Physicochemical properties

物理化学性质
  • 文章类型: Journal Article
    共晶工程,这涉及通过非共价相互作用将两种或多种组分自组装成固态超分子结构,已成为定制活性药物成分(API)的物理化学性质的有希望的方法。共晶的有效共形成物筛选仍然是一个挑战。在这里,采用基于机器学习算法的预测策略来预测共晶形成,并成功构建了7个精度超过0.890的可靠模型。选择伊马替尼作为模型药物,并将建立的模型用于筛选31种潜在的共形成剂。实验验证结果表明,RF-8是7个模型中的最优模型,精度为0.839。当这七个模型被组合用于IM的共形成物筛选时,组合模型的精度达到0.903,并观察和表征了八个新的固体形式。受益于分子间相互作用,获得的多组分晶体显示出增强的物理化学性质。溶出度和溶解度实验表明,所制备的多组分晶体具有较高的累积溶出度,显著提高了伊马替尼的溶解度,和IM-MC表现出与IM甲磺酸酯α形式相当的溶解度。稳定性测试和细胞毒性结果表明,多组分晶体表现出优异的稳定性,药物-药物共晶体IM-5F表现出比纯API更高的细胞毒性。
    Cocrystal engineering, which involves the self-assembly of two or more components into a solid-state supramolecular structure through non-covalent interactions, has emerged as a promising approach to tailor the physicochemical properties of active pharmaceutical ingredient (API). Efficient coformer screening for cocrystal remains a challenge. Herein, a prediction strategy based on machine learning algorithms was employed to predict cocrystal formation and seven reliable models with accuracy over 0.890 were successfully constructed. Imatinib was selected as the model drug and the models established were applied to screen 31 potential coformers. Experimental verification results indicated RF-8 is the optimal model among seven models with an accuracy of 0.839. When the seven models were combined for coformer screening of Imatinib, the combinational model achieved an accuracy of 0.903, and eight new solid forms were observed and characterized. Benefiting from intermolecular interactions, the obtained multicomponent crystals displayed enhanced physicochemical properties. Dissolution and solubility experiments showed the prepared multicomponent crystals had higher cumulative dissolution rate and remarkably improved the solubility of imatinib, and IM-MC exhibited comparable solubility to Imatinib mesylate α form. Stability test and cytotoxicity results showed that multicomponent crystals exhibited excellent stability and the drug-drug cocrystal IM-5F exhibited higher cytotoxicity than pure API.
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  • 文章类型: Journal Article
    开发前药是克服候选药物的一些缺点的有用策略。最近,我们建立了选择适当前药的系统方法,并使用奥司他韦类似物验证了该方法的实用性。在这项研究中,使用坎地沙坦西酯及其20种具有各种类型侧链的类似物作为模型化合物,进一步检验了该方法的实用性。类似物的LogD值(2.5至4.7)高于坎地沙坦(1.0),它们的活性代谢物,结果对于改善坎地沙坦的渗透性是合理的。类似物倾向于在人工肠液中比在人工胃液中更易溶,由于它们的酸性物理化学特征。它们的膜渗透率与logD值无关,这可以归因于该系统中使用的Caco-2细胞中的代谢。在人类肝细胞和肠细胞中,20种类似物中的11种立即水解成坎地沙坦,并观察到水解效率的物种差异。这项研究证实了选择合适的前药的系统方法的实用性,可以进行体内药代动力学研究,选择合适的实验动物。
    Development of prodrugs is a useful strategy to overcome some disadvantages of candidate drugs. Recently, we established a systematic approach to selecting appropriate prodrugs, and validated the utility of this approach using oseltamivir analogues. In this study, the utility of the approach was further examined using candesartan cilexetil and 20 kinds of its analogues having various types of side chain as model compounds. Log D values of analogues (2.5 to 4.7) were higher than that of candesartan (1.0), their active metabolite, and the results were reasonable for the purpose of improving permeability of candesartan. The analogues tended to be more soluble in artificial intestinal fluids than in artificial gastric fluid, owing to their acidic physicochemical characteristics. Their membrane permeabilities were not correlated with log D values, which can be attributed to the metabolism in Caco-2 cells used in this system. In human hepatocytes and enterocytes, 11 out of the 20 analogues were immediately hydrolyzed to candesartan, and species differences were observed in the hydrolysis efficiency. This study confirmed the utility of the systematic approach for selection of appropriate prodrugs that could be proceeded to in vivo pharmacokinetics study, with selection of suitable experimental animals.
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  • 文章类型: Journal Article
    乌干达的木薯育种计划目前没有根据制粉质量选择材料,部分解释了许多发布品种的采用率低。在这项研究中,我们描述最终用户特征偏好,木薯粉的加工品质和理化性质。我们发现,在这项研究中评估的木薯面粉质量的大多数属性中,女性的比例高于男性。男女对颜色的偏好分别为66%和52%,分别,而Kwon的粘性为26%(女性)和15%(男性)。Kwon的易剥性和粘性是关键加工性状。堆发酵面粉的糊化温度较高,但粘度比晒干的面粉低,与新鲜根淀粉相比,直链淀粉含量较低。结果表明,对育种材料进行性别敏感的参与性评估的重要性,在选择最佳候选育种品系期间与物理化学评估相结合。
    Cassava breeding programmes in Uganda do not currently select materials based on flour making quality, explaining in part the low adoption rates of many released varieties. In this study, we describe end user trait preferences, processing qualities and physicochemical properties of cassava flour. We found that higher proportion of women than men showed preference for most attributes of cassava flour quality evaluated in this study. Preference for colour was 66% and 52% among women and men, respectively, while that for stickiness of Kwon was 26% (women) and 15% (men). Ease of peeling and stickiness of Kwon were key processing traits. Heap fermented flour had higher pasting temperatures, but lower viscosities than sun-dried flour, and had lower amylose content compared to fresh root starch. The results demonstrate the importance of gender sensitive participatory evaluation of breeding materials, in tandem with physicochemical evaluation during selection of best possible candidate breeding lines.
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  • 文章类型: Journal Article
    Various screening approaches are used by industry to evaluate development risks associated with discovery candidates. This process has become more complicated with biological therapeutics, a class dominated by monoclonal antibodies (mAb), and, increasingly, their derivative constructs. Effective early assessment for drug-like properties (DLP) can save time and costs by allowing a more complete consideration of issues that could impact the desired end result of a stable drug product. Here we report a case study of four IgG1 mAbs, with sequence variations in the variable domain region, screened as a set of possible drug candidates. Our comprehensive, tiered approach used a battery of analytical tools to assess molecular characteristics, conformational stability, colloidal stability, and short-term storage stability. While most DLP for the four candidates were developmentally acceptable and comparable, mAb-2 was associated with adverse colloidal properties. Further investigation of mAb-2 in an expanded pH range revealed a propensity for phase separation, indicating a need for the additional product development effort. Our results support that comprehensive DLP assessments in an expanded pH range are beneficial in identifying development options for promising molecules that show challenging stability trends. This adaptable approach may be especially useful in the development of increasingly complex antibody constructs.
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  • 文章类型: Journal Article
    Identification of the biopharmaceutical risks of excipients and excipient variability on oral drug performance can be beneficial for the development of robust oral drug formulations. The current study investigated the impact of Hypromellose (HPMC) presence and varying viscosity type, when used as a binder in immediate release formulations, on the apparent solubility of drugs with wide range of physicochemical properties (drug ionization, drug lipophilicity, drug aqueous solubility). The role of physiological conditions on the impact of excipients on drug apparent solubility was assessed with the use of pharmacopoeia (compendial) and biorelevant media. Presence of HPMC affected drug solubility according to the physicochemical properties of studied compounds. The possible combined effects of polymer adsorption (drug shielding effect) or the formation of a polymeric viscous layer around drug particles may have retarded drug dissolution leading to reduced apparent solubility of highly soluble and/or highly ionized compounds and were pronounced mainly at early time points. Increase in the apparent solubility of poorly soluble low ionized drugs containing a neutral amine group was observed which may relate to enhanced drug solubilization or reduced drug precipitation. The use of multivariate data analysis confirmed the importance of drug physicochemical properties on the impact of excipients on drug apparent solubility and revealed that changes in HPMC material properties or amount may not be critical for oral drug performance when HPMC is used as a binder. The construction of a roadmap combining drug, excipient, and medium characteristics allowed the identification of the cases where HPMC presence may present risks in oral drug performance and bioavailability.
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  • 文章类型: Comparative Study
    Renaissance of cocrystals as alternative solid forms for fine-tuning physicochemical properties of active pharmaceutical ingredients (APIs) has paved way for development of marketable cocrystals. The current literature reveals established strategies for the design, synthesis and characterization of cocrystals. However, barring a few isolated case studies, strategies for development of cocrystal formulations have been underdeveloped. Herein we report topical formulations of an antioxidant, ferulic acid (FA), which contain the active in its cocrystal form. Cocrystals of FA with the coformers relevant to skin care such as urea, nicotinamide (NA) and isonicotinamide (INA) have been prepared and oleogel formulations of these have been developed. The cocrystal with urea and an anhydrous cocrystal with INA have been identified for the first time in this study. The novel cocrystals were structurally characterized by single crystal X-ray diffraction. Solubility and stability studies have revealed higher solubility of the cocrystals with NA and INA than the parent active and greater stability of FA in formulations that contained the cocrystals with INA and urea than the corresponding formulations containing physical mixtures or parent active. In vitro membrane permeation tests have ascertained sustained release profile of active from the formulation that contained the FA•INA cocrystal. The higher solubility, greater stability and sustained active release profile of the FA•INA cocrystal formulation make it a promising topical formulation of FA.
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  • 文章类型: Journal Article
    这项工作的重点是评估将使用过的食用油(UCO)用作城市生物精炼厂的油脂化学原料的潜力。该研究案例是为波哥大市开发的,哥伦比亚。最初,根据主要油脂分销商的数据,市场信息,和公共数据库,据估计,哥伦比亚每年的UCOs总发电量约为22.5万吨,人均为ca。5kg/人/年。相应地,波哥大的UCO产量估计至少为45,000吨/年。,主要一代人发生在家庭和霍雷卡(酒店,餐厅和餐饮)细分市场。特别是在霍雷卡,快餐店(尤其是汉堡包和鸡肉)被确定为主要的UCO发电机,为工业开发提供了合适的供应。然后,来自这部分餐馆的UCOs样品通过密度测定进行物理化学表征,挥发物含量,酸值,颜色,过氧化值,皂化值,碘值,和总极性化合物的含量。与油的降解程度相关的性质表现出很大的变化,即使是来自同一来源的样本。这种异质性表明在重复使用之前需要预处理过程。尽管样本的异质性,密度,碘值,不同餐厅的皂化值略有变化,很大程度上取决于加工食用油的性质,而不是烹饪条件。收集的UCOs显示碘值和皂化指数在80至119gI2/100g之间,和178-201毫克KOH/克,分别。这表明在适当的纯化后,UCO可以用作各种高价值油脂化学品的原料。最后,根据市场数据,并促进进一步的研究,确定了一些期许增值衍生品。
    This work is focused on assessing the potential for the exploitation of used cooking oils (UCOs) as oleochemical feedstock for urban biorefineries. The study case was developed for the city of Bogotá, Colombia. Initially, and according to data from major fats and oils distributors, market information, and public databases, it was estimated that total annual generation of UCOs in Colombia is about 225,000 t, with a per capita of ca. 5 kg/person/yr. Correspondingly, UCOs generation in Bogotá was estimated in at least 45,000 t/yr., with a major generation occurring at Household and HORECA (Hotels, Restaurants and Catering) segments. Specifically in HORECA, fast food restaurants (in particular those of hamburger and chicken) were identified as the main UCOs generators with a suitable supply for industrial exploitation. Then, UCOs samples from this segment of restaurants were subjected to physicochemical characterization by determination of density, volatile matter content, acid value, color, peroxide value, saponification value, iodine value, and content of total polar compounds. The properties associated with the degree of degradation of the oil showed a large variation, even among samples from the same origin. This heterogeneity indicates the need for a pre-treatment process before its reuse. Despite the heterogeneity of the samples, density, iodine value, and saponification value showed slight changes among the different restaurants, largely depending on the nature of the processed cooking oil rather than on the cooking conditions. The collected UCOs showed iodine values and saponification indexes ranging between 80 and 119 g I2/100 g, and 178-201 mg KOH/g, respectively. This indicates that after a suitable purification, UCOs could be used as raw material for a variety of high value oleochemicals. Finally, based upon market data, and to boost further studies, some promissory value-added derivatives are identified.
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  • 文章类型: Journal Article
    在离子液体(ILs)领域,理论驱动的建模方法旨在通过使用独特的,通常是非线性的,定量结构-性质关系(QSPR)模型已被广泛采用。在这种情况下,我们提出了化学信息学和化学计量学数据驱动的程序,这些程序导致具有局部有效性的QSPR软模型,能够预测IL的相关物理化学性质,如粘度,密度,分解温度,和导电性。这些模型,它使用随时可用且易于解释的VolSurf描述符,为实验人员在工业研发设计中建模和预测IL的物理化学性质提供了未利用的机会。
    In the field of ionic liquids (ILs), theory-driven modeling approaches aimed at the best fit for all available data by using a unique, and often nonlinear, model have been widely adopted to develop quantitative structure-property relationship (QSPR) models. In this context, we propose chemoinformatic and chemometric data-driven procedures that lead to QSPR soft models with local validity that are able to predict relevant physicochemical properties of ILs, such as viscosity, density, decomposition temperature, and conductivity. These models, which use readily available and easily interpretable VolSurf+ descriptors, represent an unexploited opportunity for experimentalists to model and predict the physicochemical properties of ILs in industrial R&D design.
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  • 文章类型: Journal Article
    日本的一些农场,即未施肥的农场(UF),在不施用化肥或堆肥的情况下,能够保持高生产率超过40年。这项研究旨在表征物理化学,与Eniwa和Nariita的对照农场相比,UF中土壤的生物学和微形态特性,并确定与作物生产力相关的特征。在UF中,没有观察到犁盘。UFs的有效土壤深度(ESD)的厚度大于CFs的厚度。土壤有机碳的浓度,UFsESD中的总氮和硝酸盐氮高于CFsESD中的总氮和硝酸盐氮。土壤微观结构的观察表明,颗粒状微观结构的强烈发展,在UF的地表和地下地层中都具有大量的空隙空间和较高的分形维数。干产率与ESD厚度和空隙的分形维数有很强的相关性。因此,未施肥栽培的管理促进了A层和B层土壤聚集的发展。ESD的增加,随着底土结构的发展,土壤孔隙空间和复杂性提高了未施肥栽培的生产力。
    Certain farms in Japan, namely unfertilised farms (UFs), have been able to maintain high productivity for over 40 years without applying fertilisers or composts. This study aimed to characterise the physicochemical, biological and micromorphological properties of soil in UFs compared with control farms in Eniwa and Nariita and to identify characteristics that are associated with crop productivity. In UFs, no plough pan was observed. The thickness of the effective soil depth (ESD) of UFs was greater than that of CFs. The concentrations of soil organic carbon, total nitrogen and nitrate-nitrogen in ESD of UFs were higher than those in ESD of CFs. Soil microstructure observations indicated the strong development of a granular microstructure with large amounts of void space and a high fractal dimension in both surface and subsoil horizons of UFs. Dry yield had a strong correlation with ESD thickness and fractal dimension of voids. Thus, the management of unfertilised cultivation promoted the development of soil aggregation in both A and B horizons. The increase in ESD, soil pore spaces and complexity with the development of subsoil structure improved the productivity of unfertilised cultivation.
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