Simultaneous determination of four volatile compounds in rat plasma after oral administration of Shexiang Baoxin Pill (SBP) by HS-SPDE-GC-MS/MS and its application to pharmacokinetic studies.

In this study, a headspace, solid-phase dynamic extraction method coupled to gas chromatography-tandem mass spectrometry (HS-SPDE-GC-MS/MS) method was developed for the simultaneous determination of four volatile compounds, namely, isoborneol, borneol, muscone and cinnamaldehyde, in rat plasma after oral administration of Shexiang Baoxin Pill (SBP) using naphthalene as an internal standard (IS). The target compounds were extracted using an SPDE needle device coated with a poly (dimethylsiloxane) (PDMS) phase. The detection was achieved by GC-MS/MS in multiple reaction monitoring (MRM) mode. The optimised mass transition ion pairs (m/z) for quantitation were 95.1/67.1 for isoborneol and borneol, 85.0/67.0 for muscone, 131.0/77.0 for cinnamaldehyde and 128.1/102.1 for the IS. The parameters that affect the extraction ratio, such as the pre-incubation time, extraction temperature, number of extraction cycles, desorption volume and pH, were also optimised. The method was thoroughly validated with respect to specificity, linearity, precision, accuracy, recovery and stability. A sufficiently sensitive HS-SPDE-GC-MS/MS method was first developed in this study to determine the pharmacokinetics of volatile compounds found in rat plasma following oral administration of SBP. The method developed uses a simple procedure for plasma sample preparation and could be a promising tool for the analysis of complex volatile samples, such as traditional Chinese medicine (TCM).

[Analysis of muscone from serum and cerebrospinal fluid of rabbits after intragastric administration of tongqiao huoxue granules].

OBJECTIVE: To analyse the muscone from serum and cerebrospinal fluid (CSF) of rabbits after intragastric administration of Tongqiao Huoxue granules (TQHXG) and provide the partial experimental reference on laying down quality standard of preparation of formula and offer new ideas on studying the relation between pharmacodynamics and its effective component of formula. METHODS: Muscone from TQHXG was qualitative identified by the methods of thin-layer chromatography (TLC) and gas chromatography (GC). Muscone from blood and CSF of rabbits was examined by GC after intragastric administration of TQHXG. Compared with standard reference material of muscone, blank serum and blank CSF, the segmental component absorbed into CSF of rabbits was confirmed. RESULTS: Spots of TQHXG on the chromatomap showed the same colour at the corresponding locality of the standard reference material. Detected by GC, chromatographic peaks appeared at the retention time of 4.8 minute in the chromatomaps of the serum with TQHXG, the CSF with TQHXG and standard reference material of muscone, while there were no chromatographic peaks in the chromatomaps of the blank serum, the blank CSF and methanol at the same time. The ingredient corresponding the chromatographic peaks at the retention time of 4.8 minute in the chromatomaps of the serum, CSF with TQHXG should be muscone. CONCLUSION: Muscone from TQHXG could penetrate blood brain barrier and could be one index of quality standard of preparation of TQHXG.

Functionalization of cyclo-olefin polymer substrates by plasma oxidation: stable film containing carboxylic acid groups for capturing biorecognition elements.

Many current designs in biomedical diagnostics devices are based on the use of low cost, disposable, easy-to-fabricate chips made of plastic material, typically a cyclo-olefin polymer (COP). Low autofluorescence properties of such material, among others, make it ideal substrate for fluorescence-based applications. Functionalization of this plastic substrate for biomolecule attachment is therefore of great importance and the quality of films produced on such surface have often a significant influence on the performance of the device. In this communication we discuss the surface chemistry and some other characteristics of hydrophilic films, containing carboxylic acid functional groups, formed by plasma oxidation of COP and also films containing cross-linked, polymerized acryclic acid produced by sequential deposition of tetraorthosilicate and acrylic acid by plasma enhanced chemical vapor deposition (PECVD). Immobilization of labeled, single stranded DNA revealed high binding capacity for both coatings. To our best knowledge, this is the first example of direct immobilization of biomolecules on just plasma oxidized COP. Furthermore, more sophisticated treatment of the oxidized plastic substrate by PECVD with other organic precursors increased the binding capacity by some 40% than that of just plasma oxidized COP. The carboxy functionalized surfaces, due to the negative charge of the carboxy groups, showed very positive trends towards increasing the signal to noise ratio when charged biomolecules such as DNA, are used.

Pharmacokinetics of dezocine, a new analgesic: effect of dose and route of administration.

The pharmacokinetics of intravenous (IV) dezocine, and bioavailability of intramuscular (IM) and subcutaneous (SQ) dezocine, were evaluated in healthy male volunteers. Elimination half-life following 5, 10, and 20 mg IV doses averaged 2.6-2.8 h, and was independent of dose. Clearance decreased slightly, although significantly, with dose. After Deltoid IM injection, dezocine was rapidly absorbed (peak level: 0.6 h after dose), with bioavailability 97%. Thus dezocine has extensive distribution, high clearance and short half-life over a range of IV doses. It is rapidly and completely absorbed following IM or SQ administration.