Abstract: A method for producing chitosan from naturally occurring chitin-containing raw material, such as crustacean shells, includes an optional pretreatment step to remove non-chitin rich organic material for example, shrimp flesh, from the raw material, e.g., shrimp shells. The optional pre-treatment is followed by a demineralization step utilizing a mild hydrochloric acid solution and a deproteination step utilizing a mild sodium hydroxide solution. The deproteination step is followed by a deacetylation step to remove the acetyl group from N-acetylglucosamine (chitin) to form an amine group, yielding d-glucosamine (chitosan). Each step is followed by a washing step and the product is dried, preferably at a temperature not in excess of about 65° C. Known purification and grinding steps may also be used to produce the final chitosan product. The process is carried out in equipment comprising a series of substantially identical or similar tanks (18, 26, 36, etc.) and dryers (62, 62?), suitably interconnected.

Abstract: Modified chitosan hemostatic agents include reverse micelles (10) having an outer hydrophobic shell (12) of suitable biocompatible hydrophobic components such as alkanes, and hydrophilic positively charged chitosan moieties (14) enclosed within the hydrophobic shell (12). The hydrophobic shell (12) may be formed by attaching hydrophobic moieties to one end of chitosan polymer molecules while retaining sufficient reactive (positively charged) amine groups on the remainder of the chitosan polymers for effective blood clotting. The resulting reverse micelles (10) have the capability of penetrating mucous membranes such as nasal mucosa (20) or otherwise penetrating to bleed sites shielded or partially shielded by mucosa or other tissues.

Abstract: Glass surfaces, for example, windshield surfaces, have a durable hydrophobic coating applied thereto. The glass surface is first treated by any suitable method to enhance the ability of a chitosan polymer coating to durably or substantially permanently adhere thereto. Once the chitosan coating has been applied to the glass surface, the normally hydrophilic chitosan coating is rendered hydrophobic by suitable treatment, for example, by a combination of enzymatic and chemical treatments. Alternatively, the chitosan may be rendered hydrophobic prior to coating it on the glass surface, but that is a less preferred technique. The method of the invention provides a glass article having a hydrophobic surface.

Abstract: A method for producing chitosan from naturally occurring chitin-containing raw material, such as crustacean shells, includes an optional pretreatment step to remove non-chitin rich organic material for example, shrimp flesh, from the raw material, e.g., shrimp shells. The optional pretreatment is followed by a demineralization step utilizing a mild hydrochloric acid solution and a deproteination step utilizing a mild sodium hydroxide solution. The deproteination step is followed by a deacetylation step to remove the acetyl group from N-acetylglucosamine (chitin) to form an amine group, yielding d-glucosamine (chitosan). Each step is followed by a washing step and the product is dried, preferably at a temperature not in excess of about 65° C. Known purification and grinding steps may also be used to produce the final chitosan product. The process is carried out in equipment comprising a series of substantially identical or similar tanks (18, 26, 36, etc.) and dryers (62, 62?), suitably interconnected.

Abstract: A method for producing chitosan from naturally occurring chitin-containing raw material, such as crustacean shells, includes an optional pretreatment step to remove non-chitin rich organic material for example, shrimp flesh, from the raw material, e.g., shrimp shells. The optional pretreatment is followed by a demineralization step utilizing a mild hydrochloric acid solution and a deproteination step utilizing a mild sodium hydroxide solution. The deproteination step is followed by a deacetylation step to remove the acetyl group from N-acetylglucosamine (chitin) to form an amine group, yielding d-glucosamine (chitosan). Each step is followed by a washing step and the product is dried, preferably at a temperature not in excess of about 65° C. Known purification and grinding steps may also be used to produce the final chitosan product. The process is carried out in equipment comprising a series of substantially identical or similar tanks (18, 26, 36, etc.) and dryers (62, 62?), suitably interconnected.

Abstract: Glass surfaces, for example, windshield surfaces, have a durable hydrophobic coating applied thereto. The glass surface is first treated by any suitable method to enhance the ability of a chitosan polymer coating to durably or substantially permanently adhere thereto. Once the chitosan coating has been applied to the glass surface, the normally hydrophilic chitosan coating is rendered hydrophobic by suitable treatment, for example, by a combination of enzymatic and chemical treatments. Alternatively, the chitosan may be rendered hydrophobic prior to coating it on the glass surface, but that is a less preferred technique. The method of the invention provides a glass article having a hydrophobic surface.