I am looking for methods to make N,O-carboxymethyl chitosan. I have
found one in an expired US patent and another in a 20 year old journal
article. Just wondering if anyone knows of more recent published
methods or could forward a copy. Thanks!
Do any patents reference the expired one?
QUOTE (Mark Thorson+May 15 2004, 04:58 PM)
Do any patents reference the expired one?
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: 
Dear Sir:
I am Arick Quan.
Shanghai Shengyao Bio-Tech Co.,Ltd offer the high-quality and competitive price Carboxymethyl Chitosan, Chitosan Oligosaccharide, Chitosan, 1,2,3,4,6-Pent-O-Acetyl-D-Glucose, 2,3,4,6-Tetra-acetyl-α-D-Bromoglucose.
Welcome to our website and have a look: http://www.shengyaobio.com
Best regards!
Arick (shyarick@hotmail.com)
:
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Shanghai Shengyao Bio-Tech Co.,Ltd
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Carboxymethyl Chitosan
The product appearance is white. The viscosity ranage is base on the customers` need(1%, 2% concentration)
TECHNOLOGY INDEX:
1. NAME: Carboxymethyl chitosan
2. APPEARANCE: Off-white ,White,
3. ODOUR: Odourless
4. SOLUBILITY PROPERTY: Solution completely
5. SOLUTION APPEARANCE : Transparent
6. WATER CONTENT: ≤10%
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Hello! High-quality Carboxymethyl ChitosanShanghai Shengyao Bio-Tech Co.,Ltd
E-mail: shenyaosw7@yahoo.com.cnhttp://www.shengyaobio.com
Carboxymethyl Chitosan
The product appearance is white. The viscosity ranage is base on the customers` need(1%, 2% concentration)
TECHNOLOGY INDEX:
1. NAME: Carboxymethyl chitosan
2. APPEARANCE: Off-white ,White,
3. ODOUR: Odourless
4. SOLUBILITY PROPERTY: Solution completely
5. SOLUTION APPEARANCE : Transparent
6. WATER CONTENT: ≤10%
7. PH: 7-9
8. VISCOSITY: Base on the customers` need
9. DAC: ≥85%,≥90%,≥95%
10. HEAVY METALS: ≤10ppm
11. As CONTENT: ≤1.0ppm
Hi, i'm also trying to a find a method for producing carboxymethyl chitosan. There is a more recent method that i've come across (non-specific N,O carboxylation):
Chitosan (10 g) was suspended in 50 wt% NaOH and
kept at -20 C for 16 h. The frozen alkali chitosan was
transferred to 2-propanol (100 mL), and chloroacetic acid
(10 g) was added in portions. After stirring at room temperature
for 2 h, heat was applied to bring the reaction
mixture to a temperature of 60 C for another 2 h. After
dialyzing against deionized water for 3 days, the product
was vacuum dried at room temperature.
It's from a journal by Fan et al. Preparation and properties of alginate/carboxymethyl chitosan blend fibers. [I]Carbohydrate Polymers, 65(2006) 447-452
I hope this helps!
India Sweeney
Chitosan (10 g) was suspended in 50 wt% NaOH and
kept at -20 C for 16 h. The frozen alkali chitosan was
transferred to 2-propanol (100 mL), and chloroacetic acid
(10 g) was added in portions. After stirring at room temperature
for 2 h, heat was applied to bring the reaction
mixture to a temperature of 60 C for another 2 h. After
dialyzing against deionized water for 3 days, the product
was vacuum dried at room temperature.
It's from a journal by Fan et al. Preparation and properties of alginate/carboxymethyl chitosan blend fibers. [I]Carbohydrate Polymers, 65(2006) 447-452
I hope this helps!
India Sweeney
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