or artery.

37. mucoadhesive in situ
gels
– NOVAL NASAL DRUG
DELIVERY SYSTEM

38. • The use of nasal cavity as a route of administration of
drugs, specifically systemically acting drugs that pose a
delivery challenge, have become an area of great
interest.
• In situ forming polymeric formulations are drug
delivery systems
administration in
that are in sol form
the nasal cavity, but
before
once
administered, undergo gelation in situ, to form a gel.
• This presentation will gives us an overview of how
mucoadhesive in situ gels as a promising approach for
nasal drug delivery system.

39. • Results in higher bioavailability thus use lower doses of
drug.
• Results in rapid absorption and onset of action.
• Easily accessible, non-invasive route.
• Avoids degradation of drug in GIT resulting from acidic or
enzymatic degradation.
compounds cannot be• High molecular weight
delivered through this route.
• Volume that can be delivered into nasal cavity is
restricted to 25 –200 µl.

40. • It involves an aqueous route of
transportation.
• The absorption here is slow.
• It is also known as the
paracellular route.
First
Mechanism
• It involves a lipoidal route of
transportation.
• Drug cross cell membranes by an
active transport route via carrier-
mediated means or transport through
the opening of tight junctions.
• It is also known as the transcellular
process.
Second
Mechanism

41. Mucoadhesion is a state in which two materials, one of which is
biological in nature, are maintained together for a prolonged time
period by means of interfacial forces.
• The mucoadhesives spread over
the substrate to initiate close
contact & increase surface
contact, promoting the diffusion
of its chains within the mucus.
• Attraction and repulsion forces
arises for a mucoadhesive to be
successful.
• Mechanism of mucoadhesion are
of two steps :
 Contact stage
 Consolidation stage

42. Mucoadhesive Carrier
Internal Absorption
Interaction with Mucus
Hydration & Swelling of Polymers
Drug Release
Hydrophilic Macromolecular Drug
Ciliary Clearance Enzymatic Metabolism

43. Gels
• Gel is the state which exists between solid and liquid
phase.
• The solid component comprises a three dimensional
network of inter-linked molecules.
In-Situ Gel Delivery System
• It is a process of gel formation at the site of action
after the formulation has been applied at the site.
• The phenomenon based upon liquid solution of
drug formulation and converted into semi-solid
mucoadhesive key depot.

44. • Increased residence time of drug in nasal cavity.
• Low dose required.
• Results in rapid absorption and onset of effect.
• The nasal in-situ gel follows phase transition
mechanism and to stand with the shear forces in the
nasal cavity wall.
• Nasal in-situ gel should have long residence time.
• It should be of low viscosity.

45. They can be classified under:
IN SITU
FORMING
HYDROGELS
In situ gel
formation based
on physiological
stimuli
Thermally
triggered
pH triggered
In situ gel
formation based
on chemical
reactions
Ionic cross
linking
Photo-
polymerization

46. A. Thermally triggered
• Three main strategies exist for thermally triggered system :
• Negatively thermo-sensitive have lower critical solution
temperature (LCST).
• positively thermo-sensitive have upper critical solution
temperature (UCST).
• Thermo-reversible gels are made from Pluronics.
• All the pH-sensitive formations contain acidic or basic
groups that either accept or release protons which is
triggered by the change in environmental pH.

47. A. Ionic Cross-linking
• Polymers may undergo phase transition in presence of
various ions
• k-carrageenan forms rigid, brittle gels in replacement of
small amount of K+ while i-carrageenan forms elastic gels
mainly in the presence of Ca2+ ion.
• Alginic acid undergoes gelation in presence of divalent/
polyvalent cations.
• A solution of monomers or reactive macromers and
initiator can be injected into a tissue site and an
electromagnetic radiation used to form gel.
• Acrylate or similar functional groups undergo photo-
polymerization in the presence of suitable photo initiator.

48. 1. Measurement of gelation temperature and gel
melting.
2. Gel-strength.
3. Viscosity and rheology.
4. Evaluation of the mucoadhesive strength.
5. In vitro drug diffusion.
6. In vitro permeation studies.

49. 1. Lectins
• Lectins are carbohydrate-
binding proteins, macromolecules
that are highly specific for sugar
moieties.
• Lectins have the ability to stay on
the cell surface .
• Lectins allow target specific
attachment & also act as a means
of delivering the drug through a
controlled process to the cells .

50. mucoadhesiveare
having side chains
• Thiomers
polymers
carrying thiol
formation of
which lead to
covalent bonds
between the cystiene groups in
the mucus and the polymer by
simple oxidation process.
• Thiolated polymers display in situ
gelling properties due to the
oxidation of thiol groups at
physiological pH-values resulting in
the formation of intermolecular
and intramolecular disulfide
bonds.
of
• This increases the
theviscosity
formulation
increasing
thereby
the
residence time of the
product tremendously.
2. Thiomers

51. 3. Alginate Poly-Ethylene Glycol Acrylate
• Alginate-PEGA has an
withalginate backbone
acrylated polyethylenglycol
groups attached to it.
• It is known to undergo ionic
sol to
(gelation)
gel transition
upon interaction
with multivalent ions such as
Ca2+, Fe2+.
these three
moieties of
• Combining
functional
Alginate Polyethylene
glycol Acrylate leads to
an improved novel
polymer which can be
used mucoadhesive
nasal drug delivery.

52. 4. Poloxamer (Pluronics)
• Poloxamers are made non-ionic difunctional triblock
copolymers containing a centrally located hydrophobic
polypropylene oxide between hydrophilic polyethylene
oxides.
• Poloxamers have thermoreversible property which
convert from a liquid to a gel at body temperature,
thus, causing in situ gelation at the site of interest.
• Poloxamers are also known as Pluronics.
• Pluronics have been chemically combined with poly
(acrylic acids) to produce systems with enhanced
adhesion and retention in the nasal cavity. E.g.:
Poloxamer 407 (Pluronic F127) .

53. • Mucoadhesive
offers better
efficiency,
nanoparticles
encapsulation
enhanced
biocompatibility control release &
has less toxic properties.
• Polymeric mucoadhesive NP with
improved sinus mucus
penetration capability which may
lead to the development of new
generations of nanoparticle based
intranasal drug delivery
systems.
1. Mucoadhesive Nanoparticles

54. 2. Bacterial Adhesion
• The attachment of
synthetic/natural macromolecules
to mucus or epithelial surface is
defined as bioadhesion.
• Bacteria are capable of adhering to
the epithelium surface with aid of
fimbriae, which are long, lectin-
like proteins found on the surface
of many bacterial strains.
• The adhesion of bacteria to
epithelial surfaces is used as an
efficient method for nasal drug
delivery with the intention of
reducing mucociliary clearance.

55. 3. Altered Amino Acid Sequence
• Certain amino acid sequences
can be used to promote binding
of drug molecules to specific cell
surface glycoproteins due tothe
amino acids
complementary
having
sequences
present to these glycoproteins.
• In certain disease conditions the
sequence of glycoproteins is
altered.
• This altered state can be used as
a target by complementary
amino acid sequences by
attaching them to a drug delivery
device.

56. 4. Antibody mechanism
• Antibodies can be a rational
choice as a polymeric ligand for
site-specific
due to their
designing
mucoadhesives
high specificity.
• Antibodies can
against selected
be produced
molecules
present on mucosal surfaces.
• This approach can be useful for
targeting drugs to tumor tissues
or even normal cells.

57. Chitosan as a Novel Nasal Delivery System
 A nasal solution formulation of the cationic material chitosan was
shown to greatly enhance the absorption of insulin across the nasal
mucosa of rat and sheep.
 The absorption promoting effect was concentration dependent with
the optimal efficacy obtained for concentrations higher than 0.2% and
0.5% in rats and sheep, respectively.
 The absorption promoting effect was reversible with time in a “pulse-
chase” study. Histological examination of the nasal mucosa of rats
exposed to a chitosan solution for 60 minutes showed little change

61. Novel Nasal Devices for the Efficient Drug
Delivery:
 Now a day, nasal drug delivery has occupied an important place in
the field of drug delivery technology.
 A range of medicaments can be successfully delivered at the site of
action using drug delivery devices.
 A successful nasal drug delivery device seems to deliver
medication efficiently, necessarily non-invasive, helps in rapid
onset of action, patient friendly for self administration and should
exhibit minimal side effects.
 Since constructing an efficient drug delivery device, capable of
achieving sufficient local, systemic or brain distribution of drug is
a challenge, usually requires a robust and innovative technology.

62. NASAL DRUG DELIVERY DEVICES
 Opti-nose is a noval drug delivery decive which is used in reliable
and efficient drug delivery via nasal route.
 The breath powered delivery concept was developed to overcome the
anatomical and physiological characteristics of the nasal airways that
limit the delivery efficiency of traditional delivery technologies.
 The OptiNose devices are designed to be the first and only devices
which truly sum up all the unique characteristics of the nasal cavity to
effectively deliver drugs more consistently and reliably to all regions of
the nasal cavity.
 This device is now in increasing demand due to its broad spectrum use
in systemic, local, nose to brain and vaccine delivery.

64. VIA NASE
ViaNase TM with Controlled Particle Dispersion (CPD) ™ technology
allows formulations to negotiate the complicated structure and
varied airflows of the nasal cavity. The major precedence of
ViaNase TM includes consistent dosing, having superior efficacy,
preservative- free unit dose ampoules, patient friendly operations,
pocket sized portability.
CPDTM, developed by Kurve Technology Inc. USA, provides the
opportunity to change drug delivery as it is known today, creating a
paradigm shift in the industries for treating various sorts of
diseases and ailments.

66. DIRECT HALER TECHNOLOGY
 The innovation takes advantage of the patient's anatomy to improve nasal
delivery effectiveness and convenience. The integrated nasal device and delivery
method enables nasal delivery of very fine particles, without the risk of
pulmonary deposition.
 The Direct-Haler TM Nasal device has successfully been used in clinical trials, and
has confirmed patient acceptability. The single-use, disposable device, as shown
in figure 7, is for both mono and bi- dose delivery, in a pre-metered, prefilled
dose format.
 The device offers effective, accurate, repeatable and hygienic dosing, and is
intuitively easy to use.
 When air is being blown out of the mouth against a resistance, the airway
passage between the oral and nasal cavities automatically closes. This
anatomical feature is activated when the patient uses DirectHaler TM Nasal device
for blowing their nasal dry-powder dose into their nostril.

69. There is no question that the nasal route has a great potential
for systemic drug delivery. As nose- to- brain delivery makes it
possible to by-pass the blood-brain barrier for certain drugs;
administration of drugs via this route for treatment of
neurological diseases presents exciting opportunities. Several
strategies have been developed to enable the drug molecules to
attach onto the mucus or epithelial layer, thus preventing them
from being cleared from the nasal cavity. The application of
lectins, thiomers, alginate poly-ethylene glycol
acrylate,poloxamers, VITANASE, OTINOSE, direct haler technology
have been of great use to overcome the challenges.

70.  Singh S, Kanupriya and kumar S.L.H, INTRANASAL
THERMOREVERSIBLE MUCOADHESIVE GELS: A Review,
International Journal of Pharmacy, 2012; vol:2, Issue-3.
Utkarshini Anand, Tiam Feridooni and Remigius U. Agu, Novel
Mucoadhesive Polymers for Nasal Drug Delivery,INTECH.
(http://dx.doi.org/10.5772/52560)
 Alagusundaram M*, Chengaiah B, Gnanaprakash K, Ramkanth S,
Chetty CM, Dhachinamoorthi D, Nasal drug delivery system - An
overview, International Journal of Research in Pharmaceutical
Sciences, 2010 Vol-1, Issue-4, 454-465.
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