Advances of chitosan and its derivatives in the prevention and treatment of oral diseases / 生物工程学报

Chitosan is a natural polysaccharide that is widely used in food, textile, cosmetics, and medical industries. In the field of stomatology, chitosan and its derivatives are widely used in the treatment of many common oral diseases due to a variety of excellent biological properties, such as anti-infection, drug-loading, remineralization and osteogenesis. This review summarized the latest advances in the biological properties of chitosan and its derivatives, as well as their applications in the prevention and treatment of oral diseases.

The influence of the gut microbiota on the bioavailability of oral drugs

Due to its safety, convenience, low cost and good compliance, oral administration attracts lots of attention. However, the efficacy of many oral drugs is limited to their unsatisfactory bioavailability in the gastrointestinal tract. One of the critical and most overlooked factors is the symbiotic gut microbiota that can modulate the bioavailability of oral drugs by participating in the biotransformation of oral drugs, influencing the drug transport process and altering some gastrointestinal properties. In this review, we summarized the existing research investigating the possible relationship between the gut microbiota and the bioavailability of oral drugs, which may provide great ideas and useful instructions for the design of novel drug delivery systems or the achievement of personalized medicine.

Pharmacokinetics and tissue distribution of mitomycin amphiphilic chitosan polymeric micelles in rats / 中国药学杂志

OBJECTIVE: To investigate the pharmacokinetics and tissue distribution of mitomycin amphiphilic chitosan polymeric micelles (MMC-ACPM) in rats. METHODS: Mitomycin injection (MMC-INJ) and MMC-ACPM were administered to rats through tail vein at the dosage of 0. 5 mg · kg-1. An ultra-fast liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) method was established to determine the concentration of mitomycin (MMC) in plasma and tissues of rats. RESULTS: The t1/2(β) of MMC-INJ and MMC-ACPM in plasma were estimated to be (0.67 ± 0.36) and (3.33 ± 1.47) h, respectively. The AUC0→∞ were calculated to be (120.94 ± 13.77) and (140.95 ± 11.56) ng · mL-1 · h-1, respectively. The MRT were (0.83 ±0.13) and (1.56 ± 0.22) h, and CL were (0.005 ± 0.001) and (0.003 ± 0.001) L · h-1 · kg-1, respectively. Compared with MMC-INJ group, MMC-ACPM group had lower concentrations of MMC in heart, liver, spleen, lung, and kidney of rats. CONCLUSION: MMC-ACPM can prolong the circulation of MMC in vivo, improve its bioavailability, and reduce the accumulation in liver and kidney, which can improve curative effects and reduce toxicity.

Synthesis of a new chitosan derivative and assay of Escherichia coli adsorption / 药物分析学报

A new chitosan derivative is prepared using chitosan.Ethyl chlorocarbonate was first introduced to the hydroxyl group of phthaloylchitosan through a nucleophilic reaction.Hydrazine was then added to recover the amino groups of chitosan and promote cross-linking.The structure of this new chitosan derivative was characterized by Fourier transform infrared (FT-IR) and proton nuclear magnetic resonance (1H NMR) spectroscopy,and its physical properties were determined by X-ray diffraction (XRD),differential scanning calorimetry (DSC),and thermogravimetric analysis (TGA).The thermal and chemical stabilities of the new derivative were improved compared with those of native chitosan.Assay of Escherichia coli adhesion on a film based on this chitosan derivative showed good adsorption and biofilm formation.

Synthesis of a new chitosan derivative and assay of Escherichia coli adsorption / 药物分析学报

A new chitosan derivative is prepared using chitosan.Ethyl chlorocarbonate was first introduced to the hydroxyl group of phthaloylchitosan through a nucleophilic reaction.Hydrazine was then added to recover the amino groups of chitosan and promote cross-linking.The structure of this new chitosan derivative was characterized by Fourier transform infrared（FT-IR）and proton nuclear magnetic resonance（1H NMR）spectroscopy,and its physical properties were determined by X-ray diffraction（XRD）,differential scanning calorimetry（DSC）,and thermogravimetric analysis（TGA）.The thermal and chemical stabilities of the new derivative were improved compared with those of native chitosan.Assay of Escherichia coli adhesion on a film based on this chitosan derivative showed good adsorption and biofilm formation.