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1.
龙耀庭 《分析化学》1993,21(10):1212-1219
本文综述了在DNA测序方面分析化学的最新进展,包括电泳,毛细管电泳(CE),质谱(MS),电喷雾电离-质谱(ESI-MS),荧光光谱、共振离子谱(RIS)和单分子测定,同时还叙述了两维技术和多段测序方法的进展。  相似文献   

2.
The biocatalytic production of flavor naturals that determine chemosensory percepts of foods and beverages is an ever challenging target for academic and industrial research. Advances in chemical trace analysis and post‐genomic progress at the chemistry–biology interface revealed odor qualities of nature’s chemosensory entities to be defined by odorant‐induced olfactory receptor activity patterns. Beyond traditional views, this review and meta‐analysis now shows characteristic ratios of only about 3 to 40 genuine key odorants for each food, from a group of about 230 out of circa 10 000 food volatiles. This suggests the foodborn stimulus space has co‐evolved with, and roughly match our circa 400 olfactory receptors as best natural agonists. This perspective gives insight into nature’s chemical signatures of smell, provides the chemical odor codes of more than 220 food samples, and beyond addresses industrial implications for producing recombinants that fully reconstruct the natural odor signatures for use in flavors and fragrances, fully immersive interactive virtual environments, or humanoid bioelectronic noses.  相似文献   

3.
元素医学就是在原子、分子生物学基础上,以元素平衡为核心,从事研究、观察和解决人类健康问题的一门学科。微量元素通过与蛋白质和其它有机基团结合,可以形成酶、激素和维生素等生物大分子。鉴于此,针对微量元素测定在生物技术实验中的应用进行探讨。  相似文献   

4.
液相色谱仪可应用于生物化学、生物医学、环境化学等方面的分析研究。随着现代医学的发展,采用液相色谱法进行生物技术研究已经成为一种常规方法。鉴于此,针对应用液相色谱法进行生物技术研究时出现的常见问题进行分析,并提出合理的解决办法。  相似文献   

5.
人体血液蛋白的毛细管电泳分析进展   总被引:4,自引:0,他引:4  
张滨  薛俊 《分析化学》1997,25(8):973-977
对近年来对毛细管电泳在血清蛋白、免疫蛋白、同工酶、脂蛋白、等人 血液蛋白检测上的应用和发展前景进行了综核实 。毛细管电泳以其高效,等特点很有可能成为未来临床实验室的一种不可缺少的分析技术。  相似文献   

6.
Innovation has frequently been described as the key to drug discovery. However, in the daily routine, medicinal chemists often tend to stick to the functional groups and structural elements they know and love. Blockbuster cancer drug Velcade (bortezomib), for example, was rejected by more than 50 companies, supposedly because of its unusual boronic acid function (as often repeated: “only a moron would put boron in a drug!”). Similarly, in the discovery process of the pan‐CDK inhibitor BAY 1000394, the unconventional proposal to introduce a sulfoximine group into the lead series also led to sneers and raised eyebrows, since sulfoximines have seldom been used in medicinal chemistry. However, it was the introduction of the sulfoximine group that finally allowed the fundamental issues of the project to be overcome, culminating in the identification of the clinical sulfoximine pan‐CDK inhibitor BAY 1000394. This Minireview provides an overview of a widely neglected opportunity in medicinal chemistry—the sulfoximine group.  相似文献   

7.
A novel HPLC-ESI-MS/MS method for simultaneous gonadotropin-releasing hormone (GnRH) analogs and somatostatin analog quantitation was developed and validated. The developed method was successfully applied to pharmacokinetic studies. The sample preparation process included solid-phase extraction (SPE). Effective chromatographic separation of the analytes and internal standard (dalargin) was achieved with a C18 column, using a gradient elution with two mobile phases: 0.1% v/v formic acid (aqueous solution) and 0.1% v/v formic acid (acetonitrile solution). The linearity of the method was demonstrated within a concentration range of 0.5–20 ng/mL, with correlation coefficients between 0.998–0.999 for goserelin, buserelin, triptorelin, and octreotide, respectively. The relative standard deviation (RSD, %) values for method accuracy and precision did not exceed 20% at the lower level of quantitation (LLOQ) or 15% at other concentration levels.  相似文献   

8.
Traditional analytical methods for thalassemia screening are needed to process complicated and time-consuming sample pretreatment. In recent decades, ambient mass spectrometry (MS) approaches have been proven to be an effective analytical strategy for direct sample analysis. In this work, we applied ambient MS with wooden-tip electrospray ionization (WT-ESI) for the direct analysis of raw human blood samples that were pre-identified by gene detection. A total of 319 whole blood samples were investigated in this work, including 100 α-thalassemia carriers, 67 β-thalassemia carriers, and 152 control healthy samples. Only one microliter of raw blood sample was directly loaded onto the surface of the wooden tip, and then five microliters of organic solvent and a high voltage of +3.0 kV were applied onto the wooden tip to generate spray ionization. Multiply charged ions of human hemoglobin (Hb) were directly observed by WT-ESI-MS from raw blood samples. The signal ratios of Hb chains were used to characterize two main types of thalassemia (α and β types) and healthy control blood samples. Our results suggested that the ratios of charged ions to Hb chains being at +13 would be an indicator for β-thalassemia screening.  相似文献   

9.
血液中苯丙氨酸的测定方法研究进展   总被引:3,自引:1,他引:3  
高效、简便、快速测定血液中苯丙氨酸含量在医学上尤其是对新生儿的苯丙酮尿症的筛查有着重要的意义;本文就血液中苯丙氨酸的测定方法研究进展进行了综述,内容包括:细菌抑制法、荧光法、高效液相色谱法、气相色谱—质谱联用、质谱—质谱联用、毛细管电泳、酶/比色法以及酶电极法等。  相似文献   

10.
Currently, diagnosing type 2 diabetes (T2D) is a great challenge. Thus, there is a need to find rapid, simple, and reliable analytical methods that can detect the disease at an early stage. The aim of this work was to shed light on the importance of sample collection options, sample preparation conditions, and the applied capillary electrophoresis bioanalytical technique, for a high-resolution determination of the N-glycan profile in human blood samples of patients with type 2 diabetes (T2D). To achieve the profile information of these complex oligosaccharides, linked by asparagine to hIgG in the blood, the glycoproteins of the samples needed to be cleaved, labelled, and purified with sufficient yield and selectivity. The resulting samples were analyzed by capillary electrophoresis, with laser-induced fluorescence detection. After separation parameter optimization, the capillary electrophoresis technique was implemented for efficient N-glycan profiling of whole blood samples from the diabetic patients. Our results revealed that there were subtle differences between the N-glycan profiles of the diabetic and control samples; in particular, two N-glycan structures were identified as potential glycobiomarkers that could reveal significant changes between the untreated/treated type 2 diabetic and control samples. By analyzing the resulting oligosaccharide profiles, clinically relevant information was obtained, revealing the differences between the untreated and HMG-CoA reductase-inhibitor-treated diabetic patients on changes in the N-glycan profile in the blood. In addition, the information from specific IgG N-glycosylation profiles in T2D could shed light on underlying inflammatory pathophysiological processes and lead to drug targets.  相似文献   

11.
Abstract

A liquid chromatographic method for the assay of the antiarrhythmic drug flecainide in plasma has been developed. The method is rapid, simple and with sufficient detection sensitivity to render it suitable for therapeutic drug monitoring. Flecainide and added internal standard, a non-fluorinated analogue, were extracted by a single ether extraction from alkalinized plasma followed by a back-extraction of the ether with dilute phosphoric acid. A portion of the acid extract was then applied directly to a 30 cm ODS column eluting isocratically with 30% acetonitrile in water containing 0.01M dibutylamine phosphate. Monitoring was by ultraviolet detection at 214 nm and the total run time was 8 min. This method is specific and can quantitate plasma levels to less than 30 ng/ml (free base) from 0.5 ml of plasma without interference from antiarrhythmic drugs commonly used in therapy.  相似文献   

12.
Molecular hydrogen has unique nuclear spin properties. Its nuclear spin isomer, parahydrogen (pH2), was instrumental in the early days of quantum mechanics and allows to boost the NMR signal by several orders of magnitude. pH2-induced polarization (PHIP) is based on the survival of pH2 spin order in solution, yet its lifetime has not been investigated in aqueous or biological media required for in vivo applications. Herein, we report longitudinal relaxation times (T1) and lifetimes of pH2 ( ) in methanol and water, with or without O2, NaCl, rhodium-catalyst or human blood. Furthermore, we present a relaxation model that uses T1 and for more precise theoretical predictions of the H2 spin state in PHIP experiments. All measured T1 values were in the range of 1.4–2 s and values were of the order of 10–300 minutes. These relatively long lifetimes hold great promise for emerging in vivo implementations and applications of PHIP.  相似文献   

13.
《Analytical letters》2012,45(5):757-766
Abstract

A high‐performance liquid chromatography (HPLC) method has been developed for the determination of ochratoxin A (OTA) in human blood serum. Samples were purified on a C18 solid phase extraction column. The developed method required a relatively low serum volume (0.5 ml). Significant correlation (r of 0.998) was found over the range from 0.10 to 8 ng/ml, with a detection limit of 0.1 ng/ml and better performance in terms of precision and accuracy. Mean recoveries at 0.5 and 2 ng/ml were respectively 69.7±1.2 and 71.9±2.8%. This method was used as a rapid and noninvasive tool to assess human exposure to OTA. Among 40 analyzed serum samples, 27.5% were found to contain OTA with levels going from 0.1 to 11.98 ng/ml with a mean concentration of 0.73±2.35 ng/ml.  相似文献   

14.
Background: Tetrabromobisphenol A (TBBPA) is the most commonly used brominated flame retardant (BFR) in the industry. TBBPA has been determined in environmental samples, food, tap water, dust as well as outdoor and indoor air and in the human body. Studies have also shown the toxic potential of this substance. In search of a better and less toxic BFR, tetrabromobisphenol S (TBBPS) has been developed in order to replace TBBPA in the industry. There is a lack of data on the toxic effects of TBBPS, while no study has explored apoptotic mechanism of action of TBBPA and TBBPS in human leukocytes. Methods: The cells were separated from leucocyte-platelet buffy coat and were incubated with studied compounds in concentrations ranging from 0.01 to 50 µg/mL for 24 h. In order to explore the apoptotic mechanism of action of tested BFRs, phosphatidylserine externalization at cellular membrane (the number of apoptotic cells), cytosolic calcium ion and transmembrane mitochondrial potential levels, caspase-8, -9 and -3 activation, as well as PARP-1 cleavage, DNA fragmentation and chromatin condensation in PBMCs were determined. Results: TBBPA and TBBPS triggered apoptosis in human PBMCs as they changed all tested parameters in the incubated cells. It was also observed that the mitochondrial pathway was mainly involved in the apoptotic action of studied compounds. Conclusions: It was found that TBBPS, and more strongly TBBPA, triggered apoptosis in human PBMCs. Generally, the mitochondrial pathway was involved in the apoptotic action of tested compounds; nevertheless, TBBPS more strongly than TBBPA caused intrinsic pathway activation.  相似文献   

15.
16.
《Electroanalysis》2004,16(5):399-403
The quantitative detection of cadmium in human blood is shown to be possible by anodic stripping voltammetry under conditions of insonation. An immersion horn probe is introduced into a thermostatted conventional three‐electrode cell opposite a Nafion‐coated mercury plated glassy carbon electrode. The enhanced mass transport associated with power ultrasound yields efficient preconcentration of the cadmium before it is detected using anodic differential‐pulse stripping voltammetry. Insonation further offers the crucial benefits of first surface activation and cleaning, helping to prevent electrode fouling by the organic components in blood and second fully equilibrating “free” and “bound” Cd2+ ions in the complex matrix. Acoustic streaming and cavitation promote the mass transport of cadmium to the surface of electrode, facilitating measurements in solutions of low cadmium concentration, where “silent” measurements fail to yield an analytical signal. The system is calibrated using standard micro additions of cadmium to give the total amount of cadmium in blood. The calibration plot, showing the dependence of the cadmium stripping peak height on cadmium concentration in 1 : 50 diluted blood samples, was linear in the range 1×10?10 M to 4×10?9 M Cd2+. The values of cadmium concentration obtained using sonoelectroanalytical methodology were compared with the results obtained by independent atomic absorption spectroscopy (AAS) measurements and good agreement was found.  相似文献   

17.
用气相色谱—质谱法测定人血中阿片类药物   总被引:1,自引:0,他引:1  
吴筠  王杉 《分析化学》1995,23(3):288-291
本文用固-液提取,MSTFA-MBTFA混合衍生化,经GC/MSD分析,建立了检测人血中阿片类药物的快速、稳定、灵敏、准确的分析方法。  相似文献   

18.
Chlorophyll a and, in particular, bacteriochlorophyll a derivatives are promising candidates for photosensitizers in photodynamic therapy. The distribution of 21 (bacterio)chlorophyll derivatives among human blood plasma fractions was studied by iodixanol gradient ultracentrifugation and in situ absorption spectroscopy. Modifications of the natural pigments involved the central metal (Mg2+, Zn2+, Pd2+, none), the isocyclic ring (closed, open and taurinated), substituents at C-3 (vinyl, acetyl, 1-hydroxyethyl) and C-173 (phytyl ester, free acid). Cellular blood components bound only a small fraction of the pigments. Distribution among low-density lipoproteins (LDL), high-density lipoproteins (HDL) and high-density proteins (HDP) of the plasma was influenced as follows: (1) application in Cremophor® EL slightly altered pigment distribution by lipoprotein modification, (2) only very polar pigments with multiple hydrophilic substituents showed substantial HDP binding, (3) the presence of the esterifying alcohol at C-173 caused enrichment in LDL, this was more pronounced with bacteriochlorophylls than with chlorophylls, (4) substituents at C-3 had only little influence on the distribution, (5) Zn2+-complexes were enriched in HDL compared to Mg2+ and Pd2+ complexes, indicating specific binding of the former. Equilibration of pigments among the different fractions was largely complete within 3 h.  相似文献   

19.
《Analytical letters》2012,45(13):2452-2464
Abstract

A high-performance liquid chromatography method for determination of ochratoxin A (OTA) in human blood serum has been validated. A liquid-liquid partition, solid-phase extraction and immunoaffinity cleanup was applied for OTA extraction from 0.5 mL of serum. Significant correlation (r = 0.998) was found over the range from 0.1 to 8 ng/mL, with better performance in terms of accuracy, precision, and selectivity. Validation was made with human serum spiked at two levels, 0.5 and 2.0 ng/mL,26 and natural contaminated serum. Average recoveries of OTA using different extraction methods ranged from 58.48 ± 4.56 to 94.85 ± 3.52%. Immunoaffinity cleanup showed a better recovery rate, with a lower detection limit validated at 0.1 ng/mL. The cited method can be used as a rapid and noninvasive tool to assess human and animal exposure to OTA.  相似文献   

20.
为建立一种快速、简便、灵敏的分光光度法测定全血中微量铁,在非离子型表面活性剂聚氧乙烯月桂醚(Brij-3 5 )及聚氧乙烯异辛基苯基醚(TritonX -1 0 0 )存在下,用2 (5 硝基2 吡啶偶氮) 5 [N 正丙基 N (3 磺酸丙基)氨基]苯酚二钠(简称Nitro -PAPS)作显色剂直接光度法测定全血中微量铁。结果表明,该法在pH 4 0的乙酸乙酸钠缓冲液中,以5 90nm为测定波长,可直接测定全血中微量铁,本法线性范围为0~2 2 7μg/mL ,表观摩尔吸光系数为9 97×1 0 4L/(mol·cm) ,回收率为97 5 %~1 0 1 8%。结论:该法具有操作快速、简便、结果灵敏可靠等优点,适合临床医疗、预防保健等应用,值得推广。  相似文献   

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