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1.
阿霉素与血清白蛋白的作用及共存离子对反应影响的研究   总被引:53,自引:1,他引:53  
本文用荧光光度法, 分光光度法研究了抗癌药物阿霉素(Adriamycin)与微量金属离子、牛血清白蛋白(BSA)、人血清白蛋白(HSA)的相互作用, 求得药物与白蛋白的形成常数、与金属离子的结合比和形成常数, 讨论了某些金属离子对药物与白蛋白形成常数的影响。  相似文献   

2.
利用紫外-可见吸收光谱和荧光光谱,在pH=7.4的生理条件下,研究了喹诺酮类药物(依诺沙星、环丙沙星和诺氟沙星)与铜锌超氧化物歧化酶(CuZnSOD)的相互作用。喹诺酮类药物能使CuZnSOD的荧光发生猝灭,其猝灭机理为静态猝灭。通过实验计算了不同温度下喹诺酮类药物与CuZnSOD的结合常数和结合点数。依据Frster非辐射能量转移理论,得到供体与受体间的距离。根据热力学参数确定了它们之间的主要作用力类型是静电引力。进一步证实了活体动物兔子注射环丙沙星后,血液中铜锌超氧化物歧化酶活性显著降低。  相似文献   

3.
钕在小鼠体内的分布与蓄积及对孕酮分泌的影响   总被引:15,自引:2,他引:15  
应用核素示踪方法研究147Nd在小鼠体内的分布、蓄积及其对孕酮分泌的影响.一次性腹腔注射200mg@kg-1147Nd在各组织中呈不均匀分布,骨骼中表现出了高度蓄积性,且随时间的延长而增加;在眼睛、血液和大脑中均有一定的蓄积,但因排泄和体内再分配随时间而呈下降趋势;在Nd处理后血清中孕酮浓度显著低于对照组,表现了明显的抑制作用.  相似文献   

4.
本文研制了一套新型装置,该装置可用于单质硒与其他氧化态硒的分离。整套装置采用硼硅酸盐玻璃材质,由玻璃杯底座和上盖腔体两部分组成,上盖腔体顶部连接空气冷凝管。当炭化温度设为300℃,时间设为30min时,玻璃杯底座样品中的单质硒挥发并在空气冷凝管内壁冷凝,用Na2S溶液收集后经氧化还原反应得到具有荧光的硒衍生物,采用荧光光谱法定量检测硒衍生物。方法测定单质硒的线性范围为0.0~1.6μg,相关系数R2=1.0000。5份硒粉的回收率实验表明:平均回收率为97.77%~103.34%,相对标准偏差为0.95%。将上述装置应用于Z0206细菌发酵的富硒多糖样品单质硒的检测,5份样品分析结果表明,单质硒的平均含量为1923.23μg/g。  相似文献   

5.
研究了司帕沙星-铕体系的荧光光谱特性,在体系的最大激发波长(322 nm)和最大发射波长(616 nm)下,确定了铕的最佳浓度和体系的pH值.在最佳条件下,司帕沙星浓度在2~10 mg/L的范围内与体系的荧光强度呈线性关系,检测限为0.08 mg/L.对样品进行加标回收试验,回收率为96.5%~102.0%,RSD为2.5%~3.1%.利用该法测定了司帕沙星片剂中的司帕沙星含量.  相似文献   

6.
合成了两个混合配体配合物[Pd(phen)(trp)]Cl·5H_2O (1) 和 [Pd(5- NO_2phen)(trp)]Cl·5H_2O (2)(其中phen = 1,10-phenanthroline,5- NO_2phen = 5-nitro-1,10-phenanthroline,trp = L-tryptophan)。配合物对肺 腺癌细胞AGZY-83a均具有一定的杀伤活性,IC_(50)值分别为158.5 μg/mL和大于 293.0 μg/mL。荧光法测定配合物与鱼精DNA的结合常数(K)分别为6.36 * 10~6 和3.64 * 10~6。荧光光谱、紫外可见光谱和粘度法证实配合物主要以插入方式与 DNA结合。  相似文献   

7.
用荧光光度法及紫外分光光度法研究了生理条件下金属离子Ca2+、Cu2+和Zn2+对叶酸(FA)与牛血清白蛋白(BSA)相互作用的影响。结果表明:叶酸及金属离子均导致BSA的内源荧光猝灭,根据Stern-Volmer方程得到的荧光猝灭常数,可判断猝灭机制均为静态猝灭。由计算得到的热力学参数熵变ΔS和Gibbs自由能ΔG得出:推断无金属离子存在时,FA与BSA之间的作用力为静电作用力;在Ca2+的存在下,FA对BSA的作用力主要为氢键与范德华力;Cu2+和Zn2+存在下,FA对BSA的作用力主要为疏水作用力。3种金属离子的参与都使得FA与BSA结合作用的表观结合常数发生了的变化,但结合位点数仍维持在1左右。  相似文献   

8.
合成了带有叶酸靶向和荧光染料的聚合物FA-PEG-PLA和mPEG-b-P(LA-co-MHC/NIR),通过混合胶束的方法制备近红外染料胶束P(NIR)(含染料NIR6%),叶酸胶束FA-P(NIR)1(含染料NIR5.4%,叶酸LFA0.5%)和叶酸胶束FA-P(NIR)2(含染料NIR4.8%,叶酸FA0.9%);建立了H22肝癌小鼠模型,考察了高分子纳米胶束及叶酸靶向纳米胶束在H22肝癌小鼠体内分布.结果表明,高分子纳米胶束及叶酸靶向纳米胶束在小鼠体内分布都具有时间相关性,无叶酸配体的高分子纳米胶束在尾静脉注射24h后在肿瘤部位有少量聚集,大部分胶束在肝部聚集,30h内大部分已被排泄系统排出体外;含有叶酸配体的纳米胶束在尾静脉注射后6-30h内在肿瘤部位有明显的聚集,其中,FA-P(NIR)1胶束在肿瘤和肝部位的聚集相当,FA-P(NIR)2胶束在静脉注射24h后在肿瘤聚集明显高于肝部.带有叶酸配体的高分子纳米胶束相对于不带叶酸配体的纳米胶束在小鼠肿瘤部位具有明显的聚集,并且随着叶酸含量的增大,聚集效果更明显.  相似文献   

9.
高恩君  刘祁涛 《化学学报》2002,60(4):674-680
合成了两个混合配体配合物[Pd(phen)(trp)]Cl·5H_2O (1) 和 [Pd(5- NO_2phen)(trp)]Cl·5H_2O (2)(其中phen = 1,10-phenanthroline,5- NO_2phen = 5-nitro-1,10-phenanthroline,trp = L-tryptophan)。配合物对肺 腺癌细胞AGZY-83a均具有一定的杀伤活性,IC_(50)值分别为158.5 μg/mL和大于 293.0 μg/mL。荧光法测定配合物与鱼精DNA的结合常数(K)分别为6.36 * 10~6 和3.64 * 10~6。荧光光谱、紫外可见光谱和粘度法证实配合物主要以插入方式与 DNA结合。  相似文献   

10.
以海茸β-1,3/1,6-葡聚糖(DAG)为研究对象,首先经还原胺化反应在DAG还原端引入功能氨基,再将其与N-羟基丁二酰亚胺(NHS)活化的荧光染料(Cy7)偶联,获得Cy7标记的DAG分子;利用小动物活体成像技术研究了DAG在小鼠体内的分布.结果表明,DAG在小鼠体内主要分布于肺、肝和肾,具有靶向小鼠肺部和通过肾排泄的特点.该方法简便、数据可靠,为多糖和寡糖的体内分布与代谢研究提供了参考.  相似文献   

11.
Herein, an electrochemical method was developed for the determination of ciprofloxacin based on the enhancement effect of cetyltrimethylammonium bromide (CTAB). In pH 7.0 phosphate buffer, a poorly-defined oxidation peak is observed at carbon paste electrode (CPE) for ciprofloxacin. However, the oxidation peak current remarkably increases in the presence of low concentration of CTAB, suggesting that CTAB exhibits obvious enhancement effect to the determination of ciprofloxacin. All the experimental parameters, such as supporting electrolyte, pH value, concentration of CTAB, and accumulation time, were optimized for ciprofloxacin analysis. This new method possesses high sensitivity (detection limit is 5.0 × 10−8 mol l−1), wide linearity (1.0 × 10−7−2.0 × 10−5 mol l−1), rapid response, low cost and simplicity. Finally, this method was successfully employed to detect ciprofloxacin in drugs. The text was submitted by the authors in English.  相似文献   

12.
利用荧光光谱法研究了环丙沙星与母体β-环糊精(β-CD)及其2种修饰衍生物羟丙基-β-环糊精(Hp-β-CD)、甲基-β-环糊精(Me-β-CD)形成的超分子体系,同时测定了3种超分子体系的猝灭常数和热力学参数.结果表明:环丙沙星与3种环糊精之间常温下均形成稳定的包合物;环丙沙星与3种环糊精包结过程中△G<0和△H<0,这说明环丙沙星与3种环糊精的包结能够自发进行而形成超分子体系,且反应为放热过程.通过对3种环糊精与环丙沙星的热力学数包结能力进行了比较,初步探讨了作用机理和影响包结能力大小的可能因素.  相似文献   

13.
The proposed research, presents the synthesis, characterization, and photocatalytic accomplishment of ZnO nanoplate (ZnOs) modified with activated carbon derived from Konar bark. The obtained nanocomposite (photocatalyst) was characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD), Raman spectroscopy, X‐ray photoelectron spectroscopy (XPS), and Brunauer–Emmett–Teller (BET). First, the ZnO photocatalyst and activated carbon (AC) were prepared separately; then, the ZnO photocatalyst was modified with activated carbon. Various parameters namely pH, degradation time, and photocatalyst dose were optimized and studied in multivariate method by design expert7 software. The synergic efficiency of ZnO‐AC (adsorbent/photocatalyst) exhibited a good rate of ciprofloxacin (CIP) removal under visible irradiation. In addition, first pseudo order kinetic and isotherms equations were calculated. Moreover, the identification of degradation products was performed by ultra performance liquid chromatography‐tandem mass spectrometer (UPLC‐MS/MS). It is for the first time that a ZnO photocatalyst modified with activated carbon (ZnO‐AC) applied for CIP degradation.  相似文献   

14.
An efficient, selective and cost‐effective liquid chromatographic assay was developed and validated for the simultaneous quantification of ciprofloxacin and rosuvastatin in Active Pharmaceutical Ingredients (API), pharmaceutical formulations and in human serum. The chromatographic system consisted of mobile phase methanol–water, 90:10 v/v at pH 3.0 adjusted with o‐phosphoric acid, pumped at 1.0 mL/min through a prepacked Purospher Star C18 (5 µm, 25 × 0.46 cm) column and effluent was monitored at the isosbestic point (255 nm) as well as at the λmax of individual drugs (243 and 271 nm). The method was validated over a linear concentration range of 0.25–15 µg/mL for ciprofloxacin and 0.33–20 µg/mL for rosuvastatin (r2 ≥ 0.999). The ranges of reliable response (limits of detection and quantitation) for ciprofloxacin were 3–15 and 9–45 ng/mL and 17–29 and 52–88 ng/mL, respectively, for rosuvastatin in all API, pharmaceutical formulations and human serum. Analytical recovery from human serum was >98% and relative standard deviation (RSD) was <2. The accuracies were 97.13–102.55 and 97.41–101.31% and precisions in RSD were 0.04–1.90 and 0.02–1.23% for ciprofloxacin and rosuvastatin, respectively. No matrix interferences, ion suppression/enhancement and carry‐over were detected. The total assay run time was less than 5 min. In another study, for optimum performance the detector was programmed for multiwavelength scanning at the absorption maxima of each component. Consequently, the linearity range was improved and limit of detection and quantitation values were down to 1–4 and 4–12 ng/mL for ciprofloxacin and 3–5 and 9–15 ng/mL for rosuvastatin, respectively. The validation parameters fitted ICH guidelines through the isosbestic and individual λmax approach. The small sample volume and simplicity of preparation make this method suitable for use in human serum samples, pharmaceutical formulations, quality control, drug–drug interaction studies, clinical laboratories, drug research centers and forensic medical centers. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

15.
Cinnamaldehyde (CA), an active ingredient isolated from the traditional Chinese medicine Cortex Cinnamomi, has a wide range of bioactivities. To clarify the distribution characteristics of CA, a selective and sensitive method utilizing gas chromatography–mass spetrometry was initially developed for simultaneously determining the concentration of CA and its metabolite cinnamyl alcohol in rat tissues. Selected ion masses of m/z 131, 105 and 92 were chosen, and separation of the analytes was performed on a DB‐5 ms (30 m × 0.25 mm, 0.25 µm, thickness) capillary column by gas chromatography–mass spectrometry. The calibration curves demonstrated good linearity and reproducibility over the range of 20–2000 and 20–4000 ng/mL for various tissue samples. Recoveries ranged from 86.8 to 107.5%, while intra‐ and interday relative standard deviations were all <11.3%. The analysis method was successfully applied in tissue distribution studies for CA and cinnamyl alcohol. As CA and cinnamyl alcohol may inter‐convert to one another, simultaneous determination of both analytes provides a comparative and accurate data for tissue study. The concentrations of CA and cinnamyl alcohol remaining in spleen were the highest among the main organs, including heart, liver, spleen, lung, kidney and brain. In addition, there was no long‐term accumulation of CA in rat tissues. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

16.
A set of new aluminium complexes of norfloxacin (NOR) and ciprofloxacin (CIP) that show an improvement in their pharmaceutical properties were studied using solution and solid-state nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy. The complexes synthesized with two different methods were compared. One of these methods will allow formulation of the compounds at production scale. High-resolution (13)C spectra were obtained with the cross-polarization and magic angle spinning (CP-MAS) experiment. These spectra were assigned by comparing them with the solution data of the pure drug and by using a quaternary carbon edition technique. The carbon relaxation times in the rotating frame, T(1rhoC), were measured for all the complexes. A two-exponential decay evidences that the complexes are nonhomogeneous. The short T(1rhoC) values are in the range 320-1100 micros and the long values in the range 1.8-7 ms. (27)Al MAS NMR spectra revealed an octahedral coordination between the aluminium ion and oxygens of the pure drug, supporting a 3:1 ligand:metal stoichiometry in both CIP and NOR complexes. The stretching and deformation modes of carboxylic acid and carboxylate and keto groups were analyzed by IR. This technique shows that the same modes are present in the aluminium complexes obtained by the two methods and that the coordination of the fluoroquinolone to aluminium occurs through the 4-keto and 3-carboxylic groups.  相似文献   

17.
A simple and fast liquid chromatographic method coupled with fluorescence detection (LC‐FD) is reported, for the first time, for the simultaneous quantification of norfloxacin (NOR), ciprofloxacin (CIP) and lomefloxacin (LOM) in human plasma, using levofloxacin as internal standard (IS). Sample preparation consists of a single‐step precipitation of plasma proteins followed by vortex‐mixing and centrifugation. Chromatographic separation was achieved within 7 min on a reversed‐phase C18 column with a mobile phase consisting of 0.1% aqueous formic acid (pH = 3.0, triethylamine)–methanol (82:18, v/v) pumped isocratically at 1.2 mL/min. The detector was set at excitation/emission wavelengths of 278/450 nm. Calibration curves were linear (r2 ≥ 0.994) in the range of 0.02–5.0 µg/mL, and the limit of quantification was established at 0.02 µg/mL for all analytes (NOR, CIP and LOM). The overall precision did not exceed 8.19% and accuracy was within ±10.91%. NOR, CIP and LOM were extracted from human plasma with an overall mean recovery ranged from 90.1 to 111.5%. No interferences were observed at the retention times of the analytes and IS. This novel LC‐FD method enables the reliable determination of NOR, CIP and LOM in a single chromatographic run, which may be suitable to support human pharmacokinetic‐based studies with those antimicrobial agents. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

18.
Curcumin (CUR) is the major active component of turmeric and plays an important role in the prevention and treatment of many chronic diseases such as respiratory and neurodegenerative disease. In the present work, a rapid and simple LC–MS/MS method was developed to investigate the pharmacokinetics and tissue distribution of CUR and its metabolites in mice after intravenous administration of CUR (20 mg/kg). The results showed that the values of AUC0–∞ were 107.0 ± 18.3, 6.0 ± 1.2 and 12.0 ± 4.0 (mg/L) min, and those for t1/2z were 32.4 ± 10.8, 6.4 ± 2.4 and 5.6 ± 1.8 min for CUR, dihydrocurcumin (DHC) and tetrahydrocurcumin (THC) in plasma, respectively. CUR and THC could be detected in liver while CUR and DHC were detected in kidney. Only CUR was detected in brain. These findings indicated that THC was the main metabolite of CUR in plasma. The exposure of CUR in plasma was 6‐fold greater than that in liver, kidney and brain.  相似文献   

19.
术后粘连是腹腔、妇科、矫形外科及心脏手术之后遇到的一个普遍的问题。大约80-90%的腹腔粘连直接起因于先前的手术[1]。这些粘连可以通过二次手术治疗,但这不仅耗时、花费高,而且增加了再次粘连、疤痕组织形成和细菌感染的潜在性。粘连的预防能减少医疗费用及治疗的复杂程度。  相似文献   

20.
高效液相色谱法同时测定水体中的环丙沙星和氟甲喹   总被引:1,自引:0,他引:1  
李璐  刘菲  陈鸿汉  秦晓鹏 《色谱》2013,31(6):567-571
为了满足实验室测试和野外测试需要,也为其他学者研究不同抗生素之间的相互作用提供相关的资料,本研究选用环丙沙星(CIP)和氟甲喹(FLU)作为代表,建立了一种简单、稳定、易普及的高效液相色谱法用于同时快速测定水体中两种氟喹诺酮类抗生素的含量,并讨论了不同流动相及其比例和水样中几种常见阴、阳离子(Ca2+、Mg2+、Fe3+、Al3+、SO42-和HCO3-)对抗生素测定的影响。结果表明:三乙胺对改善柱效有明显效果;低浓度离子对测试影响不大,但Fe3+和Al3+可能与固定相的表面羟基或测试组分发生配合作用,造成基线不稳。实验结果对其他研究者对于流动相的选择与优化具有借鉴意义。  相似文献   

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