快速灵敏的LC-MS/MS法测定人血浆中阿莫西林并应用于两种制剂的一致性评价

目的: 建立快速灵敏的LC-MS/MS法测定人血浆中阿莫西林浓度，并用于两种阿莫西林胶囊的一致性评价。方法: 采用岛津公司LCMS-8060型LC-MS/MS仪，以MRM模式测定阿莫西林（m/z 366.00/114.00）的浓度，d4-阿莫西林作内标（m/z 370.10/114.05），离子源为ESI源。色谱柱选用Waters ACQUITY BEH C18（2.1×50 mm，1.7 μm），梯度洗脱。血浆样本加入内标，经甲醇沉淀蛋白后取上清液进样检测。结果: 所建方法经验证，其线性、准确度、精密度、最低定量限、提取回收率、特异性、基质效应、稳定性等各项指标均符合CFDA的指导原则及最新核查标准要求，并较文献报道中的方法有处理简单、灵敏度高、色谱峰形好的优点。结论: 所建方法快速、灵敏，适用于人血浆中阿莫西林浓度的检测。用于一致性评价的样本实测，两种制剂生物等效。     

太赫兹时域光谱技术用于药品检测

为研究太赫兹光谱技术用于药品检测的可行性,利用自行搭建的时间扫描太赫兹时域光谱系统对3种不同厂家生产的阿莫西林胶囊进行了测试。测试结果表明,尽管与文献上在氮气环境中获得的结果存在一定差异,但3种样品在太赫兹波段仍然显示出了明显的特征吸收,且不同厂家的药品在吸收峰位置、强度以及折射率谱等方面均有所差别。研究结果证实了太赫兹光谱技术在青霉素类药品的质量监控及在线检测等方面具有广阔的应用前景。     

阿莫西林舒巴坦匹酯分散片处方工艺研究

采用四因素三水平正交试验,以崩解时间为评价指标,筛选阿莫西林舒巴坦匹酯分散片的处方,并对其进行稳定性考察,结果显示其稳定性良好,处方工艺合理。     

牛奶中阿莫西林含量表面增强拉曼光谱检测方法的建立

以香水百合花瓣绿色合成的银溶胶为表面增强拉曼散射（SERS）活性基底，建立了牛奶中阿莫西林含量的SERS检测方法。对SERS检测条件进行了优化，考察了银溶胶浓度、银溶胶与阿莫西林溶液的体积比和氯化钠溶液的添加与否对SERS检测的影响。试验结果表明：当银溶胶浓度为106.04 μg/mL、银溶胶与阿莫西林溶液的体积比为41且不添加氯化钠的条件下，获得的SERS信号最强。在该条件下，阿莫西林标准溶液的浓度与1 055 cm^-1 处拉曼特征峰的SERS信号强度在1～1 000 μg/mL 范围内有良好的线性关系，方法的最低检出浓度可达到1 μg/mL。3份加标牛奶中阿莫西林的加标回收率为84.51%～93.62%，相对标准偏差（RSD）为5.16%。该方法简单方便，可实现牛奶中一定浓度阿莫西林的检测。     

Prevalence and antimicrobial resistance of Salmonella isolated from an integrated broiler chicken supply chain in Qingdao,China

The present study analyzed the prevalence and antimicrobial resistance of Salmonella along an integrated broiler chicken supply chain. A total of 172 Salmonella isolates were recovered from 1148 samples collected from four sample sources (breeder farms, broiler farms, abattoir, and retail markets), representing nine production stages. These Salmonella isolates were examined for antimicrobial susceptibility to 12 different antimicrobial agents using a disk diffusion assay. Among them, 168 were identified as six different serotypes of Salmonella enterica. The predominant serotype was S. Enteritidis (n = 116), followed by S. Infantis (n = 18), S. Gueuletapee (n = 16), S. Derby (n = 12), S. Meleagridis (n = 4), and S. London (n = 2). The remaining four isolates were serogroup-untypeable. A majority of the 172 isolates (96.51%) was resistant to one or more antibiotics and 61.05% of the Salmonella isolates showed a multidrug resistance phenotype. Statistical analysis indicated the one risk product stage for Salmonella contamination occurred in the sample source at the abattoir, specifically the stage of Carcasses after chilling. The majority of S. Enteritidis isolates shared the same pulsed-field gel electrophoresis (PFGE) cluster, suggesting that the S. Enteritidis strain might spread along the broiler chicken supply chain. The prevalence and antimicrobial resistance of Salmonella in different production stages suggest the importance of controlling Salmonella in the broiler chicken supply chain for public health, underlying the need for improved measures of reducing carcass contamination in abattoirs and the appropriate use of antimicrobials in broiler flocks.     

Differential patterns of antimicrobial resistance in population subsets of Escherichia coli isolated from waste- and surface waters

The species Escherichia coli comprises different subgroups with distinct phylogeny, physiology and ecology and, thus, presumably, with different roles in antimicrobial resistance dissemination. E. coli strains isolated from raw and treated municipal wastewater and from urban water streams were characterized in terms of phylogenetic groups, antimicrobial resistance patterns and the presence of class 1 and class 2 integrons. Our main objective was to investigate the contribution of the different phylo-groups in antimicrobial resistance dissemination in urban waters. Groups A and B1 were predominant in all types of water, evidencing, respectively, the lowest and the highest resistance prevalence. Municipal wastewater treatment was accompanied by significant increases of ciprofloxacin and streptomycin resistance (p < 0.01). Antimicrobial resistance prevalence differed significantly between the different phylo-groups and within the same group, mainly in group A. Such differences contributed to explain the higher ciprofloxacin and streptomycin resistance rates observed in treated effluent in comparison with the raw wastewater. We conclude that the dynamics of the bacterial populations has a major role on the dissemination of antimicrobial resistance in the environment.     

铋甲西林片的薄层色谱扫描定量分析

建立了铋甲西林片中阿莫西林和甲硝唑的薄层色谱扫描定量分析方法 ,考察了展开剂系统和展开温度对两组分色谱分离的影响情况。采用硅胶 GF2 54 - 0 .50 %羧甲基纤维素钠板 ,以甲醇 -氯仿 -二乙胺 -石油醚 (35∶ 40∶ 1 .0∶ 75)为展开剂 ,两主药斑点经紫外灯定位后 ,不经显色可直接进行双波长薄层色谱扫描测定。以随行外标二点法对样品进行了分析 ,阿莫西林和甲硝唑的回收率分别为 99.82 %和 1 0 0 .9% ,RSD<3.3%。     

New amoxicillin–poly(lactic acid)‐based conjugates: synthesis and in vitro release of amoxicillin

Long‐term antibiotic treatments are required to cure many diseases. Coupling a bioactive compound to a biocompatible polymer offers, in general, many advantages such as better stabilization of drug and controlled release. The work reported deals with the synthesis of new conjugates based on amoxicillin and oligomers of biocompatible and biodegradable poly(lactic acid), as well as release studies of amoxicillin. These new conjugates were obtained via a Curtius rearrangement or acyl chloride activation, leading to substituted urea or amide bonds between amoxicillin and polymer, respectively. Structures of the conjugates were assessed using Fourier transform infrared and ¹H NMR spectroscopy, double‐detection size exclusion chromatography and electrospray ionization mass spectrometry. In vitro release profiles of amoxicillin in phosphate buffered saline were determined using high‐performance liquid chromatography, and the release rates of amoxicillin from the two conjugates were compared. Copyright © 2010 Society of Chemical Industry     

有序介孔碳和活性炭对阿莫西林的吸附研究

阿莫西林是废水中一类典型的药品与个人护理品类新型有机污染物,会对周围环境和人体健康造成潜在威胁。以蔗糖为碳源、以SBA-15为模板制备有序介孔碳（OMC）。采用动态吸附法研究其对阿莫西林的吸附行为,并与常规吸附材料商用活性炭（GAC）作对比。探讨了废水中阿莫西林的初始浓度、温度及流速对动态吸附的影响。结果表明：在同等条件下,OMC的吸附能力远强于GAC,以OMC为吸附剂可有效去除废水中的阿莫西林类新型有机污染物。     

Determination and depletion of amoxicillin residues in eggs

Eggs were used to study the determination and depletion of amoxicillin (AMO) residues after oral dosing hens (25.0 mg kg^–1, 50.0 mg kg^–1 body weight), once daily for five days. A reverse-phase high-performance liquid chromatography with fluorescence detection (RP-HPLC-FLD) method was developed to determine AMO residues in albumen, yolk and whole egg. By using pre-column derivatisation, an improved liquid–liquid extraction procedure was developed for sample preparation. AMO were extracted from eggs with acetonitrile. The extract solution was extracted using saturated methylene chloride. The supernatant was reacted with salicylaldehyde under acidic and heating conditions. Limits of detection (LODs) were 1.2 ng g^–1 and limits of quantification (LOQs) were 3.9 ng g^–1 for AMO. Recoveries of AMO from samples fortified at levels of 5.0–125.0 ng g^–1 ranged from 79.1% to 88.5% in albumen, 78.6–83.6% in yolk and 78.3–85.1% in whole egg, with coefficients of variation of ≤7.3%. The maximum concentrations of AMO in albumen, yolk and whole egg were found to occur at 1.5, 2.5, 1.5 days after withdrawal of medication respectively. AMO was not detectable in albumen at 7.5 days after final administration of AMO, at 10.5–11.5 days in yolk and 10.5 days in whole egg after administration of two oral doses. The method was applied during the residue study of AMO in order to formulate a reasonable withdrawal period to ensure food safety.