Chitin

Catalog	ACM1398614-10
CAS	1398-61-4
Structure
Description	The monomers are identified as N-Acetyl-Amnioglucose. Chitin is a polysaccharide containing nitrogen in which monomers occur with the glycosidically linked components beta 1,4. It is the same coupling as glucose with cellulose, however in chitin the hydroxyl group of the monomer is replaced with an acetyl amine group. The resulting, stronger hydrogen bond between the bordering polymers makes chitin harder and more stabile than cellulose.
Synonyms	(1,4)-N-acetyl-D-glucos-2-amine
IUPAC Name	N-[(2R)-2,4,5-trihydroxy-6-(hydroxymethyl)oxan-3-yl]acetamide
Molecular Weight	161.16
Molecular Formula	(C8H13NO5)n
Canonical SMILES	CC(=O)NC1[C@@H](OC(C(C1O)O)CO)O
InChI	OVRNDRQMDRJTHS-WTZNIHQSSA-N
InChI Key	InChI=1S/C8H15NO6/c1-3(11)9-5-7(13)6(12)4(2-10)15-8(5)14/h4-8,10,12-14H,2H2,1H3,(H,9,11)/t4?,5?,6?,7?,8-/m1/s1
Boiling Point	737.18 °C
Melting Point	>300 °C(dec.)
Flash Point	269.8°C
Purity	96%
Density	1.37g/ml
Solubility	Insoluble in water, organic solvents, weak acids and lyes Soluble in concentrated formic acid and methane sulfonic acid, Strong acids split chitin into acetic acid and D-amino glucose (monomer of chitin), strong lyes split chitin into Acetic acid and chitosan.
Appearance	White to beige solid
Assay	0.98
Grade	PXPC
Packaging	1 ton
Stability	Stable. Incompatible with strong oxidizing agents.

Case Study

Preparation of Chitosan Nanofiber/Methacrylic Resin Composites

Shinsuke Ifuku, et al. Green Chem., 2011,13, 1708-1711.

The nanocomposites are optically transparent due to the nano-size effect. This finding is applicable to chitosan nanofibers to obtain optically transparent nanocomposites with acrylic resins. In this work, chitosan nanofiber composites were prepared with 11 (meth)acrylic resins and characterized for transparency, Young's modulus, mechanical strength, and thermal expansion. The results show that the composites are highly transparent and flexible, and have low thermal expansion, high Young's modulus, and high tensile strength.
Fabrication of chitin nanofiber composites
· Chitosan nanofibers were prepared from commercially available crab shell chitosan powder. The fibrillated chitosan nanofibers were dispersed in water at a fiber content of 0.1 wt% to form a suspension. The suspension was filtered and hot pressed at 100 ◦C for 30 min to obtain dried flakes.
· The chitosan nanofiber sheets were cut into 3 cm × 4 cm flakes with a thickness of about 45 mm and a weight of 40 mg. The thin sheets were impregnated with bifunctional (meth) acrylic resins (including DCP, A-600, BPE and A-BPE) and 2 wt% 2-hydroxy-2-methylpropiophenone photoinitiator under reduced pressure for 24 h.
· The resin-impregnated thin sheets were polymerized at 40 mW cm-1 for 8 min using a UV curing device. The resulting chitin nanofiber composite membrane was about 60 mm thick and had a fiber content of about 40%.

Preventive Effect of Chitin Nanofibers in an Acute Ulcerative Colitis Model

Azuma, Kazuo, et al. Carbohydrate Polymers, 2012, 87(2), 1399-1403.

The study examined the preventive impact of chitin nanofibers on a mouse model of acute ulcerative colitis induced by dextran sodium sulfate (DSS). The findings indicated that chitin nanofibers alleviated clinical symptoms and suppressed ulcerative colitis. Furthermore, they decreased myeloperoxidase activation in the colon and lowered serum levels of interleukin-6. In contrast, chitin powder did not demonstrate any inhibitory effects on DSS-induced acute ulcerative colitis.
Experimental design
· A total of 68 mice were randomly assigned to six groups: a control (+) group receiving only dextran sulfate sodium (DSS, n=17), a control (-) group receiving tap water (n=5), a (+) group receiving chitin nanofibrils and DSS (n=17), a (-) group receiving only chitin nanofibrils (n=7), a (+) group receiving chitin powder suspension (chitin-PS) and DSS (n=16), and a (-) group receiving only chitin-PS (n=6).
· To induce colitis, mice in all groups were given 3% DSS ad libitum for 6 days. Prior to DSS administration, mice in the chitin nanofibril and chitin-PS groups were given 0.1% of their respective compounds dissolved in tap water ad libitum for 7 days. Blood samples and colon tissue were collected on days 3 and 5 in the control (+), chitin nanofibril (+), and chitin-PS groups (n=5 each) and on day 6 in all groups (n=5-7).