Determination of vitamin D in oily drops using a column-switching system with an on-line clean-up by supercritical fluid chromatography.

A column-switching system, composed of supercritical fluid chromatography (SFC) and reverse phase liquid chromatography/mass spectrometry (RPLC/MS) was developed for the analysis of vitamin D in oily and fatty matrices. The SFC with the similar retention behavior as normal-phase liquid chromatography (NPLC), was applied for an on-line clean-up of oily and fatty samples, then followed by separation and detection using a reverse-phase LC-MS/MS. Three SFC columns packed with materials of different functional groups (Silica, NH2, Diol) were compared and the column with diol groups, on which the retention time of vitamin D was the longest, was finally selected for purification of the samples. 100% methanol was chosen to carry vitamin D from the clean-up column to the pre-treatment column. It was also used as the mobile phase for the separation of vitamin D on a reverse phase C18 column. Vitamin D2 and D3 were baseline separated by using this system. The linearity was calculated with a value of coefficient of determination (r2) ≥ 0.998. The linear range is from 20 ng/mL to 200 ng/mL. Two kinds of liquid vitamin D3 supplements (Baby Ddrops and Vitamin AD drops) were directly analyzed using this system without any fussy preparation procedure. The limit of detection (LOD) for vitamin D3 in the two oily samples was estimated to be 10 ng/mL. The relative standard deviations (RSD) of intra- and inter-day precision, repeatability were 1.47%, 2.43% and 1.59% for Baby Ddrops and 5.76%, 8.24% and 5.86% for Vitamin AD drops. The recoveries vary between 84.3% and 102.8% with 7.1% RSD for Baby Ddrops and 90.8-109.6% with 5.83% RSD for Vitamin AD drops, respectively. These results suggest that the method based on the SFC-RPLC/MS column-switching system is simple and suitable for analysis of vitamin D in oily and fatty samples.

A study of peritoneal metastatic xenograft model of colorectal cancer in the treatment of hyperthermic intraperitoneal chemotherapy with Raltitrexed.

Peritoneal metastasis of colorectal cancer is one of the most incident and fateful diseases among relapse cases. It shows a certain resistance to systemic chemotherapy. The perfusion system in clinic is complex and hard to be used in fundamental researches. This study aims at evaluating the effect of an improved hyperthermic intraperitoneal chemotherapy with Raltitrexed used in tumor-bearing mice with peritoneal metastatic colorectal carcinoma. The results showed that no severe adverse effect was observed. All control animals developed extensive peritoneal and mesenteric metastatic nodes. Tumor sites in the treatment groups were reduced significantly. The administration dose of Raltitrexed influenced concentration in systemic blood and peritoneal tissues. Temperature promoted the intracellular absorption of Raltitrexed significantly. Our findings reveal that hyperthermic intraperitoneal chemotherapy is an efficient therapy in treating peritoneal metastatic carcinoma in nude mice. It can effectively reduce the extension of carcinoma cells from macro and micro examination. The combination of hyperthermia and Raltitrexed resulted in an improved therapeutic effect on animal models.

Chemical analysis of Eriocaulon buergerianum and adulterating species by high-performance liquid chromatography with diode array detection and electrospray ionization tandem mass spectrometry.

Eriocaulon buergerianum Koern. is the botanical source for the Chinese herbal medicine Gu-Jing-Cao. Other Eriocaulon species are also used as the same herb in local areas and are difficult to be differentiated. In order to improve the quality control of Gu-Jing-Cao, chemical constituents of E. buergerianum and adulterating species were analyzed by high-performance liquid chromatography with diode array detection and electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS(n)). The 70% methanol extracts were separated on a Zorbax SB-C(18) column and eluted with acetonitrile-water (each containing 0.1% formic acid). The compounds were identified by ion-trap mass spectrometry in both positive and negative ion modes. From E. buergerianum, E. faberi, E. sexangulare and E. cinereum, a total of 72 compounds were characterized, including 37 flavonols, 6 flavones, 4 isoflavones, 6 xanthones, 14 naphthopyranones, 3 phenolic acids, and 2 other flavonoids. Chemical variation of these four species were studied at three tiers, HPLC fingerprinting, quantitation of six major flavonoids, and semi-quantitative analysis of all characterized compounds, in combination with principal component analysis. E. buergerianum contained abundant flavonols and naphthopyranones, with minor flavones and xanthones; E. cinereum contained abundant isoflavones and flavones, together with few naphthopyranones; E. sexangulare was rich in flavones; and E. faberi contained abundant xanthones. Based on the above chemical analysis, E. buergerianum could be explicitly differentiated from the adulterating species, and the botanical species of 13 commercial batches of Gu-Jing-Cao were identified correctly. This is the first report on comprehensive chemical analysis of Eriocaulon species.

Protective effects of echinacoside on carbon tetrachloride-induced hepatotoxicity in rats.

The aim of this study was to investigate the possible protective effects of echinacoside, one of the phenylethanoids isolated from the stems of Cistanches salsa, a Chinese herbal medicine, on the free radical damage of liver caused by carbon tetrachloride in rats. Treatment of rats with carbon tetrachloride produced severe liver injury, as demonstrated by dramatic elevation of serum ALT, AST levels and typical histopathological changes including hepatocyte necrosis or apoptosis, haemorrhage, fatty degeneration, etc. In addition, carbon tetrachloride administration caused oxidative stress in rats, as evidenced by increased reactive oxygen species (ROS) production and MDA concentrations in the liver of rats, along with a remarkable reduction in hepatic SOD activity and GSH content. However, simultaneous treatment with echinacoside (50mg/kg, intraperitoneally) significantly attenuated carbon tetrachloride-induced hepatotoxicity. The results showed that serum ALT, AST levels and hepatic MDA content as well as ROS production were reduced dramatically, and hepatic SOD activity and GSH content were restored remarkably by echinacoside administration, as compared to the carbon tetrachloride-treated rats. Moreover, the histopathological damage of liver and the number of apoptotic hepatocytes were also significantly ameliorated by echinacoside treatment. It is therefore suggested that echinacoside can provide a definite protective effect against acute hepatic injury caused by CCl(4) in rats, which may mainly be associated with its antioxidative effect.