Response surface methodology (RSM) was used for controlling molecular weight (MW) and degree of deacetylation (DOD) of chitosan in chemical processing. In a reduced model, MW of chitosan is y = 1736166.406 - 250.745X(1)X(2) - 265.452X(2)X(3), with R( 2) = 0.86, and DOD of chitosan is y = 30.6069 + 0.3396X(1) + 0.4948X(2) + 0.0094X(3)(2), with R( 2) = 0.89. MW of chitosan depends on the crosspro...

Thailand is one of the major producers and exporters of shrimp and other marine products worldwide. Over 600,000 metric tons of marine products containing chitinous materials, shrimp, crab and squid, are produced yearly, which resulted in abundant amount of raw materials for the production of chitin-chitosan. Chitin-chitosan industry in Thailand has grown considerably in the past decade. Howeve...

Chitosan, a copolymer of glucosamine and N-acetyl glucosamine, is a polycationic, biocompatible and biodegradable polymer. In addition, chitosan has different functional groups that can be modified with a wide array of ligands. Because of its unique physicochemical properties, chitosan has great potential in a range of biomedical applications, including tissue engineering, non-viral gene delive...

Nanoparticles of approximately 10nm in diameter made with chitosan or lactic acid-grafted chitosan were developed for high drug loading and prolonged drug release. A drug encapsulation efficiency of 92% and a release rate of 28% from chitosan nanoparticles over a 4-week period were demonstrated with bovine serum protein. To further increase drug encapsulation, prolong drug release, and increase...

Due to the existence of new methodologies that have reduced the production costs of microbiological chitosan, this paper puts forward the use of agro-industrial residues in order to produce microbiological chitosan and to apply chitosan as an innovative resource for removing acid orange 7 (AO7) from wastewaters. The best culture conditions were selected by a full 24 factorial design, and the re...

The purpose of the present study was to investigate whether the use of a chitosan mouthrinse could be efficacious in reducing plaque and saliva mutans streptococci level. A randomized crossover clinical trial was performed to evaluate the effect of a rinse with 0.5% chitosan for 14 days on plaque formation and mutans streptococci counts in saliva. Twenty-four subjects were randomly assigned eit...

The aim of this study was to synthesis the conjugated chitosan by covalent attachment of thiol moieties to the cationic polymer, mediated by a carbodiimide to improve permeation properties of chitosan. Thioglycolic acid was covalently attached to chitosan by the formation of amide bonds between the primary amino groups of the polymer and the carboxylic acid groups of thioglycolic acid. Hence, t...

Tyrosinase was used to initiate the grafting of peptides onto the amine-containing polysaccharide chitosan. Chemical evidence for covalent grafting was obtained from electrospray mass spectrometry for products formed from reactions with glucosamine (the monomeric unit of chitosan) and the model dipeptide Tyr-Ala. When this model dipeptide was incubated with tyrosinase and chitosan, there was a ...

Consecutive expression of the high‑risk human papillomavirus (HPV) oncoproteins, E6 and E7, is pivotal for malignant transformation and maintenance of the malignant phenotype. These oncogenes may be potential targets of gene silencing‑based molecular therapies for human cervical cancer. The aim of the present study was to evaluate the efficacy of ...

Chitosan and nanoparticle silver are both materials with demonstrated antimicrobial properties and have been proposed singly or in combination as constituents of antimicrobial burn dressings. Here, we show that they combine synergistically to inhibit the in vitro growth of Gram-positive methicillin-resistant Staphylococcus aureus (MRSA) and Gram-negative bacteria (Pseudomonas aeruginosa, Proteu...