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61.
An optimized HPLC method for the quantification of metoclopramide (MCP) in human plasma and urine is described. MCP and internal standard are extracted from alkalinized substrate into diethyl ether and back-extracted into dilute acid. The analytes are separated with a ternary mobile phase at cyanopropyl-silica and detected at 312 nm (UV detection). The lower limit of quantification is 0.5 ng/ml in plasma and 50 ng/ml in urine. Optimization of extraction, chromatography, and detection is discussed. The method is selective to numerous common drug substances with excellent accuracy and precision data. After validation, the method is applied to the samples of a pharmacokinetic study. Pharmacokinetic parameters indicate the need for a sophisticated method as tool for optimization of metoclopramide formulations. 相似文献
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基因工程技术已经成为研究和生产重组人血清白蛋白(rHSA)替代人血清白蛋白(HSA)的重点技术,而白蛋白的纯化则是该技术的关键。本文主要介绍了从转基因猪血中纯化rHSA的一种新方法,即热乙醇沉淀与多级色谱分离相结合的rHSA纯化方法。热乙醇沉淀法可从猪血浆中获得rHSA粗提取液,此时rHSA的纯度可达69.5%,回收率达51.3%。进一步采用多级色谱分离法,即阴离子交换色谱和反相色谱法进一步纯化,得到rHSA的最终纯度约为100.0%,总回收率为41.1%。该方法为从转基因猪血浆中大规模纯化用于临床和生化研究的高纯度rHSA提供可能,同时也为rHSA替代HSA奠定了基础。 相似文献
64.
Sun Y Irie M Kishikawa N Wada M Kuroda N Nakashima K 《Biomedical chromatography : BMC》2004,18(8):501-507
A highly sensitive HPLC method was developed for the determination of xenoestrogenic compound, bisphenol A (BPA) in human breast milk samples. After a two-step liquid-liquid extraction, BPA was derivatized with fluorescent labeling reagent, 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride (DIB-Cl). The excess fluorescent reagent could be removed effectively using a column-switching system. The separation of DIB-BPA from endogenous materials in milk was carried out on two C(18) columns and fluorescence intensity was monitored at 475 nm with the excitation of 350 nm. A good linearity (r = 0.994) was observed of BPA in the concentration range of 0.2-5.0 ng mL(-1) in breast milk, and the detection limit was 0.11 ng mL(-1) at a signal-to-noise ratio of 3. Intra- and inter-day precision (RSD, %) were less than 8.7 and 10.4, respectively. Twenty-three breast milk samples of healthy lactating women were analyzed for the BPA concentration; the mean value was 0.61 +/- 0.20 ng mL(-1), with no correlation to the lipid content of milk samples. 相似文献
65.
食物中的钼与人体健康 总被引:5,自引:0,他引:5
综述了食物中钼与人体健康之间的关系.主要包括常见食物中的钼含量,钼在人体中的代谢,钼的生物学功能以及钼对人体健康的影响等. 相似文献
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Summary The native enantioselectivity in binding of human serum albumin (HSA) towards 2-aryl propionic acid non-steroidal anti-inflammatory drugs (2-APA-NSAIDs, the profens) was found to be preserved when the protein was immobilized within a commercially available diol high-performance liquid chromatographic column. High capacity factors were obtained, reflecting the previously observed extensive binding of the 2-APA-NSAIDs to free HSA. The capacity factors were modified by the addition of octanoic acid to the mobile phase. Chiral resolution of the enantiomers of all nine 2-APA-NSAIDs studied was achieved. Preliminary studies show that in addition to being a useful chiral analytical tool for this therapeutically important series of compounds, the HSA chiral stationary phase may provide useful information on the affinity and binding mechanism of small molecules to HSA. 相似文献
68.
Proteins with molecular mass (M(r)) <20 kDa are often poorly separated in 2-D sodium dodecyl sulfate polyacrylamide gel electrophoresis. In addition, low-M(r) proteins may not be readily identified using peptide mass fingerprinting (PMF) owing to the small number of peptides generated in tryptic digestion. In this work, we used a 2-D liquid separation method based on chromatofocusing and non-porous silica reversed-phase high-performance liquid chromatography to purify proteins for matrix-assisted laser desorption/ionization time-of-flight mass spectrometric (MALDI-TOFMS) analysis and protein identification. Several proteins were identified using the PMF method where the result was supported using an accurate M(r) value obtained from electrospray ionization TOFMS. However, many proteins were not identified owing to an insufficient number of peptides observed in the MALDI-TOF experiments. The small number of peptides detected in MALDI-TOFMS can result from internal fragmentation, the few arginines in its sequence and incomplete tryptic digestion. MALDI-QTOFMS/MS can be used to identify many of these proteins. The accurate experimental M(r) and pI confirm identification and aid in identifying post-translational modifications such as truncations and acetylations. In some cases, high-quality MS/MS data obtained from the MALDI-QTOF spectrometer overcome preferential cleavages and result in protein identification. 相似文献
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