2. Introduction
Chitosan is a linear polysaccharide composed of randomly distributed α-(1→4)-
linked D-glucosamine ( deacetylated unit) and N-acetyl-D-glucosamine (acetylated
unit).
It is made by treating the chitin shells of shrimp and other crustaceans.
3. Chitin: a brief history
1811 Chitin was first discovered by Professor Henri Braconnot,
who isolated it from mushrooms and name it “Fungine”.
1823 Antoine Odier found chitin while studying beetle cuticles and
named “chitin” after Greek word “chiton” (tunic, envelope).
1859 Rought discovered chitosan, a derivative of chitin.
1920s Production of chitin fibers from different solvent systems.
1930s Exploration of synthetic fibers.
1950s The structure of chitin and chitosan was identified by X-ray
diffraction, infrared spectra, and enzymatic analysis.
1970s “Re-discovery” of the interest in chitin and chitosan.
1977 1st international conference on chitin/chitosan.
Henri Braconnot (1780-1856)
4. What is Chitin?
• Chitin is a natural polysaccharide.
• Structure similar to cellulose with hydroxyl group replaced by acetamino group.
• N-acetyl-glucosamine units in β-(1→4) linkage.
• Found in the exoskeleton as well as in the internal structure of shells of shrimp
and crustaceans.
• Chitin has 3 polymorphic form:
α-chitin, β-chitin, γ-chitin
α-chitin:
- the most abundant form
- anti-parallel configuration
- highly ordered crystalline
- strong H-bonding (N-
H····O=C)
- rigid, intractable, insouble.
β-chitin:
- found in diatom
spines and squid pens
- parallel configuration
- weak H-bonding
- unstable, soluble in
water.
γ-chitin:
- mixture of α and β-
chitin
- intermediate
properties.
6. 6
Deacetylation
(boiling 40-50%
NaOH)
Preparation of Chitosan
• Produced commercially by deacetylation of chitin.
• The degree of deacetylation (%DD) can be determined by NMR spectroscopy.
• the %DD in commercial chitosan ranges from 60 to 100%.
7. Properties of Chitosan-
• Unique characteristics of chitin and chitosan:
Biocompatible
Biodegradable
Non-toxic
Remarkable affinity to proteins
Ability to be functionalized
Renewable
Abundant
• Antimicrobial properties:
Mechanism still unknown hypotheses:-
binding to cell-wall phospholipids of
Gram-negative bacteria
modification of cell-wall permeability and
loss of material
inhibition of certain enzymes.
8. Determination of degree of deacetylation(DD%):
• Measured by the acid-base titration method (Domard & Rinaudo
1983) with modifications.
• Chitosan (0.1 g) was dissolved in 30 ml HCl aqueous solution
(0.1mol/l) at room temperature.
• Add 5–6 drops of methyl orange.
• The red chitosan solution was titrated with 0.1mol/l NaOH
solution until it turned orange.
The DD% was calculated by the formula:
C1 = concentration of standard HCl (mol/l),
C2 = standard NaOH solution (mol/l),
V1= volume of the standard HCl aqueous solution used to
dissolve chitosan (ml),
V2= volume of standard NaOH solution consumed during
titration (ml),
M= weight of chitosan (g)
9. Water binding capacity-
• Measured using a modified method of Knorr.
• It carried out by weighing a centrifuge tube containing 0.5 g of sample, adding 10 ml of
water and mix it on a vortex mixer for 1 min.
• Contents were left at ambient temperature (29°C) for 30 min. After the supernatant was
decanted, the tube was weighed again.
WBC was calculated as follows:
10. Fat binding capacity-
• It also measured by using a modified method of Knorr.
• Carried out by weighing a centrifuge tube containing 0.5 g of sample, adding 10 ml
of oil (soybean oil) and mixing on a vortex mixer for 1 min.
• The contents were left at ambient temperature for 30 min. After the supernatant was
decanted, the tube was weighed again.
FBC was calculated as follows:
Viscosity-
• The viscosity of chitosan increases with increasing chitosan concentration,
decreasing temperature, and increasing degree of deacetylation.
Reference- J. Bangladesh Agril. Univ. 12(1): 153–160, 2014 ISSN 1810-3030
Production and characterization of chitosan from shrimp waste
M. S. Hossain* and A. Iqbal
Department of Food Technology & Rural Industries, Bangladesh Agricultural University,
Mymensingh-2202,
Bangladesh, *Email: sajjad.bau@gmail.com
11. Moisture content-
• It absorbs moisture from atmosphere.
• Particle size distribution: <30 mm
• determined by the gravimetric method
Solubility-
• Sparingly soluble in water.
• Practically insoluble in ethanol and other organic solvents.
• Solubility is affected by degree of deacetylation.
PH: 4.0-6.0
Density: 1.35-1.40 g/cm3
Glass transition temperature: 203°C
13. Derivatives of Chitosan-
Reference- MARCIN H. STRUSZCZYK, Tricomed SA, ul' Piotrkowska 27 0, 90-950 Łódź
e-mail: martinst@skrzynka.pl Chitin and Chitosan
19. Applications and Uses-
APPLICATION EXAMPLE
Water treatment Removal of metal ions
Flocculant/coagulant
(proteins, dyes, amino
acids)
Filtration
Pulp and paper Surface treatment
Photographic paper
Carbonless copy paper
Biomedical Bandages, sponges
Artificial blood vessels
Blood cholesterol control
Tumor inhibition
Skin burns, artificial skin
Eye humor fluid
Contact lenses
Controlled release of drugs
20. APPLICATION EXAMPLE
Cosmetics Make-up powder
Nail polish
Moisturizers
Biotechnology Enzyme/cell
immobilization
Protein separation
Chromatography
Glucose electrode
Agriculture Seed/leaf coating
Hydroponic/fertilizer
Controlled agrochemicals
release
21. Biomedical Applications
• Wound dressings are used to protect
wound skin form insult, contamination
and infection
• Chitin-based wound dressings
- Increase dermal regeneration
- Accelerate wound healing
- Prevent bacteria infiltration
- Avoid water loss
• Chitin surgical threads - strong, flexible,
decompose after the heals
Chitosan wound dressings
1. Wound Dressing 2. Anticoagulation
Anticoagulation is essential for open-
heart surgery and kidney dialysis
Preventing blood from clotting during
the surgery
Sulfated chitosan derivatives have
good anticoagulant activity
22. • Tissue engineering research is
based on the seeding of cells onto
porous biodegradable matrix
• Chitosan can be prepared in porous
forms permitting cell growth into
complete tissue
3. Tissue Engineering 4. Orthopedic Applications
Bone is a composite of soft collagen
and hard hydroxyapatite (HA)
Chitin-based materials are suitable
candidate for collagen replacement
(chitin-HA composite)
Mechanically flexible, enhanced bone
formation
Temporary artificial ligaments for the
knee joint
Porous character of chitosan scaffold
50μm
23. 5. Drug Delivery
Hydrogels
• Hydrogels are highly swollen, hydrophilic polymer
networks that can absorb large amounts of water
• pH-sensitive hydrogels have potential use in site-
specific drug delivery to gastrointestinal tract (GI)
• Chitosan hydrogels are promising in drug delivery
system
Microcapsules
• Microcapsule is defined as a spherical
empty particle with size varying from
50 nm to 2 mm
• Chitosan-based microcapsules are
suitable for controlled drug release.
24. Biotechnology applications
Gene Delivery
• Viral gene delivery / Non-Viral gene delivery
• Viral: high transfection efficiency, dangerous
• Non-Viral: low transfection efficiency, safer
• Chitosan-DNA complexes can be optimized to
enhance the transfection efficiency
Enzyme immobilization
Specific, efficient, operate at mild conditions
Unstable, sensitive after isolation and purification
Chitin and chitosan-based materials are suitable
enzyme immobilizers
- Biocompatible
- Biodegradable
- High affinity to protein
- Reactive functional group
25. Reference of Applications and uses- Journal of Scientific & Industrial Research Vol.
63, January 2004, pp 20-31 Chitin and chitosan: Chemistry, properties and
applications Pradip Kumar Dutta*, Joydeep Dutta+ and V S Tripathi+ Department of
Chemistry, Motilal Nehru National Institute of Technology, Allahabad 211 004
26. ACKNOWLEDGEMENT
I wish to express my sincere gratitude to Dr. Jyoti
Pandey for providing me an opportunity to do my
presentation work on “Chitosan”
I sincerely thank Dr. Jyoti Pandey for their guidance and
encouragement in carrying out this presentation work. I
also wish to express my gratitude to my class friends of
BBAU, who rendered their help during the period of my
presentation work.