漫反射FT-IR法测定阿奇霉素片剂中阿奇霉素的含量

采用红外温反射定量分析技术，测定了阿奇霉素片剂中阿奇霉素的含量。在红外光谱中，吸光度与阿奇霉素的浓度成良好的线性关系，平均回回收率为99.2%,RSD为1.7%。可用于阿奇霉素片剂中阿奇霉素的含量测定。     

阿奇霉素片及胶囊剂溶出度考察

采用硫酸显色法对两家药厂生产的阿奇霉素片及胶囊剂进行了溶出度考察。结果表明，阿奇霉素在10－100μg/mL范围内线性关系良好，平均 回收率为99．83％（n=6)。阿奇霉素片及胶囊剂在45min时的溶出量均不低于标示量的80％。而两厂产品体外溶出度结果均达到要求。     

阿奇霉素与百里香酚蓝的荷移反应及其在药物测定中的应用

基于阿奇霉素与百里香酚蓝在无水乙醇介质中可以发生荷移反应,建立了测定阿奇霉素的新方法.在无水乙醇溶剂中,阿奇霉素与百里香酚蓝发生荷移反应,其荷移络合物在550 nm处有最大吸收峰.由吸光度测定阿奇霉素的含量.表观摩尔吸光系数ε=8.5×103 L·mol-1·cm-1,络合物组成比为1:2.稳定常数为1.0×1010,阿奇霉素质量浓度在2.52～21.0μg/mL内与吸光度呈良好的线性关系,线性回归方程为A=-0.02242+0..167ρ(μg/mL),线性相关系数R=0.9994,检出限(3ρ/k)为2.52μg/mL,相对标准偏差为1.4%.     

Ru(bpy)_3~(2+)体系电化学发光法测定阿奇霉素的研究

实验发现,阿奇霉素对联吡啶钌的电致化学发光(ECL)具有显著的增强作用。据此,建立了以金电极为工作电极的测定阿奇霉素ECL分析新方法。采用了循环伏安(CV)和ECL法,研究了阿奇霉素对联吡啶钌体系的电化学行为和ECL行为的增强作用。结果表明,在最佳条件下,阿奇霉素浓度在2.0×10-4～4.0×10-7 mol/L范围内与相对发光强度呈线性关系,其线性回归方程为I计数=22.848×106 C+221.8(r=0.9981,n=12)。检出限为3.00×10-9 mol/L(S/N=3)。连续平行测定1.0×10-5 mol/L的阿奇霉素标品溶液10次,发光强度值的相对标准偏差(RSD)为2.09%。对样品进行回收率试验,回收率在95.0%～102.0%之间,RSD为2.40%(n=5)。该方法具有较高的选择性和灵敏度,样品处理简单快速,用于药物中阿奇霉素的测定,结果满意。     

阿奇霉素在多壁碳纳米管修饰电极上的电化学行为及其测定

运用循环伏安法与线性扫描伏安法研究了阿奇霉素在多壁碳纳米管修饰玻碳电极上的电化学行为,建立了一种直接测定阿奇霉素的电化学分析方法。结果表明,与裸玻碳电极相比,多壁碳纳米管修饰电极能显著提高阿奇霉素的氧化峰电流,阿奇霉素的电极过程完全不可逆,存在典型的吸附特性。在优化的实验条件下,氧化峰电流与阿奇霉素浓度在3.0×10-7～2.5×10-5 mol/L和2.5×10-5～5.0×10-4 mol/L范围内呈现良好的线性关系,检出限为1.0×10-7 mol/L。     

反相高效液相色谱法测定阿奇霉素及其相关化合物

建立了利用简单流动相组成测定阿奇霉素及其相关化合物的反相高效液相色谱法,色谱柱为InertsilODS 3(150mm×4. 6mm, 5μm),流动相为乙腈水(90∶10,V/V),流速0. 8mL/min,柱温30℃;紫外检测波长为205nm。能够明确地分辨阿奇霉素粗品中5种物质:红霉素6, 9亚胺醚、红霉素9, 11亚胺醚、阿奇霉素前体、甲基化硼酸酯和阿奇霉素。该方法简便快捷,线性关系良好,结果准确可靠,对阿奇霉素合成工艺优化和成品的质量检测均具有指导作用。     

高效液相色谱电化学检测法测定阿奇霉素及相关组分

提出了用高效液相色谱电化学检测法同时测定阿奇霉素颗粒中阿奇霉素(AZMC)及相关组分(即脱糖氧胺阿奇霉素、阿奇霉素A及N-去甲基阿奇霉素)含量的方法.采用Thermo C18柱(150 mm×4.6 mm,5μm)作固定相分离上述4组分.以20 mmol·L-1磷酸二氢钾(用1 mol·L-1氢氧化钾溶液调pH为7.37)-甲醇(47+53)为流动相,流量为1.0 mL·min-1,电化学检测电位为1.05 V,柱温为35℃.阿奇霉素及相关组分的峰面积值与相应浓度之间的线性范围依次为37.06～593.00,2.63～84.00,9.20～294.50,6.69～107.00 mg·L-1,检出限(3S/N)分别为9.28,1.32,4.60,3.35 mg·L-1.用标准加入法作回收试验,测得平均回收率分别为99.9%,100.6%,99.9%,99.8%.     

阿奇霉素注射剂用于抗感染的疗效和不良反应的分析

为更合理使用阿奇霉素注射剂，搜集整理了近几年来国内有关阿奇霉素注射剂用于抗各种病原体感染的临床文献报道，从这些资料中选出具有普遍性和代表性的有关阿奇霉素注射剂用于儿童、成人抗体内各种病原体感染时产生的疗效和不良反应，并与同类药物红霉素注射剂作相应对照试验的原始临床资料进行了分析、比较。结果表明，阿奇霉素抗感染的疗效和安全性等方面均明显优于红霉素，合理地使用该药可尽量减少其不良反应的发生。     

阿奇霉素与茜素的电荷转移反应及其测定

建立了一种快速测定阿奇霉素的荷移分光光度法。阿奇霉素与茜素在乙醇介质中发生电荷转移反应 ,电荷转移络合物在 5 4 6nm处有最大吸收 ,表观摩尔吸光系数为 5 .79× 10 3 L·mol-1·cm-1;该络合物的组成是 1∶1;稳定常数为 4 .8× 10 3 ;药物浓度在 5～ 12 0mg/L范围内服从比耳定律。利用本法测定了阿奇霉素制剂中有效成分的含量 ,并与文献法进行比较 ,二者结果基本吻合。     

QuEChERS-高效液相色谱-串联质谱法测定动物源食品中阿奇霉素残留

建立了QuEChERS前处理,液相色谱-串联质谱测定动物源食品中阿奇霉素残留的快速分析方法。样品以乙腈提取,N-丙基乙二胺(PSA)净化,采用Zorbax Eclipse Plus C18柱(3.0 mm×100 mm,1.8μm)分离,以乙腈-0.1%甲酸溶液为流动相,梯度洗脱。阿奇霉素采用电喷雾正离子源(ESI+)、多重反应监测(MRM)模式检测,以保留时间和特征离子对(母离子和2个碎片离子)信息比较进行定性分析和定量分析。阿奇霉素在1.0~50.0 ng/m L范围内线性相关系数均大于0.995;在6种基质(鸡肉、牛肉、猪肉、猪肝、鲤鱼、牛奶)中方法的检出限(S/N=3)均为0.3μg/kg,定量限(S/N=10)均为1.0μg/kg;3个加标水平(1,2,10μg/kg)下,回收率为81.4%~103.8%,相对标准偏差为3.6%~8.9%。     

Sensitive liquid chromatography/mass spectrometry assay for the quantification of azithromycin in human plasma

A simple, rapid, sensitive and specific liquid chromatography/electrospray ionization mass spectrometry method was developed and validated to quantify azithromycin in human plasma, using erythromycin as the internal standard (IS). A simple sample preparation method of protein precipitation with methanol was employed. Methanol, acetonitrile and water (12:30:58, v/v/v) were used as the isocratic mobile phase, with 0.1% formic acid and 0.1% ammonium acetate in water. Selected ion monitoring was specific for azithromycin and erythromycin. The assay was linear over the concentration range 4.69-600 ng/mL. The correlation coefficients for the calibration curves ranged from 0.9994 to 0.9998. The intra- and inter-day precisions, calculated from quality control samples, were less than 8.24%. The method was employed in a pharmacokinetic study after oral administration of 500 mg azithromycin dispersible tablet to 20 healthy volunteers.     

液相色谱-串联质谱法测定育肥猪配合饲料中的阿奇霉素

通过对提取溶剂、净化方法及色谱-质谱条件的优化,建立了配合饲料中阿奇霉素(AZM)的液相色谱-串联质谱测定方法。样品经乙腈超声波提取,MCX固相萃取柱净化,BDS Hypersil C_(18)(2.4μm,100 mm×2.1 mm)色谱柱分离,以甲醇-0.05 mol/L乙酸铵水溶液为流动相梯度洗脱,正离子模式电离,多反应监测模式检测,同位素内标法定量。在优化条件下,AZM在1~250μg/L范围内线性关系良好,相关系数(r~2)为0.999 1,检出限(S/N≥3)为2.8μg/kg,定量下限(S/N≥10)为8.4μg/kg;在0.5,1,5,10 mg/kg加标水平下,回收率为87.0%~106.6%,批内相对标准偏差为0.58%~5.4%,批间相对标准偏差为3.1%~5.4%。该方法准确、灵敏,选择性强,基质干扰小,可用于配合饲料中AZM的测定。     

New Spectrophotometric Method for Azithromycin Determination

Abstract

Azithromycin (AZT), an antibiotic belonging to the family of macrolides, can be analyzed by a new spectrophotometric method based on the formation of an ion pair between this drug and an inorganic complex of (Mo(V)–thiocyanate) followed by its extraction with dichloroethane. This ion‐association complex shows an orange color and exhibits a maximum absorbance at 469 nm. The experimental conditions of the reaction were studied and optimized. The calibration graph was linear (r=0.9996) over the range 10^?6 M–10^?5 M of AZT. This simple and validated method has been successfully applied to the determination of azithromycin in pharmaceutical formulations with a mean relative standard deviation of 1.07% and mean recovery of 99.66%. The common excipients present in azithromycin formulations did not interfere in its determination. This new spectophotometric method has been applied successfully to illustrate the dissolution profiles of original tablets and generic compounds; hence, it could be employed in routine quality control of azithromycin in pharmaceutical dosage forms.     

Catalytic Effect of Cobalt and Iron Complexes Incorporating Bis(2-aldiminoethyl)amine Ligands on Ethylene Oligomerization

IntroductionThe finding of a new promising family ofFe( ) - and Co( ) - based bis( imino) pyridyl cata-lysts for ethylene polymerization and oligomeriza-tion,discovered by Brookhart,Gibson andcoworkers[1— 3 ] ,has intrigued us into researchingthe preparation,the structure and the chemistry ofiron and cobalt complexes incorporating N,N ,N -tridentate ligands.The spectacular enhancement ofthe reactivity of iron and cobalt complexes towardsZiegler- Natta olefin polymerization has been re-po…     

Atmospheric chemistry of propionaldehyde: kinetics and mechanisms of reactions with OH radicals and Cl atoms, UV spectrum, and self-reaction kinetics of CH3CH2C(O)O2 radicals at 298 K

The kinetics and mechanism of the reactions of Cl atoms and OH radicals with CH3CH2CHO were investigated at room temperature using two complementary techniques: flash photolysis/UV absorption and continuous photolysis/FTIR smog chamber. Reaction with Cl atoms proceeds predominantly by abstraction of the aldehydic hydrogen atom to form acyl radicals. FTIR measurements indicated that the acyl forming channel accounts for (88 +/- 5)%, while UV measurements indicated that the acyl forming channel accounts for (88 +/- 3)%. Relative rate methods were used to measure: k(Cl + CH3CH2CHO) = (1.20 +/- 0.23) x 10(-10); k(OH + CH3CH2CHO) = (1.82 +/- 0.23) x 10(-11); and k(Cl + CH3CH2C(O)Cl) = (1.64 +/- 0.22) x 10(-12) cm3 molecule(-1) s(-1). The UV spectrum of CH3CH2C(O)O2, rate constant for self-reaction, and rate constant for cross-reaction with CH3CH2O2 were determined: sigma(207 nm) = (6.71 +/- 0.19) x 10(-18) cm2 molecule(-1), k(CH3CH2C(O)O2 + CH3CH2C(O)O2) = (1.68 +/- 0.08) x 10(-11), and k(CH3CH2C(O)O2 + CH3CH2O2) = (1.20 +/- 0.06) x 10(-11) cm3 molecule(-1) s(-1), where quoted uncertainties only represent 2sigma statistical errors. The infrared spectrum of C2H5C(O)O2NO2 was recorded, and products of the Cl-initiated oxidation of CH3CH2CHO in the presence of O2 with, and without, NO(x) were identified. Results are discussed with respect to the atmospheric chemistry of propionaldehyde.     

Formation and chemical reactivities of a new type of double-butterfly [[Fe2(mu-CO)(CO)6]2(mu-SZS-mu)]2-: synthetic and structural studies on novel linear and macrocyclic butterfly Fe/E (E=S,Se) cluster complexes

A new type of double-butterfly [[Fe(2)(mu-CO)(CO)(6)](2)(mu-SZS-mu)](2-) (3), a dianion that has two mu-CO ligands, has been synthesized from dithiol HSZSH (Z=(CH(2))(4), CH(2)(CH(2)OCH(2))(1-3)CH(2)), [Fe(3)(CO)(12)], and Et(3)N in a molar ratio of 1:2:2 at room temperature. Interestingly, the in situ reactions of dianions 3 with various electrophiles affords a series of novel linear and macrocyclic butterfly Fe/E (E=S, Se) cluster complexes. For instance, while reactions of 3 with PhC(O)Cl and Ph(2)PCl give linear clusters [[Fe(2)(mu-PhCO)(CO)(6)](2)(mu-SZS-mu)] (4 a,b: Z=CH(2)(CH(2)OCH(2))(2,3)CH(2)) and [[Fe(2)(mu-Ph(2)P)(CO)(6)](2)(mu-SZS-mu)] (5 a,b: Z=CH(2)(CH(2)OCH(2))(2,3)CH(2)), reactions with CS(2) followed by treatment with monohalides RX or dihalides X-Y-X give both linear clusters [[Fe(2)(mu-RCS(2))(CO)(6)](2)(mu-SZS-mu)] (6 a-e: Z=CH(2)(CH(2)OCH(2))(1,2)CH(2); R=Me, PhCH(2), FeCp(CO)(2)) and macrocyclic clusters [[Fe(2)(CO)(6)](2)(mu-SZS-mu)(mu-CS(2)YCS(2)-mu)] (7 a-e: Z=(CH(2))(4), CH(2)(CH(2)OCH(2))(1-3)CH(2); Y=(CH(2))(2-4), 1,3,5-Me(CH(2))(2)C(6)H(3), 1,4-(CH(2))(2)C(6)H(4)). In addition, reactions of dianions 3 with [Fe(2)(mu-S(2))(CO)(6)] followed by treatment with RX or X-Y-X give linear clusters [[[Fe(2)(CO)(6)](2)(mu-RS)(mu(4)-S)](2)(mu-SZS-mu)] (8 a-c: Z=CH(2)(CH(2)OCH(2))(1,2)CH(2); R=Me, PhCH(2)) and macrocyclic clusters [[[Fe(2)(CO)(6)](2)(mu(4)-S)](2)(mu-SYS-mu)(mu-SZS-mu)] (9 a,b: Z=CH(2)(CH(2)OCH(2))(2,3)CH(2); Y=(CH(2))(4)), and reactions with SeCl(2) afford macrocycles [[Fe(2)(CO)(6)](2)(mu(4)-Se)(mu-SZS-mu)] (10 d: Z=CH(2)(CH(2)OCH(2))(3)CH(2)) and [[[Fe(2)(CO)(6)](2)(mu(4)-Se)](2)(mu-SZS-mu)(2)] (11 a-d: Z=(CH(2))(4), CH(2)(CH(2)OCH(2))(1-3)CH(2)). Production pathways have been suggested; these involve initial nucleophilic attacks by the Fe-centered dianions 3 at the corresponding electrophiles. All the products are new and have been characterized by combustion analysis and spectroscopy, and by X-ray diffraction techniques for 6 c, 7 d, 9 b, 10 d, and 11 c in particular. X-ray diffraction analyses revealed that the double-butterfly cluster core Fe(4)S(2)Se in 10 d is severely distorted in comparison to that in 11 c. In view of the Z chains in 10 a-c being shorter than the chain in 10 d, the double cluster core Fe(4)S(2)Se in 10 a-c would be expected to be even more severely distorted, a possible reason for why 10 a-c could not be formed.     

Pnictides as symmetrically bridging ligands in novel neutral complexes

The reaction of [LWCl] (3) [L = N(CH2CH2NiPr)3] with LiE(SiMe3)2 (E = P, As, Sb) yields the novel, neutral pnictido-bridged complexes [LW = E = WL] (5-7). By following the reaction, which starts from the LiP-(SiMe3)2 derivative, by 31P NMR spectroscopy, the formation of an intermediate with a terminal pnictido ligand can be ruled out. The paramagnetic complexes 5-7 are comprehensively spectroscopically characterised. The X-ray structure analysis of the heterocumulenes 5-7 reveals a linear structure in which the two W-"tren" units bind to the central pnictido atom in a staggered conformation ["tren" = tren-based ligand; tren = tris(2-aminoethyl)-amine. When N2 is used as the inert gas in the synthesis of the starting material [N(CH2CH2NNp)3WCl] [Np = CH2C-(CH3)3], the complex [[N(CH2CH2NNp)3]W2(mu, eta 1: eta 1-N2)] (4) is formed as a side product. Complex 4 possesses a hydrazido(4-) (N2(4-)) ligand connected by two tungsten-"tren" moieties.     

A liquid chromatography–mass spectrometric method for the quantification of azithromycin in human plasma

A liquid chromatographic mass spectrometric assay for the quantification of azithromycin in human plasma was developed. Azithromycin and imipramine (as internal standard, IS) were extracted from 0.5 mL human plasma using extraction with diethyl ether under alkaline conditions. Chromatographic separation of drug and IS was performed using a C₁₈ column at room temperature. A mobile phase consisting of methanol, water, ammonium hydroxide and ammonium acetate was pumped at 0.2 mL/min. The mass spectrometer was operated in positive ion mode and selected ion recording acquisition mode. The ions utilized for quantification of azithromycin and IS were m/z 749.6 (M + H) ⁺ and m/z 591.4 (fragment) for azithromycin, and 281.1 m/z for internal standard; retention times were 6.9 and 3.4 min, respectively. The calibration curves were linear (r² > 0.999) in the concentration ranges of 10–1000 ng/mL. The mean absolute recoveries for 50 and 500 ng/mL azithromycin and 1 µg/ mL IS were >75%. The percentage coefficient of variation and mean error were <11%. Based on validation data, the lower limit of quantification was 10 ng/mL. The present method was successfully applied to determine azithromycin pharmacokinetic parameters in two obese volunteers. The assay had applicability for use in pharmacokinetic studies. Copyright © 2013 John Wiley & Sons, Ltd.     

Determination of total mercury and methylmercury in human hair by graphite-furnace atomic absorption spectrophotometry using 2,3-dimercaptopropane-1-sulfonate as a complexing agent.

For the determination of total mercury in hair, an amount (25.0 mg) of hair sample was digested with conc. HNO3 (400 microl) at 90 degrees C for 10 min in a 7-ml teflon microreaction vessel. After digestion, the pH of the acidic hair mixture was adjusted to 5.0-6.0 by NaOH and was then passed through a clean-up Sep-Pak C18 cartridge. To the eluate, 2,3-dimercaptopropane-1-sulfonate (DMPS) and sodium acetate buffer (pH = 6.0) were added to form a mercury-DMPS complex. This complex was preconcentrated on two Sep-Pak C18 cartridges in series, and each cartridge was eluted with methanol and adjusted to 2.00 ml. A portion (50 microl) was introduced into a graphite cuvette and then atomized according to a temperature program. The method detection limit (MDL, 3sigma) was 0.064 (microg g(-1)); the calibration graph was linear up to 7.52 microg g(-1). Good accuracies were obtained when testing two human hair certified reference materials (GBW 09101 and BCR-397). Six real samples were analyzed, and the recoveries were 95.8 - 98.2% with a relative standard deviation (RSD, n = 3) < 2.1%. For the determination of methylmercury (CH3Hg+), 25.0 mg of hair sample was extracted with 2.0 mol dm(-3) HCl (1.0 ml) by ultrasonicating for 1 h. The supernatant solution was used for CH3Hg+ analysis and the hair residue was used for the analysis of inorganic mercury (Hg2+). The MDL of CH3Hg+ was 0.068 microg g(-1); the calibration graph was linear up to 6.00 microg g(-1). Six real samples were analyzed, and the recoveries were 96.0-99.2% with RSD (n = 3) < 2.3%. The sum of the concentrations of CH3Hg+ and Hg2+ was very close to that of the total mercury measured with a relative error within 3.6%. The proposed method can be accurately applied to the measurement of CH3Hg+, Hg2+, and total mercury in hair samples.     

通过Michaelis-Arbuzov重排合成新型

α-溴代-叔丁基甲基酮和3-取代2,2-二甲基环丙烷羧基氯化物与亚磷酸酯反应,生成膦酸酯,并描述了膦酸酯的溴化反应.