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991.
Derliane Oliveira Sook Fan Yap Siripan Wongwanich Baldip Khan Juan Cristina 《Accreditation and quality assurance》2010,15(2):89-97
Nucleic acid-based technologies have opened new perspectives in diagnosis, prognosis, and treatment in clinical medicine.
To maintain patient confidence in this rapidly expanding field and to provide the highest standard of analysis, strict laboratory
quality assurance procedures must be followed. While impressive break-through are taking place in this field, the need for
an appropriate and suitable quality assurance (QA) plan for nucleic acid-based diagnostic laboratories must be a top priority.
In this study, we developed a systematic QA plan for this kind of diagnostic laboratories that would enable us to assure the
highest quality standards of their services. We focus on those labs that would like to start introducing a quality system
for the first time and discuss the most appropriate ways to pave the way to implement a QA plan from the beginning. This QA
plan is suitable for any nucleic acid-based techniques laboratory regardless of the field or services provided. 相似文献
992.
Jun Zhang Ramona Rodila Eric Gage Mathew Hautman Leimin Fan Linda L. King Huaiqin Wu Tawakol A. El-Shourbagy 《Analytica chimica acta》2010,661(2):167-172
Simvastatin (SS) is an effective cholesterol-lowering medicine, and is hydrolyzed to simvastatin acid (SSA) after oral administration. Due to SS and SSA inter-conversion and its pH and temperature dependence, SS and SSA quantitation is analytically challenging. Here we report a high-throughput salting-out assisted liquid/liquid extraction (SALLE) method with acetonitrile and mass spectrometry compatible salts for simultaneous LC-MS/MS analysis of SS and SSA. The sample preparation of a 96-well plate using SALLE was completed within 20 min, and the SALLE extract was diluted and injected into an LC-MS/MS system with a cycle time of 2.0 min/sample. The seamless interface of SALLE and LC-MS eliminated drying down step and thus potential sample exposure to room or higher temperature. The stability of SS and SSA in various concentration ratios in plasma was evaluated at room and low (4 °C) temperature and the low temperature (4 °C) was found necessary to maintain sample integrity. The short sample preparation time along with controlled temperature (2-4 °C) and acidity (pH 4.5) throughout sample preparation minimized the conversion of SS → SSA to ≤0.10% and the conversion of SSA → SS to 0.00% The method was validated with a lower limit of quantitation (LLOQ) of 0.094 ng mL−1 for both SS and SSA and a sample volume of 100 μL. The method was used for a bioequivalence study with 4048 samples. Incurred sample reproducibility (ISR) analysis of 362 samples from the study exceeded ISR requirement with 99% re-analysis results within 100 ± 20% of the original analysis results. 相似文献
993.
Zenzen Fan Chien-Hung Lin Hung-Wei Chang Takashi Kaneta Cheng-Huang Lin 《Journal of chromatography. A》2010,1217(5):755-760
A novel Hadamard transform-gas chromatography/mass spectrometry (HT-GC/MS) system equipped with on-line sample collection systems is described. A Hadamard-injector was successfully designed and then coupled with an on-line adsorption/desorption system for detecting volatile organic compounds (VOCs) and a supercritical fluid extraction (SFE) system, respectively, by HT-GC/MS. Six VOCs and three pesticides were used as model compounds. In the former case, an activated-charcoal trap was used to trap VOCs from the indoor air. After 10 L of indoor air had passed through the trap, the condensed components were heated and simultaneously injected into the GC column through the Hadamard-injector, based on Hadamard codes. In a second experiment, a sample of rice was spiked with three types of pesticides and the sample then extracted using a commercially available supercritical fluid extractor. After extraction, the extracted components were transferred to a holding tank and simultaneously injected into the GC column also using the Hadamard-injector. The findings show that, in both cases, the combination of on-line sample collection methods and the use of the Hadamard transform resulted in improved sensitivity and detection. Compared to the single injection used in most GC/MS systems, the signal-to-noise (S/N) ratios were substantially improved after inverse Hadamard transformation of the encoded chromatogram. 相似文献
994.
A novel two-dimensional coordination polymer [Ba2(phen)4(tp)2]n(phen=1,10-phenanthroline,tp=terephthalic acid) has been synthesized with tp as bridge ligands and structurally determined by X-ray crystallography.The crystal belongs to the monoclinic system,space group C2/c,with a=18.877(4),b=18.489(4),c=15.658(3),β=103.61(3)o,V=5311.5(19)3,C32H20O4N4Ba,Mr=661.86,Z=8,F(000)=2624,μ=1.542mm-1,Dc=1.655 g/cm3,the final R= 0.0228 and wR=0.0554 for 6063 observed reflections(I2σ(I)).The structural analysis shows that each tp ligand bridges barium atoms to form a two-dimensional infinite layer.There are aromatic π-π stacking interactions between neighboring layers,and aromatic π-π interactions further extend such layers into a three-dimensional supramolecular framework. 相似文献
995.
建立了免疫亲和柱净化-柱后电化学衍生-高效液相色谱结合荧光光度法检测花生酱中4种黄曲霉毒素(B1、B2、G1和G2)的方法。样品经过体积分数为60%的甲醇提取,通过免疫亲和柱净化后,以KobraCell装置柱后衍生,高效液相色谱法分离定量。黄曲霉毒素B1、B2、G1和G2能达到完全的基线分离,检测限分别为0.5、0.15、0.5和0.15μg/kg,线性相关系数0.999,回收率可达74.2%~96.5%,相对标准偏差低于11%。该方法能够满足花生酱中黄曲霉毒素检测的需要。 相似文献
996.
高效液相色谱-串联质谱测定猪肉中3种β-受体激动剂残留量 总被引:3,自引:0,他引:3
建立一种同时测定猪肉中3种β-受体激动剂残留量的高效液相色谱-电喷雾串联质谱(HPLC-ESI-MS/MS)确证分析方法。样品经β-葡萄糖醛酸酶/芳基硫酸酯酶酶解、乙酸铵缓冲液提取和MCX固相萃取柱净化,采用Agilent ZorbaxSB-C18(2.1mm×150mm,3.5μm)色谱柱,0.1%的甲酸水溶液、甲醇和乙腈作为流动相进行洗脱,高效液相色谱分离,电喷雾离子源电离,正离子多反应监测模式进行检测,内标法定量。3种药物在0.05~1μg/kg浓度范围内线性良好,相关系数r均大于0.999,0.05、0.1、0.5μg/kg3个浓度水平的添加回收率在89.7%~106.7%之间,相对标准偏差为2.4%~8.6%,3种药物的定量限均为0.05μg/kg。方法适用于猪肉中β-受体激动剂残留的确证分析。 相似文献
997.
Syntheses,Structural Characterization and Thermoanalysis of Transition-Metal Compounds Derived from 3,5-Dinitropyridone 总被引:1,自引:0,他引:1
Rong Fan Qiu-Ping Zhou Guo-Fang Zhang Mei-Yu Cai Ping Li Li-Hua Gan Feng-Qi Zhao Ji-Zhen Li Xue-Zhong Fan Seik Weng Ng 《Journal of chemical crystallography》2010,40(3):266-271
Abstract
Nine metal compounds of Mn(II), Zn(II) and Cd(II) derived from dinitropyridone ligands (3,5-dinitropyrid-2-one, 2HDNP; 3,5-dinitropyrid-4-one, 4HDNP and 3,5-dinitropyrid-4-one-N- hydroxide, 4HDNPO) were characterized by elemental analysis, FT-IR and partly by TG-DSC. Three of which were further structurally characterized by X-ray single-crystal diffraction analysis. The structures of the three compounds, Mn(4DNP)2(H2O)4, 4, Zn(4DNPO)2(H2O)4, 8, and Cd(4DNPO)2(H2O)4, 9, crystallize in the monoclinic space group P2(1)/n and Z = 2, with a = 8.9281(9), b = 9.1053(9), c = 10.6881(11) Å, β = 97.9840(10)° for 4; a = 8.4154(7), b = 9.9806(8), c = 10.5695(8) Å, β = 97.3500(10)° for 8; a = 8.5072(7), b = 10.2254(8), c = 10.5075(8) Å, β = 96.6500(10)° for 9. All three complexes are octahedral consisting of four equatorial water molecules, and two nitrogen or oxygen donor ligands (DNP or DNPO). The abundant hydrogen-bonding and π-π stacking interactions seem to contribute to stabilization of the crystal structures of the compounds. The TG-DTG results revealed that the complexes showed a weight loss sequence corresponding to all coordinated water molecules, nitro groups, the breaking of the pyridine rings and finally the formation of metal oxides. 相似文献998.
999.
Solid-state dye samples based on modified polymethyl methacrylate with methanol (MPMMA) doped with pyrromethene 567 (PM567)
were first prepared. The effects of volume percentage of methanol on the laser performances of the samples, including spectra
properties, slope efficiency and photostability were studied. The highest slope efficiency 66.39% was obtained in the sample
(MMA:methanol = 16:4). Pumping the samples at a repetition rate of 5 Hz with a pulse energy as high as 100 mJ (the fluence
was 0.26 J/cm2), the output energy dropped to half of its initial value after approximate 156720 shots and the corresponding normalized
photostability reached 101.86 GJ/mol in the sample (MMA:methanol = 17:3). Our results indicate that it can obtain a high slope
efficiency and good photostability for a solid-state dye laser using MPMMA as solid hosts. 相似文献
1000.
Wang X. Li P. Yang H. Jiang T. Ma Y. Fan Z. Niu G. Yu J. Wang A. Zhang Z. 《Laser Physics》2011,21(11):1941-1944
An all-fiber high-energy nonlinear chirped-pulse amplification system with two-stage double-cladding fiber amplifiers is presented
in this paper. It generates pulses with the energy up to 10 μJ at 20 kHz repetition rate and total accumulated nonlinear phase
shift as large as 12.8π. The pulses can be compressed to 137 fs with the compensation of mismatched third-order dispersion
by self-phase modulation in the fiber amplifiers. 相似文献