Chunxiang Xu

Ningbo Institute of Product Quality, Ning-po, Zhejiang Sheng, China

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Publications (3)6.48 Total impact

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    ABSTRACT: Iron is a challenging element due to its high background in various matrixes including blood, tissues even in the air and it is urgent to develop a method for the accurate determination of iron in bio-samples. After optimization of mass spectrometric conditions using collision cell technology and compensating for interference using a mathematical correction equation, an inductively coupled plasma mass spectrometry (ICP-MS) method for the quantitative determination of (58)Fe originating from hemin extrinsically labeled avoiding endogenous interference was developed. After a single step of dilution, analysis of each sample was completed within 1.5min. The assay was linear in the concentration range from 0.005 to 1.0μg/ml. The precisions and accuracies determined within three consecutive days were in acceptable limits and there was no significant matrix effect. The optimized method was successfully applied to a pharmacokinetic study of (58)Fe originating from hemin extrinsically labeled and iron absorption measured in rats was 1.07%. Those indicated that extrinsically label techniques in combination with ICP-MS will become a new tool for the analysis of iron preparations and other endogenous substances.
    No preview · Article · Sep 2013 · Journal of pharmaceutical and biomedical analysis
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    ABSTRACT: Hemin, iron (III) protoporphyrin chloride (IX), as a stable form of heme iron, has been used in iron absorption studies. The aim of the present study was to elucidate the influences of body iron status and three dietary factors (green tea extract, ascorbic acid, and calcium) on the pharmacokinetics of hemin using stable isotope labeling methods followed by ICP-MS measurement. In this study, a rapid, sensitive, and specific ICP-MS method for the determination of 58Fe originating from hemin in rat plasma was developed and a rat model of iron deficiency anemia was established. It was found that hemin iron absorption increased significantly under iron deficiency anemia status, with AUC0−t and AUC0–∞ showing significant increase in anemic rats compared to normal ones. Green tea extract strongly inhibited hemin iron absorption in both normal rats and iron-deficient rats. In normal rats administered with green tea extract, C max resulted significantly reduced, whereas in anemic rats administered with green tea extract both AUC0−t and AUC0–∞ were reduced. On the other hand, ascorbic acid significantly affected hemin iron absorption only in iron-deficient rats, in which C max showed a significant increase. Interestingly, calcium slowed down the hemin iron absorption rate in normal rats, MRT0–t being significantly different in calcium-treated animals compared to untreated ones. This trend also appeared in the iron-deficient group but it did not reach statistical significance. Our data suggest that the mechanism of hemin iron absorption is regulated by body iron status and dietary factors can influence hemin iron absorption to varying degrees. Moreover, these results may also have general implication in the iron deficiency treatment with iron supplements and fortification of foods.
    No preview · Article · Apr 2013 · Biological trace element research
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    ABSTRACT: Dicycloplatin, as a new antitumor supramolecule, was considered to have higher solubility and higher stability compared with carboplatin. The aim of the present study was to evaluate the pharmacokinetic characteristics of platinum originating from dicycloplatin. A rapid, sensitive, and specific method with inductively coupled plasma mass spectrometry (ICP-MS) has been developed for the determination of platinum in bio-samples. The study was performed in male rats and dogs at a single dose of 10 and 5 mg kg(-1) separately by intravenous injection. Pharmacokinetic parameters were calculated by non-compartmental method, and the dose of platinum was used in the calculation of these parameters. Results showed that plasma concentrations of platinum began to decrease rapidly initially but decline slowly with a long terminal phase. The mean half-life was 27.39 and 100.98 and clearance was 0.77 and 0.08 L/h/kg for rats and dogs separately. Tissue distribution showed that platinum originating from dicycloplatin had a certain distribution in testis and prostate. Plasma protein binding proportion of platinum was increased with time. In conclusion, this research investigated the pharmacokinetic characteristics including plasma kinetics, tissue distribution, and plasma protein binding of platinum originating from dicycloplatin in rats and dogs in detail for the first time by ICP-MS.
    No preview · Article · Feb 2012 · Biological trace element research