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...

The effects of replacing PCL with acrylic acid grafted PCL (PCL-g-AA) on the structure and properties of a PCL/chitosan composite were investigated. The properties of both PCL-g-AA/chitosan and PCL/chitosan were examined and compared using FTIR, H and C nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), and a biodegradation test. With PCL-g-AA in the composite, compatibi...

Aim This study aimed to compare, through dentin microhardness and colorimetric analysis, the chelating effect of 0.2% chitosan solubilized in different acids. Materials and Methods The second and third cuts of the cervical region of maxillary central incisors were divided into four quadrants, resulting in eight specimens, which were treated with 50 μL of solution for 5 min according to their ...

introduction: chitosan possesses more than 5000 glucossamine residue. since chitosan possesses potentially reactive amino functional groups, this polymer has been shown to be of potential use in many different fields, including as an antifungal compound in agriculture, flocculating in waste water treatment, a food additive and alimentary industries, hydrating agent in cosmetics and more recentl...

Osteoblasts play critical roles in bone formation. Our previous study showed that chitosan nanofibers can stimulate osteoblast proliferation and maturation. This translational study used an animal model of bone defects to evaluate the effects of chitosan nanofiber scaffolds on bone healing and the possible mechanisms. In this study, we produced uniform chitosan nanofibers with fiber diameters o...

Mucoadhesive gelling systems based on chitosan and chitosan/β-glycerophosphate (β-GP) were developed in order to increase clotrimazole residence time in the vaginal cavity. Ex vivo mucoadhesiveness using porcine vaginal mucosa followed with mechanical, viscoelastic, and swelling properties of prepared hydrogels were evaluated. Drug-free, sterile, unmodified, and β-GP crosslinked chitosan were i...

The Schiff bases of chitosan were synthesized by the reaction of chitosan with 3-(4-substituted-phenyl)-1-phenyl-1H-pyrazole-4-carbaldehyde. The structure of the prepared chitosan derivatives was characterized by FT-IR spectroscopy, elemental analysis, and X-ray diffraction studies and thermogravimetric analysis (TG). The results show that the specific properties of Schiff bases of chitosan can...