Chitosan Nanofiber

G. M. AhshanuzzamanStudent Id : 1105154th Year 1st TermForestry and Wood Technology DisciplineKhulna UniversityKhulna

Chitin

Chitin (C8H13O5N)n is a polysaccharide found in the outer

skeleton of insects, crabs, shrimps, and lobsters and in the internal

structures of other invertebrates. Chitin is composed of ß(1-4)

linked units of the amino sugar N-acetyl-glucosamine

ChitosanChitosan is a linear polysaccharide composed of randomly distributed β-(1-4)-linked D-

glucosamine (deacetylated unit) and N-acetyl-D-glucosamine (acetylated unit). It is made

by treating shrimp and other crustacean shells with the alkali sodium hydroxide. It is a

linear polysaccharide derived from the Ndeacetylation of chitin, which is the second most

abundant polysaccharide

Nanofibers are defined as particulate dispersions or solid particles with a size in the range of 1–1000 nm.

Sources of Chitin and Chitosan • Insects

o Cuticle o Ovipositors o Beetle cocoon • Crustaceans

o Crab shell o Shrimp shell

• Squid o Ommastrephes pen o Loligo stomach wall

• Centric Diatoms o Thalassiosira fluviatilis o Algae

• Fungi o Mucor rouxi o Aspergillis nidulans

Preparation of Chitin and ChitosanCrab or Shrimp Shell

↓ Mill ↓

Decolorize solvent extraction

↓ Demineralize

↓ Wash

↓ De proteinize

20% NaOH ↓

Purified Chitin ↓

Deactylate ↓

Purified Chitosan

Preparation of Chitosan Nanofiber

A colloidal suspension of ca. 1 wt. % chitin nanofiber and chitosan solution in about 4 % acetic acid was mixed under magnetic stirring for 12 hrs to allow uniform dispersion.

Casting was done on a round glass mold of Ø = 72 cm covered with a Teflon film surface. Drying was performed in an oven at 37 °C.

Evaporation of water and acetic acid resulted into a consolidated nanostructured composite film.

Preparation of Chitosan Nanofiber Composites

Light and strong

Ultra-fine fibers (fiber width: about 3 nm)

Large specific surface area

Low thermal expansion

High gas barrier properties

The modulus of elasticity has the same level of strength as that of aramid fiber, which is

known as a high-strength fiber,

Thermal expansion on par with glass.

Its tensile strength is about 500MPa

Its stiffness is about 140–220 Gpa

Films made from nanocellulose have high strength (over 200 MPa),

High stiffness (around 20 GPa) and high strain

Its strength/weight ratio is 8 times that of stainless steel.

Properties of Chitosan Nanocomposite

Agricultural Applications Wastewater Treatment Applications Food Industry Applications Medical Applications Artificial skin Surgical sutures Artificial blood vessels Surgical Adhesion Used for preservative purposes while

packaging foods and in dentistry to eliminate caries.

Anti-viral Dental plaque inhibition Bone healing treatment Anti bacterial Orthopedic and

Periodontal Applications Tissue Engineering Wound Healing Drug Delivery

Applications of Chitosan Nanocomposite

Cars Transparent Cell-Phone Transparent LED-TV Transparent Watch Transparent Valuable

Ornaments Transparent panel Products Transparent hard-wares for

Computer

Future Inventions from Chitosan Nanocomposite