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A rapid, accurate, and high performance method of high resolution sector field inductively coupled plasma mass spectrometry (HR-ICP-MS) combined with a small-size sample (0.1 mL) preparation was established. The method was validated and applied for the determination of 16 selected plasma trace elements (Fe, Cu, Zn, Rb, B, Al, Se, Sr, V, Cr, Mn, Co, As, Mo, Cd, and Pb). The linear working ranges were over three intervals, 0-1 μg/L, 0–10 μg/L and 0–100 μg/L. Correlation coefficients (R 2) ranged from 0.9957 to 0.9999 and the limits of quantification (LOQ) ranged from 0.02 μg/L (Rb) to 1.89 μg/L (Se). The trueness (or recovery) spanned from 89.82% (Al) to 119.15% (Se) and precision expressed by the relative standard deviation (RSD %) for intra-day ranging from 1.1% (Zn) to 9.0% (Se), while ranged from 3.7% (Fe) to 12.7% (Al) for interday. A total of 440 plasma samples were collected from Chinese National Nutrition and Health Survey Project 2002 (CNNHS 2002), which represented the status of plasma trace elements for the children aged 3–12 years from China economical developed rural areas. The concentrations of 16 trace elements were summarized and compared by age groups and gender, which can be used as one of the basic components for the formulation of the baseline reference values of trace elements for the children in 2002.

Oral delivery, rather than parenteral administration, would be beneficial for treating diabetic mellitus owing to the need for a long-term regimen. The objectives of this study were to evaluate oral delivery tolerance and the effects on the bone of accumulated vanadium following the long-term administration of vanadyl acetylacetonate (VAC). Normal and diabetic rats were intragastrically administered VAC at a dose of 3 mg vanadium/kg body weight once daily for 35 consecutive days. VAC did not cause any obvious signs of diarrhea, any changes in kidney or liver, or deaths in any group. The phosphate levels in the bone were slightly increased, and the calcium levels in the bone were not obviously changed as compared with those of the rat group not receiving VAC. After administration of VAC, the decreased ultimate strength, trabecular thickness, mineral apposition rate, and plasma osteocalcin in diabetic rats were either improved or normalized, but reduced bone mineral density (BMD) in diabetic rats was not improved. None of the parameters evaluated in normal rats were altered. The results indicate that the oral VAC is tolerated and benefits the diabetic osteopathy of rats, but seems not to influence the bone of normal rats. They also suggest that VAC improves diabetes-related bone disorders, primarily by improving the diabetic state.

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The objective of this research was to stabilize a heat-labile novel prodrug of Delta(9)-tetrahydrocannabinol (THC), THC-hemiglutarate (THC-HG), in polyethylene oxide (PEO) [PolyOx WSR N-80 (PEO N-80), MW 200,000 Daltons] polymeric matrix systems produced by hot-melt fabrication for systemic delivery of THC through the oral transmucosal route. For this purpose, the effects of processing conditions (processing temperature and heating duration), plasticizer type and concentration and storage conditions on the stability of the prodrug were investigated. The selected plasticizers studied included vitamin E succinate (VES), acetyltributyl citrate (ATBC), triethyl citrate (TEC), triacetin and polyethylene glycol 8000 (PEG 8000). Furthermore, the influence of plasticizer concentration on drug release was also studied. The stability of THC-HG in PEO matrices was influenced by all the aforementioned variables. Films processed at 110 degrees C for 7min were found to be favorable for hot-melt processing with a post-processing drug content of 95%, while significant degradation of THC-HG ( approximately 42%) was observed in those processed at 200 degrees C for 15min. The degradation of the prodrug during hot-melt fabrication and also upon storage was considerably reduced in the presence of the plasticizers investigated, VES being the most effective. Modulation of the microenvironmental pH to an acidic range via incorporation of citric acid in PEO-plasticizer matrices significantly improved the stability of the prodrug, with almost 90% of the theoretical drug remaining as opposed to only 15% remaining in PEO-only matrices when stored at 40 degrees C for up to 3 months. The release of drug from PEO matrices was influenced both by the plasticizer type and concentration. A faster release resulted from water-soluble plasticizers, PEG 8000 and triacetin, and with increasing concentration. However, a slower release was observed with an increase in concentration of water-insoluble plasticizers, VES and ATBC.