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1.
Antimicrobial polyamide (PA) received much attention for the demand of packaging and biomedical fields. In this paper, an antimicrobial PA6 membrane was prepared via a surface chemical reaction. A highly effective antibacterial component (PHMG‐E) with terminal epoxy group was firstly synthesized via a reaction between polyhexamethylene guanidine hydrochloride (PHMG) and ethylene glycol diglycidyl ether (EGDE). Then, PHMG‐E was bonded on the surface of PA6 membrane with secondary amine reduced by borane‐tetrahydrofuran (BH3‐THF). The antimicrobial rates of surface‐modified PA6 membrane (PA6‐PHMG) against Escherichia coli and Staphylococcus aureus were both higher than 99.99%, and the PHMG was non‐leaching due to the chemical bonding. The hydrophilicity of antibacterial PA6 membrane was also significantly improved and the mechanical performance became better. 相似文献
2.
Luis Eduardo Serrano-Mora María L. Zambrano-Zaragoza Nstor Mendoza-Muoz Gerardo Leyva-Gmez Zaida Urbn-Morln David Quintanar-Guerrero 《Molecules (Basel, Switzerland)》2021,26(7)
The purpose of the study was to develop a novel, directly compressible, co-processed excipient capable of providing a controlled-release drug system for the pharmaceutical industry. A co-processed powder was formed by adsorption of solid lipid nanoparticles (SLN) as a controlled-release film onto a functional excipient, in this case, dicalcium phosphate dihydrate (DPD), for direct compression (Di-Tab®). The co-processed excipient has advantages: easy to implement; solvent-free; industrial scaling-up; good rheological and compressibility properties; and the capability to form an inert platform. Six different batches of Di-Tab®:SLN weight ratios were prepared (4:0.6, 3:0.6, 2:0.6, 1:0.6, 0.5:0.6, and 0.25:0.6). BCS class III ranitidine hydrochloride was selected as a drug model to evaluate the mixture’s controlled-release capabilities. The co-processed excipients were characterized in terms of powder rheology and dissolution rate. The best Di-Tab®:SLN ratio proved to be 2:0.6, as it showed high functionality with good flow and compressibility properties (Carr Index = 16 ± 1, Hausner Index = 1.19 ± 0.04). This ratio could control release for up to 8 h, so it fits the ideal profile calculated based on biopharmaceutical data. The compressed systems obtained using this powder mixture behave as a matrix platform in which Fickian diffusion governs the release. The Higuchi model can explain their behavior. 相似文献
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液相色谱-串联质谱同时测定禽肉组织中盐酸金刚烷胺、盐酸金刚乙胺、地塞米松、替米考星及喹乙醇代谢物的残留量 总被引:3,自引:0,他引:3
建立了同时测定禽肉组织中盐酸金刚烷胺、盐酸金刚乙胺、地塞米松、替米考星及喹乙醇代谢物残留量的液相色谱-串联质谱分析方法。样品用2 mol/L氢氧化钠溶液水解,盐酸调节p H值后,以乙腈作为提取溶剂,经C18固相萃取柱净化。各待测物分别经0.1%甲酸甲醇溶液和氨化甲醇(0.1%氨水)洗脱,Phenomenex Kinetex C18(100 mm×4.6 mm,2.6μm)色谱柱进行分离,采用0.1%甲酸(含5 mmol/L乙酸铵)-甲醇作流动相,梯度洗脱,串联质谱法对5种药物含量进行测定。结果表明,5种药物在2~100μg/L范围内线性关系良好,相关系数为0.996 2~0.999 8。在加标浓度为5~50μg/kg的禽肉组织中,这5种药物的加标回收率为73.7%~92.3%,相对标准偏差(n=5)为3.9%~16.6%,检出限为0.2~3.0μg/kg,定量下限为0.7~10μg/kg。方法快速、简便、经济实用,符合法规要求,可满足日常检测的需要。 相似文献
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在碱性介质中,盐酸异丙嗪对luminol-KMnO4发光体系有显著的增强作用.基于此增强作用,建立了一种FI-CL检测盐酸异丙嗪的新方法.在最优化的实验条件下,盐酸异丙嗪的ΔICL强度与其浓度在7.0×10-9~9.0×10-7 mol/L浓度范围内有较好的线性关系.线性方程为ΔICL=35.19+1.19×10-10 c,相关系数r=0.998 4,检出限为4.9×10-9 mol/L.对7.0×10-9 mol/L的盐酸氯丙嗪标准溶液进行11次平行测定,其RSD为2.4%.盐酸异丙嗪加标回收率在89.1%~96.1%之间. 相似文献
6.
The present study is aimed to investigate the degree of crystallinity of poly(3-hydroxybutyrate) P(3HB) grafted with poly(2-aminoethyl methacrylate hydrochloride) (PAEMA) chains using WAXS, micro Raman, and FTIR spectroscopy. The samples were obtained by radiation induced graft polymerization of the monomer in the substrate using different solvents for comparison. The results of crystallinity are consistent with those obtained of lower crystallinity in grafting copolymer relative to the substrate P(3HB). The low crystallinity is directly related to the increase of the degree of grafting, meaning that although the P(3HB) amorphous region is grafted, the crystalline zone is also affected in some extent by the grafting process and the environment of the new molecule. Three different methods were surveyed to determine the variation of crystallinity degree with the grafting degree. It is shown that all methods provide linear relationships between these variables, but WAXS method was found more acceptable than the others (FTIR and Raman). A detailed characterization of the vibrational bands characteristic of amorphous and helical crystalline structure of the grafting copolymers are also highlighted. 相似文献
7.
A novel method is developed for the direct determination of naphazoline hydrochloride(NAP) and pyridoxine hydrochloride(VB6) in commercial eye drops. By using excitation–emission matrix(EEM)fluorescence coupled with second-order calibration method based on the alternating trilinear decomposition(ATLD) algorithm, the proposed approach can achieve quantitative analysis successfully even in the presence of unknown and uncalibrated interferences. The method shows good linearity for NAP and VB6 with correlation coefficients greater than 0.99. The results were in good agreement with the labeled contents. To further confirm the feasibility and reliability of the proposed method, the same batch samples were analyzed by multiple reaction monitoring(MRM) based on LC–MS/MS method.T-test demonstrated that there are no significant differences between the prediction results of the two methods. The satisfactory results obtained in this work indicate that the use of the second-order calibration method coupled with the EEM is a promising tool for industrial quality control and pharmaceutical analysis due to its advantages of high sensitivity, low-cost and simple implementation. 相似文献
8.
合成了新型的具有长链的二茂铁衍生物(P-Fc),并将其包络在2-羟丙基-β-环糊精(HP-β-CD)的空腔中,自组装形成超分子囊泡,并通过FTIR、1 HNMR、SEM和CV曲线对其进行结构形貌表征;分别以罗丹明6G(R6G)、盐酸阿霉素(DOX)作为药物,实现了R6G、DOX在囊泡中的成功装载。并通过加入氧化剂,将二茂铁氧化成二茂铁盐,将囊泡破坏,实现了 R6G 和 DOX 的快速定向释放,其药物装载量分别为6.89和39.06μg/mg,最大释放率分别为73.7%和88.2%。 相似文献
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