[In vitro study of electrospun polycaprolactone/chitosan nano fiber membrane guided bone regeneration].

PURPOSE: To explore the effect of electrospining chitosan/polycaprolactone nano fiber membrane on regeneration of bone defects in vitro. METHODS: Chitosan/polycaprolactone nanofiber membrane was prepared by electrospinning technique. According to alkaline phosphatase activity and Western blot results, the ability of osteogenic differentiation of cells by fiber membrane as carrier was evaluated. The data was analyzed statistically with SPSS17.0 software package. RESULTS: The osteogenic differentiation capacity of electrospining chitosan/polycaprolactone nano fiber membrane was significantly higher than the control (without materials), and the difference was significant (P<0.05). CONCLUSIONS: Electrospinning chitosan/polycaprolactone nano fiber membrane can promote osteogenic differentiation of cells in vitro, which provides a scientific basis for clinical regeneration of bone defects.

[Rapid identification of micro-constituents in monoammonium glycyrrhizinate raw materials by high-pressure solid phase extraction-high performance liquid chromatography-mass spectrometry].

OBJECTIVE: To establish a method for rapid identification of micro-constituents in monoammonium glycyrrhizinate by high-pressure solid phase extraction-high performance liquid chromatography-mass spectrometry. METHOD: HPLC preparative chromatograph was adopted for determining the optimal method for high-pressure solid phase extraction under optimal conditions. 5C18-MS-II column (20.0 mm x 20.0 mm) was used as the extraction column, with 35% acetonitrile-acetic acid solution (pH 2. 20) as eluent at the speed of 16 mL x min(-1). The sample size was 0.5 mL, and the extraction cycle was 4.5 min. Then, extract liquid was analyzed by high performance liquid chromatography-mass spectrometry (HPLC-MS) after being concentrated by 100 times. RESULT: Under the optimal condition of high-pressure solid phase extraction-high performance liquid chromatography-mass spectrometry, 10 components were rapidly identified from monoammonium glycyrrhizinate raw materials. Among them, the chemical structures of six micro-constituents were identified as 3-O-[beta-D-glucuronopyranosyl-beta-D-glucuronopyranosyl]-30-0-beta-D-apiopyranosylglycyrrhetic/3-O- [P-D-glucuronopyranosyl-beta-D-glucuronopyranosyl]-30-O-beta-D-arabinopyranosylglycyrrhetic, glycyrrhizic saponin F3, 22-hydroxyglycyrrhizin/18alpha-glycyrrhizic saponin G2, 3-O-[beta-D-rhamnopyranosyl]-24-hydroxyglycyrrhizin, glycyrrhizic saponin J2, and glycyrrhizic saponin B2 by MS(n) spectra analysis and reference to literatures. Four main chemical components were identified as glycyrrhizic saponin G2, 18beta-glycyrrhizic acid, uralglycyrrhizic saponin B and 18alpha-glycyrrhizic acid by liquid chromatography, MS(n) and ultraviolet spectra information and comparison with reference substances. CONCLUSION: The method can be used to identify chemical constituents in monoammonium glycyrrhizinate quickly and effectively, without any reference substance, which provides basis for quality control and safe application of monoammonium glycyrrhizinate-related products.