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1.
Kenjiro Hattori Tomoko Takeuchi Mika Ogata Ayumi Takanohashi Katsuhiko Mikuni Katsuyoshi Nakanishi Hideo Imata 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):339-342
We obtained the association constants Ka of estrogen (E2) and environmental chemicals by the surface plasmon resonance (SPR) assay using the immobilized mono-6-O-α-maltosyl-β-CD (G2βCD) compared with the immobilized β-CD and the immobilized estrogen receptor (ER). The association behavior of G2βCD was shown as a ER model compound. The calibration curve was determined by the initial rate of association depending on
the various concentrations, and the minimum detectable concentrations in the order of parts per billion were calculated. The
SPR assay has advantages that the pre-treatment of the sample is not necessary and the immobilized ligand is stable and useful
for the repeated measurement. 相似文献
2.
二阶导数卷积伏安法应用于水稻中痛量雌雄激素的检测,具有快速,灵敏,干扰少的特点。本文以光周期敏感核不育水稻农垦58S为材料,以农垦58作对照,了叶焉和穗中雌,雄性激素的含量,研究了不同光周期条件下两类激素的变化。 相似文献
3.
17β‐Estradiol (E2) surface molecularly imprinted polymers have been prepared using functionalized monodispersed poly(glycidyl methacrylate‐co‐ethylene dimethacrylate) beads as a support. The resulting polymers were found to be uniform in size (5 μm), and the surfaces of the microspheres possessed large pore‐like structures. A chromatographic experiment demonstrated that the resulting microspheres exhibited high levels of recognition and selectivity toward the target molecule. The particles were employed as a novel sorbent in a molecularly imprinted SPE protocol. A method was then developed involving the combination of the pretreatment with HPLC to determine the levels of estrogen secreted from Michigan Cancer Foundation‐7 cells. The obtained results revealed that the extraction recoveries of E2 from real samples were in the range of 73.0–97.5% with RSDs of < 7.5% (n = 3). Calibration curves were established with R values > 0.9996 for concentrations in the range of 0.50–100.00 ng/mL. The LOD of this new method was 0.14 ng/mL. Compared with traditional C18 SPE agents, the particles showed high selectivity and extraction efficiency for E2 in the pretreatment process. The particles could therefore be used to determine trace estrogen in biological samples with a UV detector only. 相似文献
4.
We report liquid chromatographic separation with tandem mass spectrometry determination of 12 endogenous estrogens and their intact conjugates in blood and urine and its application to study effects of exemestane treatment on estrogen generation and metabolism in postmenopausal women with estrogen-dependent breast cancer. A 0.5 mL aliquot of each urine or serum sample is fractionated with solid phase extraction to a fraction of free estrogen and another fraction of their conjugates. The reversed phase LC/MS/MS determines dansylated estrogens with positive ionization and intact conjugates with negative ionization. The method provides reproducible separation and limit of detection as low as 1 pg mL−1 for free estrogens and 0.03 ng mg−1 creatinine for the conjugates in serum and urine samples. The method enabled us to acquire unique concentration profiles of 12 endogenous estrogens and their intact conjugates in 30 breast cancer patients before and after one month of exemestane treatment. Exemestane suppressed total serum and urinary estrogens by 11–97% (P < 0.0001) and 8.7–91% (P < 0.0001), respectively. Specifically, these data show that exemestane preferentially suppressed E1, E1-3S, E1-3G, and E2-17G more than other estrogens. Linear regression analysis of estrogen concentrations before and after treatment showed correlation coefficients of 0.8385 (n = 289, P < 0.0001) and 0.8863 (n = 360, P < 0.0001). This study provides urinary and blood estrogen concentration profiles in breast cancer patients to demonstrate the effect of exemestane on estrogen generation, supporting inhibition of aromatase activity. 相似文献
5.
表面活性剂存在下雌激素的直接电化学分析 总被引:5,自引:0,他引:5
雌二醇(E2)、雌三醇(E3)和雌酮(E1)是人体内3种重要的雌激素,它们在妇女的生殖生育方面发挥重要的作用。人体雌激素缺乏或过乘会导致诸多疾病。雌激素的检测方法已有不少报道,如气相色谱-质谱(GC-MS)、液相色谱(LC)以及化学发光免疫法等。E2,E1和E3的结构相似,且均具有疏水性及非电活性,用电化学直接测定十分困难,一般只能间接测定。本文报道了一种新的电化学分析方法。该方法对三种雌激素有十分灵敏的伏安响应,可用于微量测定。 相似文献
6.
In this study, a simple and efficient large volume injection gas chromatography–mass spectrometry (GC-MS) method, via a programmable-temperature
vaporizer (PTV) inlet, has been developed and applied in the determination of estrogens in environmental water samples without
a prior derivatization process. Three commonly used estrogens estrone, 17 β-estradiol and 17 α-ethynylestradiol were selected
as target compounds for this study. It has been demonstrated that the type of gas chromatograph liner and the initial inlet
temperature can greatly affect the response intensity of estrogens. Three different types of PTV liners have been studied;
the multibaffle liner generated the strongest response intensities towards the estrogen analytes. The results showed that
the response intensities of estrogens reduced sharply while the initial inlet temperature increased. Various instrument conditions
and sample preparation methods were studied in detail. The optimized method has been validated with good linearity, precision
and accuracy. The method detection limit of each estrogen was found to be 0.041 ng/L for estrone, 0.046 ng/L for 17 β-estradiol
and 0.031 ng/L for 17 α-ethynylestradiol. To the best of our knowledge, these results represent the best sensitivities achieved
for estrogens analyzed in water samples via traditional GC-MS method without a derivatization process. This method has been
successfully applied in the analyses of different water samples. 相似文献
7.
In this work, a novel method for the fabrication of magnetic carbon nanotubes based on 'aggregation wrap' was proposed. When carbon nanotubes and magnetic nanoparticles were vortically mixed in a solvent, the magnetic nanoparticles were wrapped into the carbon nanotube bundles that formed during the aggregation process, leading to the formation of magnetic carbon nanotubes. Thus, the resultant material can be separated from the solvent rapidly and conveniently by a magnet. Our investigation demonstrated that the 'aggregation wrap' mechanism for the preparation of magnetic composite is also applicable to other self-aggregated micro/nanomaterials, including graphene, graphite, C(60), etc. To testify the feasibility of the magnetic composites in sample preparation, the resultant magnetic carbon nanotubes were applied as sorbents for magnetic solid-phase extraction (MSPE) of estrogens in milk samples. Under optimized conditions, a rapid, convenient and efficient method for the determination of estrogens in milk samples was established by the combination of MSPE with high-performance liquid chromatography with fluorescence detector. The linearity range of the proposed method was 5-2000 μg/L with correlation coefficients (R) of 0.9983-0.9994. The limit of detection (LOD) for three estrogens ranged from 1.21 to 2.35 μg/L. The intra- and inter-day relative standard deviations (RSDs) were <9.3%. The reproducibility of the MSPE with different batches of magnetic carbon nanotubes was acceptable with RSD values <3.6%. 相似文献
8.
Higashi T Takayama N Nishio T Taniguchi E Shimada K 《Analytical and bioanalytical chemistry》2006,386(3):658-665
A practical procedure for determining estrogens in biological fluids has been studied using liquid chromatography–electron
capture atmospheric pressure chemical ionization–mass spectrometry combined with derivatization. Among the commercially available
reagents (4-nitrobenzoyl chloride, 2,4-dinitrofluorobenzene, 4-nitrobenzenesulfonyl chloride and 4-nitrobenzyl bromide), 4-nitrobenzenesulfonyl
chloride was of the most practical use; it rapidly and quantitatively reacted with estrogens and increased the detection responses
by 8–23 times. The derivatization method allowed the reproducible and accurate quantification of serum and urine estrone and
estradiol of a pregnant woman, which is useful for diagnosis of the fetoplacental function, with small amounts (10 μl) of
sample and a simple pretreatment procedure.
Tatsuya
Higashiis Associate Professor of the Laboratory of Clinical Analytical Sciences (Professor Kazutake Shimada’s research group) at
the Graduate School of Natural Science and Technology of Kanazawa University. He received the Japan Society for Analytical
Chemistry Award for Young Scientists in 2003 and the Pharmaceutical Society of Japan Award for Young Scientists in 2006. His
current research interests are the development of methods for increasing sensitivity in LC-MS to detect and characterize trace
amounts of biologically active steroids, such as estrogens, androgens and neuroactive steroids. 相似文献
9.
Wenger D Gerecke AC Heeb NV Naegeli H Zenobi R 《Analytical and bioanalytical chemistry》2008,390(8):2021-2029
An in vitro reporter gene assay based on human breast cancer T47D cells (ER-CALUX) was applied to examine the ability of diesel exhaust to induce or inhibit estrogen receptor (ER)-mediated gene expression. Exhaust from a heavy-duty diesel engine was either treated by iron- or copper/iron-catalyzed diesel particulate filters (DPFs) or studied as unfiltered exhaust. Collected samples included particle-bound and semivolatile constituents of diesel exhaust. Our findings show that all of the samples contained compounds that were able to induce ER-mediated gene expression as well as compounds that suppressed the activity of the endogenous hormone 17beta-estradiol (E2). Estrogenic activity prevailed over antiestrogenic activity. We found an overall ER-mediated activity of 1.63 +/- 0.31 ng E2 CALUX equivalents (E2-CEQs) per m(3) of unfiltered exhaust. In filtered exhaust, we measured 0.74 +/- 0.07 (iron-catalyzed DPF) and 0.55 +/- 0.09 ng E2-CEQ m(-3) (copper/iron-catalyzed DPF), corresponding to reductions in estrogenic activity of 55 and 66%, respectively. Our study demonstrates that both catalytic DPFs lowered the ER-mediated endocrine-disrupting potential of diesel exhaust. 相似文献
10.
We describe the development and validation of a high-resolution screening (HRS) platform which couples gradient reversed-phase
high-performance liquid chromatography (RP-HPLC) on-line to estrogen receptor α (ERα) affinity detection using fluorescence
polarization (FP). FP, which allows detection at high wavelengths, limits the occurrence of interference from the autofluorescence
of test compounds in the bioassay. A fluorescein-labeled estradiol derivative (E2-F) was synthesized and a binding assay was
optimized in platereader format. After subsequent optimization in flow-injection analysis (FIA) mode, the optimized parameters
were translated to the on-line HRS bioassay. Proof of principle was demonstrated by separating a mixture of five compounds
known to be estrogenic (17β-estradiol, 17α-ethinylestradiol and the phytoestrogens coumestrol, coumarol and zearalenone),
followed by post-column bioaffinity screening of the individual affinities for ERα. Using the HRS-based FP setup, we were
able to screen affinities of off-line-generated metabolites of zearalenone for ERα. It is concluded that the on-line FP-based
bioassay can be used to screen for the affinity of compounds without the disturbing occurrence of autofluorescence. 相似文献