利用铕(Ⅲ)-诺氟沙星-十二烷基硫酸钠的 光致发光及稀土敏化荧光法测定硫酸新霉素的浓度

室温下,在pH=7.4的氨-氯化铵缓冲溶液中,铕(Ⅲ)与诺氟沙星反应形成稳定络合物,产生稀土敏化荧光,其最佳激发、发射波长分别为λ_ex=340 nm、λ_em=612 nm,表面活性剂十二烷基硫酸钠(SDS)的加入使其荧光强度进一步增加。在该反应体系中加入适量硫酸新霉素溶液,铕(Ⅲ)与诺氟沙星络合物的激发、发射峰位置不变,但荧光强度降低,据此建立了灵敏的测定硫酸新霉素的荧光分析方法。硫酸新霉素的浓度在0.909~22.72 mg/L范围内符合线性关系。该方法的检出限为0.40 mg/L,可用于片剂及滴眼液中硫酸新霉素含量的测定,快速、简便、结果满意。6次平行测定的回收率为90.5%~102.3%,相对标准偏差为1.4%~3.5%。     

Crystal Structure of Norfloxacin Methanol Solvate: C_(16)H_(18)FN_3O_3·CH_3OH·H_2O

1 INTRODUCTION Norfloxacin (0.16 g, 5 mmol) and PdCl2 (0.02 g) in methanol solution. The brown solution was filtered Norfloxacin (H-Norf = 1-ethyl-6-fluoro-1,4-dihy- and the filtrate was stood undisturbed. Single crys- dro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic tals suitable for X-ray analysis were obtained by slow- acid), a quinolone type compound, is widely used as ly evaporating the methanol solvent at 20 ℃. an antibacterial drug which targets the bacterial type 2. 2 TGA an…     

Quantitative separation of oxytocin,norfloxacin and diclofenac sodium in milk samples using capillary electrophoresis

A simple, sensitive and rapid method has been developed for simultaneous separation and quantification of three different drugs: oxytocin (OT), norfloxacin (NOR) and diclofenac (DIC) sodium in milk samples using capillary electrophoresis (CE) with UV detection at 220 nm. Factors affecting the separation were pH, concentration of buffer and applied voltage. Separation was obtained in less than 9 min with sodium tetraborate buffer of pH 10.0 and applied voltage 30 kV. The separation was carried out from uncoated fused silica capillary with effective length of 50 cm with 75 µm i.d. The carrier electrolyte gave reproducible separation with calibration plots linear over 0.15–4.0 µg/mL for OT, 5–1000 µg/mL for NOR and 3–125 µg/mL for DIC. The lower limits of detection (LOD) were found to be 50 ng/mL for OT, and 1 µg/mL for NOR and DIC. The method was validated for the analysis of drugs in milk samples and pharmaceutical preparations with recovery of drugs within the range 96–100% with RSD 0.9–2.8%. Copyright © 2009 John Wiley & Sons, Ltd.     

氟哌酸铜配合物的合成、电子顺磁共振波谱与抗菌活性

合成了以氟哌酸药物分子和邻菲咯啉为配体的铜 ( )配合物 [Cu(NFL X) (phen) (H2 O) ]NO3· 3 H2 O(NFL X为氟哌酸 ,phen为 1,10 ' -邻菲咯啉 ) .记录了在不同状态 (固态或溶液 )、不同溶剂 (CHCl3,Py(吡啶 ) )及不同温度 (室温、77K)下的 EPR波谱 .在 [Cu(NFL X) (phen) (H2 O) ]NO3· 3 H2 O的溶液中观察到二级效应和弛豫效应 ,利用自旋哈密顿给予了满意的解释 .由低温溶液谱波谱参数计算了配合物的键参数 ,讨论了成键特性和配合物的稳定性 .利用液体稀释法测定了氟哌酸药物配体和配合物对革兰氏阳性菌和革兰氏阴性菌的体外抑制活性 ,配合物与药物配体的抗菌活性和抗菌谱相同     

几种新型锗修饰药物衍生物的合成及其抗癌活性

几种新型锗修饰药物衍生物的合成及其抗癌活性;磺酰基二苯胺;卡马西林;诺氟沙星     

含有抗菌药物诺氟沙星的金属有机羰基钼配合物(英)

Hydrothermal treatment of Mo(CO)₆, norfloxacin (H-Norf) and dilute hydroxide sodium solution in Pyrex tube leads to the formation of [Mo(H₂O)(CO)₃(H-Norf)] ·[H-Norf(H₂O) (1) which is stable toward air and moisture. Also 1 displays blue fluorescent emissions at 416～436 nm in the solid state upon irradiation by UV light. CCDC: 241564.     

Preparation of porous magnetic molecularly imprinted polymers for fast and specifically extracting trace norfloxacin residue in pork liver

Here, magnetic molecularly imprinted polymers were designed for norfloxacin via oil‐in‐water emulsifier‐free emulsion method. It was prepared by simply mixing norfloxacin, methacrylic acid‐co‐ethylene glycol dimethacrylate copolymer, and Fe₃O₄ together at room temperature. Characterized by multiple analytical tools, the particle size, pore size, pore volume, specific surface area, and saturation magnetization of the product were about 30 µm, 10–500 nm, 2.92 mL/g, 105.84 m²/g, and 3.052 emu/g, respectively. And the adsorption capacity was high at 27.04 mg/g towards norfloxacin. Combined with ultra high performance liquid chromatography, it was used to determine norfloxacin in real samples. Average recoveries were above 77.44% with relative standard deviations between 1.21 and 6.85% at three spiked levels (n = 3) for lake water and pork liver. The determination was achieved for the most complex biosample pork liver spiked with norfloxacin low to 30 ng/g, about 100 times less than the maximum residue limit regulated by Commission of the European Communities. All evidences demonstrated that the magnetic molecularly imprinted polymers can be used in practice for monitoring norfloxacin either in environmental water or meat product with high accuracy and reliability.     

Kinetic determination of the GTPase activity of Ras proteins by means of a luminescent terbium complex

Guanine nucleotide binding proteins, such as Ras proteins, play a pivotal role in maintaining the regular life cycle of cells. The involvement of Ras mutants in the progress of cancer has attracted many efforts to find detection methods for Ras activity. In this study we present a luminescent microwell plate assay for monitoring GTPase activity of Ras proteins. The luminescence intensity of the Tb–norfloxacin complex is influenced by nucleoside phosphates as well as by inorganic phosphates. Real-time kinetics of the GTPase activity of wild-type Ras and Ras mutants can be monitored online. The effect of a GTPase activating protein as well as of a downstream effector (Ras-binding domain of human Raf-1) on the GTPase activity of different Ras mutants is examined. In contrast to other methods, this assay does not require the use of radioactively labeled substrates or chromatographic separation steps. Moreover, the application of fluorescently labeled GTP substrates which often interfere with enzymatic activity can be avoided. This in vitro assay can serve as a model system for the screening of regulators affecting the GTPase activity of Ras proteins. Figure The emission of the lanthanide complex Tb(III)-norfloxacin is influenced by nucleoside phosphates as well as by inorganic phosphates. Ras proteins display a specific GTPase activity which converts protein-bound GTP to GDP and phosphate, the latter being released. The Ras activity can be monitored by a significant decrease in luminescence intensity of Tb(III)-norfloxacin owing to the strong quenching effect induced by the enzymatically hydrolyzed phosphate anions. This luminescent assay enables the monitoring of real-time kinetics of the GTPase activity of Ras proteins and Ras mutants and a fast screening of their regulators.     

A simple chromatographic method for determining norfloxacin and enoxacin in pharmacokinetic study assessing CYP1A2 inhibition

We developed a simple assay method for the determination of serum and urine norfloxacin and enoxacin using reversed‐phase high‐performance liquid chromatography and perchloric acid precipitation for sample pre‐treatment. Optimized conditions can permit detection of norfloxacin and enoxacin in the same chromatogram, so either compound can be used as an internal standard for another determinant. Supernatants of the precipitated samples were analyzed by the octadecylsilyl silica‐gel column under ambient temperature and an ultraviolet wavelength of 272 nm. A mobile phase solvent consisting of 20 mm sodium dihydrogenphosphate (pH 3.0) and acetonitrile (85:15, v/v) was pumped at a flow rate of 1.0 mL/min. The calibration curves for norfloxacin and enoxacin at a concentration of 62.5–1000 ng/mL for serum and 250–4000 ng/mL for urine were linear (r > 0.9997). The recoveries of norfloxacin and enoxacin from serum and urine were >94% with the coefficient of variations (CV) <5%. The CVs for intra‐ and inter‐day assay of norfloxacin and enoxacin were <4.2 and <5.5%, respectively. This method can be applied to the pharmacokinetic study of norfloxacin and enoxacin after repeated administration to assess changes in CYP1A2 activity in healthy subjects. Copyright © 2010 John Wiley & Sons, Ltd.     

Study on the inclusion interaction of p-sulfonatocalix[n]arenes with norfloxacin

The inclusion complexes of norfloxacin (NFX) with p-sulfonatocalix[n]arenes (SCXn) were studied. The characteristics of host–guest (HG) complexation between p-sulfonatocalix[n]arenes with NFX were investigated by fluorescence spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC). Stoichiometry and association constants (K) of the inclusion complexes were determined by the non-linear fitting method. An interesting 1:1 stochiometric of HG complexes were formed at different pH values (pH = 3.00, 6.00, 8.00) The inclusion mode of NFX with p-sulfonatocalix[n]arenes was confirmed by NMR spectroscopy.