Micelle formation

  • 文章类型: Journal Article
    Pemigatinib(PGT)是FDA最近批准的小分子激酶抑制剂,用于治疗成人复发性或难治性髓样/淋巴样肿瘤。这项研究介绍了第一个微孔荧光光谱法(MW-SFM)的开发,用于定量FDA批准的片剂和血浆样品中的PGT。该方法通过阻断光诱导电子转移(PET)和十二烷基硫酸钠(SLS)的胶束化来增强PGT的弱天然荧光。MW-SFM在96微孔板中进行,和使用荧光酶标仪在290nm激发和350nm发射下测量荧光信号。该方法的线性范围为2-250ngmL-1,定量限为6.5ngmL-1。方法的准确度和精密度在96.5%~102.8%范围内,相对标准偏差为1.52%~3.51%。MW-SFM成功分析了Pemazyre®片剂,评估含量均匀性,并分析了掺入PGT的人血浆样品。使用三种不同的度量工具验证了MW-SFM的绿色性。总之,拟议的MW-SFM是支持剂型质量评估的有价值的工具,进行药代动力学研究,并监测治疗结果。
    Pemigatinib (PGT) is a recently FDA-approved small molecule kinase inhibitor used for the treatment of relapsed or refractory myeloid/lymphoid neoplasms in adults. This study introduces the development of a first microwell spectrofluorimetric method (MW-SFM) for quantifying PGT in FDA-approved tablets and plasma samples. The method utilized the enhancement of PGT\'s weak native fluorescence by blocking photoinduced electron transfer (PET) and micellization with sodium lauryl sulfate (SLS). The MW-SFM was performed in 96-microwell plates, and fluorescence signals were measured using a fluorescence microplate reader with excitation at 290 nm and emission at 350 nm. The method exhibited a linear range of 2-250 ng mL-1, and a limit of quantitation was 6.5 ng mL-1. The accuracy and precision of the method were confirmed with recovery rates ranging from 96.5% to 102.8% and relative standard deviations of 1.52% to 3.51%. The MW-SFM successfully analyzed Pemazyre® tablets, assessed content uniformity, and analyzed PGT-spiked human plasma samples. The greenness of the MW-SFM was verified using three different metric tools. In conclusion, the proposed MW-SFM is a valuable tool in supporting quality assessment of dosage forms, conducting pharmacokinetic studies, and monitoring therapeutic outcomes.
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  • 文章类型: Journal Article
    分子相互作用对于稳定无定形固体分散体(ASD)中的无定形药物至关重要。大多数聚合物,然而,与药物形成强分子相互作用的能力有限。为适应要掺入的药物分子的物理化学性质而定制的聚合物,例如,通过允许结合特定的官能团,在这方面将是非常需要的。为此,新型烯丙基封端的聚合物甲氧基(聚乙二醇)-嵌段-聚(茉莉内酯)(mPEG-b-PJL)已被合成并官能化以潜在地增强特定的药物-聚合物相互作用。本研究调查了mPEG-b-PJL在ASD中的使用,使用卡维地洛(CAR),一种弱基础的模型药物。发现揭示了聚合物的酸性官能化形式(mPEG-b-PJL-COOH)与其非官能化对应物mPEG-b-PJL相比确实建立了与CAR的更强的分子相互作用。对形成ASD的聚合物有效性的评估表明,mPEG-b-PJL-COOH在混溶性方面优于其非官能化对应物,载药能力,和稳定性,从降低的分子迁移率推断。然而,溶出测试表明,与单独使用无定形CAR相比,使用mPEG-b-PJL-COOH的ASD并未显着改善溶出行为。尽管通过胶束形成潜在的溶解度增强。总的来说,这项研究证实了官能化聚合物在ASD配方中的潜力,而改善这些ASD的溶解性能的挑战仍然是进一步发展的领域。
    Molecular interactions are crucial to stabilize amorphous drugs in amorphous solid dispersions (ASDs). Most polymers, however, have only a limited ability to form strong molecular interactions with drugs. Polymers tailored to fit the physicochemical properties of the drug molecule to be incorporated, for instance by allowing the incorporation of specific functional groups, would be highly sought-for in this regard. For this purpose, the novel allyl-terminated polymer methoxy(polyethylene glycol)-block-poly(jasmine lactone) (mPEG-b-PJL) has been synthesized and functionalized to potentially enhance specific drug-polymer interactions. This study investigated the use of mPEG-b-PJL in ASDs, using carvedilol (CAR), a weakly basic model drug. The findings revealed that the acidic functionalized form of the polymer (mPEG-b-PJL-COOH) indeed established stronger molecular interactions with CAR compared to its non-functionalized counterpart mPEG-b-PJL. Evaluations on polymer effectiveness in forming ASDs demonstrated that mPEG-b-PJL-COOH outperformed its non-functionalized counterpart in miscibility, drug loading ability, and stability, inferred from reduced molecular mobility. However, dissolution tests indicated that ASDs with mPEG-b-PJL-COOH did not significantly improve the dissolution behaviour compared to amorphous CAR alone, despite potential solubility enhancement through micelle formation. Overall, this study confirms the potential of functionalized polymers in ASD formulations, while the challenge of improving dissolution performance in these ASDs remains an area of further development.
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  • 文章类型: Journal Article
    这项研究的目的是阐明通过在聚(环氧乙烷)(PEO)/聚乙二醇(PEG)基质片剂中利用反聚合物(CP)来延长高水溶性药物的释放机制。卡波默,聚(丙烯酸),被用作CP,与毒品有相反的指控。测试了有或没有CP的PEO/PEG片剂中几种高水溶性药物的体外释放,研究了CP(SRE)的缓释作用与药物理化性质之间的关系。结果表明,CP的利用可以通过有效控制药物在基质中的扩散来延长某些高水溶性药物的释放。另一方面,CP的有效性因所用药物而异.SRE与溶解度等理化性质之间没有统计相关性,分子量,和药物的电荷强度,而药物的胶束形成特性在CP的SRE中起着重要作用。结论是CP,卡波默,具有负电荷可以有效地与稳定药物胶束表面的相反电荷相互作用,这可能导致药物扩散的显着减少,从而导致药物释放延长。人们认为,利用CP的系统是一种有前途的方法,可以实现具有合理片剂大小的高水溶性药物的延长释放。特别是在大量药物负载的情况下。
    The objective of this study is to clarify the mechanism of extending release of highly water-soluble drugs via counter polymer (CP) utilization in poly(ethylene oxide) (PEO)/polyethylene glycol (PEG) matrix tablets. Carbomer, poly(acrylic acid), was used as a CP, which has the opposite charges to the drugs. The in vitro release of several highly water-soluble drugs from PEO/PEG tablet with or without CP were tested, the relationship between the sustained release effect by a CP (SRE) and the physicochemical properties of the drugs was investigated. The results demonstrated that the utilization of CP can extend the release of some highly water-soluble drugs by effectively controlling the drug diffusion through matrices. On the other hand, the effectiveness of CP was different depending on the drugs applied. There were not statistical correlations between SRE and physicochemical properties such as solubility, molecular weight, and charge intensity of the drugs, while a micelle forming property of the drugs played an important role in SRE by CP. It was concluded that CP, Carbomer, having negative charges could effectively interact with opposite charges on the surface of stable drug micelles, which could result in a significant decrease in drug diffusion leading to extended drug release. It is considered that the system utilizing CP is a promising approach to achieve extended release of highly water-soluble drugs with a reasonable tablet size, especially in the case of large drug loading.
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  • 文章类型: Journal Article
    这项研究描述了氯雷他定(LOR)的弱天然荧光的增强通过光诱导电子转移(PET)阻断,然后胶束化为十二烷基硫酸钠胶束的双重策略。增强的荧光被用作开发新的微孔荧光光谱测定法(MW-SFA)的基础,该测定法用于测定其药物剂型和尿液样品中的LOR。该测定在96微孔测定板中进行,通过酶标仪在290和435nm处测量增强的荧光信号,用于激发和发射,分别。建立了测定的最佳条件,生成校准曲线,并计算线性回归方程。在10-2000ngmL-1范围内,荧光信号与LOR浓度呈线性关系,具有良好的测定系数(0.9992)。检测和定量的测定极限分别为4.1和12.5ngmL-1。精度令人满意,相对标准偏差值不超过1.68%,测定的准确度≥99.1%。该建议已成功应用于药物剂型中LOR的分析,具有可接受的准确性和精密度。标签索赔为99.3-100.5%(±0.95-1.59%)。将提出的测定结果与通过报道的预先验证的测定获得的结果进行比较的统计分析显示,在95%置信水平下,两种方法在准确度和精密度方面没有显著差异。该测定法还用于分析含有LOR的尿液样品,准确度≥98.24%。通过三种有效的度量工具证实了所提出的测定的绿色。总的来说,拟议的测定法具有高灵敏度的特点,程序简单,和高吞吐量,能够在短时间内同时分析许多样品。因此,它是在药品质量控制单位和临床实验室中快速常规应用的有价值的工具,用于测定LOR。
    This study describes the enhancement of the weak native fluorescence of loratadine (LOR) by dual strategy via photoinduced electron transfer (PET) blocking followed by micellization into sodium dodecyl sulfate micelles. The enhanced fluorescence was employed as a basis for the development of a novel microwell spectrofluorimetric assay (MW-SFA) for the determination of LOR in its pharmaceutical dosage forms and urine samples. The assay was conducted in 96-microwell assay plates, and the enhanced fluorescence signals were measured by a microplate reader at 290 and 435 nm for excitation and emission, respectively. The optimum conditions of the assay were established, calibration curve was generated, and the linear regression equation was computed. The relation between the fluorescence signals and LOR concentrations was linear with good determination coefficients (0.9992) in the range of 10 - 2000 ng mL-1. The assay limits of detection and quantitation were 4.1 and 12.5 ng mL-1, respectively. The precision was satisfactory, with values of relative standard deviation not exceeding 1.68%, and the assay\'s accuracy was ≥ 99.1%. The proposed was successfully applied to the analysis of LOR in its pharmaceutical dosage forms with acceptable accuracy and precision. The label claims were 99.3 - 100.5% (±0.95 - 1.59%). Statistical analysis comparing the results of the proposed assay with those obtained by a reported pre-validated assay revealed no significant difference between both methods in terms of the accuracy and precision at the 95% confidence level. The assay was also applied to the analysis of urine samples containing LOR with accuracy ≥ 98.24%. The greenness of the proposed assay was confirmed by three efficient metric tools. In overall conclusion, the proposed assay is characterized by high sensitivity, procedure simplicity, and high throughput, enabling the simultaneous analysis of many samples in a short time. Therefore, it is a valuable tool for rapid routine application in pharmaceutical quality control units and clinical laboratories for the determination of LOR.
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  • 文章类型: Journal Article
    由于表面活性剂与金属表面相互作用的强烈倾向,其胶体和腐蚀抑制潜力(CIP)是众所周知的。然而,由于它们的分子尺寸小,而且它们仅在相对较高的浓度下有效,其在水相缓蚀中的应用往往受到限制。高分子表面活性剂,一类独特的缓蚀剂,保持消除与使用表面活性剂抑制腐蚀相关的挑战的潜力。由于它们的大分子聚合结构和大量的极性官能团,它们与金属表面牢固结合,并提供了优越的CIP。与传统的聚合物缓蚀剂相比,极性官能团的加入也有助于它们在大多数流行的基于工业的电解质中的溶解。用于缓蚀的聚合物表面活性剂中存在的一些主要官能团包括O(醚)、缩水甘油(环醚),-CONH2(酰胺),-COOR(酯),-SO3H(磺酸),-COOH(羧基),-NH2(氨基),-+NR3/-+NHR2/-+NH2R/-+NH3(季铵),-OH(羟基),-CH2OH(羟甲基),等。当前的观点提供了有关聚合物表面活性剂作为常规腐蚀抑制剂的新开发理想替代品的最新信息。工业规模扩大,胶体,协调,吸附性能,和聚合物表面活性剂的结构要求也已经基于从文献中获得的知识而建立。最后,挑战,缺点,和使用聚合物表面活性剂的潜在好处也进行了讨论。
    Surfactants are well known for their colloidal and corrosion inhibition potential (CIP) due to their strong propensity to interact with metallic surfaces. However, because of their small molecular size and the fact that they are only effective at relatively high concentrations, their application in aqueous phase corrosion inhibition is often restricted. Polymeric surfactants, a unique class of corrosion inhibitors, hold the potential to eradicate the challenges associated with using surfactants in corrosion inhibition. They strongly bond with the metallic surface and offer superior CIP because of their macromolecular polymeric structure and abundance of polar functional groups. In contrast to conventional polymeric corrosion inhibitors, the inclusion of polar functional groups also aids in their solubilization in the majority of popular industry-based electrolytes. Some of the major functional groups present in polymeric surfactants used in corrosion mitigation include O (ether), glycidyl (cyclic ether), -CONH2 (amide), -COOR (ester), -SO3H (sulfonic acid), -COOH (carboxyl), -NH2 (amino), - + NR3/- + NHR2/- + NH2R/- + NH3 (quaternary ammonium), -OH (hydroxyl), -CH2OH (hydroxymethyl), etc. The current viewpoint offers state-of-the-art information on polymer surfactants as newly developing ideal alternatives for conventional corrosion inhibitors. The industrial scale-up, colloidal, coordination, adsorption properties, and structural requirements of polymer surfactants have also been established based on the knowledge obtained from the literature. Finally, the challenges, drawbacks, and potential benefits of using polymer surfactants have also been discussed.
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  • 文章类型: Journal Article
    α-Gal综合征与针对碳水化合物半乳糖-α-1,3-半乳糖(α-Gal)的IgE的存在有关,其特征是在摄入哺乳动物肉类后2至6小时发生延迟的过敏反应。根据它们的缓慢消化和加工动力学,已经提出携带α-Gal的糖脂作为延迟反应的主要触发因素。
    我们分析并比较了来自天然食物来源的携带α-Gal的糖蛋白和糖脂的体外变应原性。
    从猪肾(PK)中提取蛋白质和脂质,牛肉,和鸡肉。从兔红细胞中纯化糖脂。通过薄层色谱法以及直接和抑制酶联免疫吸附测定评估了α-Gal过敏患者血清(n=39)的α-Gal和IgE结合的存在。通过嗜碱性粒细胞活化试验测定不同肉汁中糖蛋白和糖脂的体外致敏性。通过模拟胃和肠消化测定评价糖蛋白稳定性。
    在PK和牛肉的糖脂上检测到α-Gal。患者IgE抗体识别与糖蛋白和糖脂结合的α-Gal,尽管与糖蛋白的结合更有效。兔糖脂能够强烈激活患者嗜碱性粒细胞,而来自PK和牛肉的脂质提取物也被发现触发嗜碱性粒细胞活化,但与各自的蛋白质提取物相比,容量较低。PK的模拟胃消化试验表明,PK中携带α-Gal的蛋白质具有很高的稳定性。
    携带α-Gal的糖蛋白和糖脂都能够强烈激活患者嗜碱性粒细胞。在PK和牛肉中,α-Gal表位在糖脂上似乎不如在糖蛋白上丰富,提示糖蛋白在食用这些食物来源后的延迟过敏反应中的主要作用。
    The α-Gal syndrome is associated with the presence of IgE directed to the carbohydrate galactose-α-1,3-galactose (α-Gal) and is characterized by a delayed allergic reaction occurring 2 to 6 hours after ingestion of mammalian meat. On the basis of their slow digestion and processing kinetics, α-Gal-carrying glycolipids have been proposed as the main trigger of the delayed reaction.
    We analyzed and compared the in vitro allergenicity of α-Gal-carrying glycoproteins and glycolipids from natural food sources.
    Proteins and lipids were extracted from pork kidney (PK), beef, and chicken. Glycolipids were purified from rabbit erythrocytes. The presence of α-Gal and IgE binding of α-Gal-allergic patient sera (n = 39) was assessed by thin-layer chromatography as well as by direct and inhibition enzyme-linked immunosorbent assay. The in vitro allergenicity of glycoproteins and glycolipids from different meat extracts was determined by basophil activation test. Glycoprotein stability was evaluated by simulated gastric and intestinal digestion assays.
    α-Gal was detected on glycolipids of PK and beef. Patient IgE antibodies recognized α-Gal bound to glycoproteins and glycolipids, although binding to glycoproteins was more potent. Rabbit glycolipids were able to strongly activate patient basophils, whereas lipid extracts from PK and beef were also found to trigger basophil activation, but at a lower capacity compared to the respective protein extracts. Simulated gastric digestion assays of PK showed a high stability of α-Gal-carrying proteins in PK.
    Both α-Gal-carrying glycoproteins and glycolipids are able to strongly activate patient basophils. In PK and beef, α-Gal epitopes seem to be less abundant on glycolipids than on glycoproteins, suggesting a major role of glycoproteins in delayed anaphylaxis upon consumption of these food sources.
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  • 文章类型: Journal Article
    严格分析了表面活性剂混合物的表面活性。Cat-阴离子系统,其中两种离子以非化学计量比混合,被考虑。关于解决方案行为,与纯组分相比,cmc大幅下降,对表面张力的适度影响,γ,发生。与纯物种相比,这种混合物的表面张力降低并不显著,并且不满足对阴离子/阳离子摩尔分数的明显依赖性。表面张力在整个浓度范围内大致恒定。相反,曲面的交互参数,βsurf(由正则解理论计算),比胶束形成更负面,βmic。这一事实表明,两种物种的极头在界面处的去溶剂化有很大不同。很可能,根本原因在于两个极头基团的大小和溶剂化。
    The surface activity of surfactant mixtures is critically analyzed. Cat-anionic systems, in which two ionic species are mixed in non-stoichiometric ratios, are considered. With respect to the solution behavior, where a substantial decrease of cmc is met compared to the pure components, a moderate effect on surface tension, γ, occurs. Compared to the pure species, the decrease of surface tension for such mixtures is not significant, and no clear dependence on the mole fraction anionic/cationic is met. The surface tension is grossly constant in the whole concentration range. Conversely, the interaction parameter for surfaces, β surf (calculated by the regular solution theory), is more negative than that for micelle formation, β mic . This fact suggests that the desolvation of polar heads of the two species at interfaces is largely different. Very presumably, the underlying rationale finds origin in the sizes and solvation of both polar head groups.
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  • 文章类型: Journal Article
    Polysorbates (PSs, Tweens) are widely used surfactant products consisting of a sorbitan ring connecting up to four ethylene oxide (EO) chains of variable lengths, one or more of which are esterified with fatty acids of variable lengths and saturation degrees. Pharmaceutical applications include the stabilization of biologicals in solutions and the solubilization of poorly water soluble, active ingredients. This study characterizes the complex association behavior of compendial PSs PS20 and PS80, which is fundamentally different from that of single-component surfactants. To this end, a series of demicellization experiments of isothermal titration calorimetry with different PS concentrations are evaluated. Their experiment-dependent heats of titration are converted into a common function of the state of a sample, the micellar enthalpy Qm(c). These functions demonstrate that initial micelles are already present at the lowest concentrations investigated, 2 μM for PS20 and 10 μM for PS80. Initial micelles consist primarily of the surfactant species with the lowest individual critical micelle concentration (cmc). With increasing concentration, the other PS species gradually enter these micelles in the sequence of increasing individual cmc\'s and hydrophilic-lipophilic balance. Concentration ranges with pronounced slopes of Qm(c) can be tentatively assigned to the uptake of the major components of the PS products. Micellization and the variation of the micelle properties progress up to at least 10 mM PS. That means the published cmc values or ranges of PS20 and PS80 may be related to certain, major components being incorporated into and forming specific micelles but must not be interpreted in terms of an absence of micelles below and constant properties, e.g., the surface activity, of the micelles above these ranges. The micellization enthalpy curves differ quite substantially between PS20 and PS80 and, in a subtler fashion, between individual quality grades such as high purity, pure lauric acid/pure oleic acid, super-refined, and China grade.
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  • 文章类型: Journal Article
    Isothermal titration calorimetry is frequently employed to determine the critical micelle concentration and the micellization enthalpy of surfactants in terms of geometrical characteristics of the titration curves. Previously we have shown theoretically that even for an infinitesimal injection, the heat per titrant mol depends on the stock solution concentration. In this work, we explore experimentally the influence of the stock solution concentration on the geometrical characteristics of the titration curve and its effect in determining the critical micelle concentration and the micellization enthalpy of surfactants. The systematic study of this phenomenology involves a great number of measurements at different temperatures with several repetitions carried out using a robotic calorimeter. As surfactant hexadecyltrimethylamonium bromide was used. The magnitude and shape of the heat titration depend on the stock solution concentration. As a consequence, the inflexion-point, break-point, and step-height decrease until a limiting value. A qualitative analysis suggests that the limiting value depends only on substance. This work shows that graphical methods could not be suitable for the calculation of the critical micelle concentration and micellization enthalpy because the magnitude and shape of the titration curve depend on the stock solution concentration. Micellar properties should be calculated by the application of theoretical models as in the ligand-binding studies.
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  • 文章类型: Journal Article
    Anionic surfactants denature proteins at low millimolar concentrations, yet little is known about the underlying molecular mechanisms. Here, we undertake 1-μs-long atomistic molecular dynamics simulations of the denaturation of acyl coenzyme A binding protein (ACBP) and compare our results with previously published and new experimental data. Since increasing surfactant chain length is known to lead to more rapid denaturation, we studied denaturation using both the medium-length alkyl chain surfactant sodium dodecyl sulfate (SDS) and the long alkyl chain surfactant sodium hexadecyl sulfate (SHS). In silico denaturation on the microsecond timescale was not achieved using preformed surfactant micelles but required ACBP to be exposed to monomeric surfactant molecules. Micellar self-assembly occurred together with protein denaturation. To validate our analyses, we calculated small-angle X-ray scattering spectra of snapshots from the simulations. These agreed well with experimental equilibrium spectra recorded on ACBP-SDS mixtures with similar compositions. Protein denaturation occurs through the binding of partial micelles to multiple preferred binding sites followed by the accretion of surfactant monomers until these partial micelles merge to form a mature micelle and the protein chain is left disordered on the surface of the micelle. While the two surfactants attack in a similar fashion, SHS\'s longer alkyl chain leads to a more efficient denaturation through the formation of larger clusters that attack ACBP, a more rapid drop in native contacts, a greater expansion in size, as well as a more thorough rearrangement of hydrogen bonds and disruption of helices.
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