Surface characteristics and in vitro biocompatibility of titanium preserved in a vitamin C-containing saline storage solution.

The purpose of this study is to explore a storage solution for titanium implants and investigate its osteogenic properties. The commercial pure titanium (cp-Ti) surface and double-etched (SLA) titanium surface specimens were preserved in air, saline, 10 mM Vitamin C (VitC)-containing saline and 100 mM VitC-containing saline storage solutions for 2 weeks. The surface microtopography of titanium was observed by scanning electron microscopy (SEM), the surface elemental compositions of the specimens were analyzed by Raman and X-ray photoelectron spectroscopy (XPS), and water contact angle and surface roughness of the specimens were tested. The protein adsorption capacity of two titanium surfaces after storage in different media was examined by BCA kit. The MC3T3-E1 osteoblasts were cultured on two titanium surfaces after storage in different media, and the proliferation, adhesion and osteogenic differentiation activity of osteoblasts were detected by CCK-8, laser confocal microscope (CLSM) and Western blot. The SEM results indicated that the titanium surfaces of the air group were relatively clean while scattered sodium chloride or VitC crystals were seen on the titanium surfaces of the other three groups. There were no significant differences in the micromorphology of the titanium surfaces among the four groups. Raman spectroscopy detected VitC crystals on the titanium surfaces of two experimental groups. The XPS, water contact angle and surface roughness results suggested that cp-Ti and SLA-Ti stored in 0.9% NaCl and two VitC-containing saline storage solutions possessed less carbon contamination and higher surface hydrophilicity. Moreover, the protein adsorption potentials of cp-Ti and SLA-Ti surfaces were significantly improved under preservation in two VitC-containing saline storage solutions. The results of in vitro study showed that the preservation of two titanium surfaces in 100 mM VitC-containing saline storage solution upregulated the cell adhesion, proliferation, osteogenic related protein expressions of MC3T3-E1 osteoblasts. In conclusion, preservation of cp-Ti and SLA-Ti in 100 mM VitC-containing saline storage solution could effectively reduce carbon contamination and enhance surface hydrophilicity, which was conducive to osteogenic differentiation of osteoblasts.

Comparative analysis of chemical constituents and bioactivities of the extracts from leaves, seed coats and embryoids of Ginkgo biloba L.

A total of 25 compounds including terpenoids, flavonoids, biflavonoids and ginkgolic acids were identified and quantified with a reliable, simple, and simultaneous method from Ginkgo leaves, seed coats and embryoids with different tree ages (approximately identified as 25, 500, 1000 and 2000 years). Leaves had the highest amount of total bioactive compounds. Seed coats had moderate contents of flavonoids, which was 15 times higher than embryoids. Furthermore, the effects of tree ages on bioactive compounds differ in three parts. The contents of bilobalide, ginkgolide J, ginkgolide C, ginkgolide B, ginkgolide A in embryoids and seed coats were highest from 500-year-old tree, while in leaves were highest from 25-year-old tree. This work first investigated the extensive bioactive compounds in ginkgo leaves, seed coats and embryoids from Ginkgo trees older than 500-year, it gives good reference for making better use of Ginkgo products.