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排序方式: 共有448条查询结果,搜索用时 15 毫秒
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目的:研究虫草素提取液的稳定性及酸碱溶解度,为虫草素的进一步开发利用奠定基础。方法利用75%乙醇、45℃超声波浸提虫草素的提取液对虫草素的稳定性、在酸碱溶液中的溶解度等进行了研究。结果虫草素对光的稳定性较差,光照可导致其分解;对温度的稳定性不高;维生素中,VA 不利于虫草素的保存,VB、VC、VE均有利于虫草素的保存;随着溶液碱性的增强虫草素的溶解度略微降低,溶液酸性越强虫草素越不易溶解。结论通过对虫草素提取液稳定性的初步研究,以期为虫草素的进一步开发利用奠定基础。 相似文献
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《Saudi Pharmaceutical Journal》2019,27(4):491-501
Baricitinib is a recently approved anti-rheumatic drug having very poor aqueous solubility and hence its performance suffers from low or inconsistent oral bioavailability. The purpose of the study was to develop and evaluate poly lactic-co-glycolic acid (PLGA) nanoparticles of baricitinib in order to enhance in vitro dissolution and performance. Nano-suspension of baricitinib with or without PLGA, a biodegradable, FDA approved semi-synthetic polymer, was developed by nanoprecipitation method. Research methodology employed a quantitative research utilizing experimental design wherein effect of independent variables such as amount of polymer, drug: polymer ratio, types of solvent, and solvent: anti-solvent ratio were evaluated over the size and size distribution of nanoparticles along with entrapment efficiencies. Among the several organic phases evaluated, acetone was found to be suitable solvent for drug and polymer. The aqueous phase (anti-solvent) was deionized water containing 1% w/v pluronic 127 as the stabilizer of nanoparticle suspension. The optimized nanoparticles had particle size less than 100 nm (91 nm ± 6.23) with a very narrow size distribution (0.169 ± 0.003), high zeta potential (−12.5 mV ± 5.46) and entrapment efficiency (88.0%). The optimized nanoparticles were characterized by scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, infrared spectroscopy and in vitro dissolution studies. In-vitro dissolution study of PLGA nanoparticles exhibited sustained release with approximately 93% release of baricitinib during 24-h period. 相似文献
4.
《Saudi Pharmaceutical Journal》2020,28(1):15-24
Albendazole (ABZ, anti-parasitic active pharmaceutical ingredient) is a crystalline low water-soluble drug, thus the dissolution rate in gastrointestinal fluids is limited. Consequently, the improvement of the water solubility and dissolution rate of ABZ implies a great challenge for a more efficient treatment of hydatidosis. In this context, SBA-15 and SBA-16 ordered mesoporous silica materials were synthetized and loaded with ABZ. X-ray diffraction, FT-IR spectroscopy, nitrogen physisorption manometry, particle size distribution and scanning electronic microscopy were used to characterize unloaded and loaded materials (ABZ/SBA-15 and ABZ/SBA-16). The loaded ABZ amount in the carriers was estimated by elemental analysis. For the loaded materials, the drug solubility and release profile were evaluated. In addition, mathematical models were compared to explain the dissolution kinetics of ABZ from mesoporous solids. ABZ was successfully loaded into the mesopores. The amorphous state of the adsorbed ABZ was confirmed by differential scanning calorimetry that resulted in a notable increment in the dissolution rate compared to crystalline ABZ. Drug release behaviors were well simulated by the Weibull model for ABZ/SBA-15 and by the Gompertz function for pure ABZ and ABZ/SBA-16. The SBA-15 carrier exhibited the highest drug loading and dissolution rate becoming a promising material to improve ABZ bioavailability. 相似文献
5.
《Burns : journal of the International Society for Burn Injuries》2022,48(4):860-871
Topical drug therapy is one of the most effective approaches in third-degree burn wound treatments. To optimize and enhance drug permeation through burn eschar, we need to characterize this barrier, most importantly, its affinity to drugs; the subject of this investigation.Hansen Solubility Parameters (HSP), as polarity and affinity scale, were measured here for human third-degree burn eschar through uptake studies using 19 solvents at 25 °C and 32 °C and two hydration levels by gravimetric method combined with thermal analysis and Karl Fischer titration. HSP parameters of dispersion (δD), bipolar (δP), and hydrogen bonding (δH) were calculated by HSPiP software.Results showed δD, δP, and δH of 17.0, 12.5, 14.6 and 16.8, 12.4, 14.4 at 25 and 32 °C respectively for normally-hydrated samples. Full hydration increased HSP values to 17.2, 12.9, 15.3 (25 °C) and 17.1, 12.8, 15.1 (32 °C). Good correlations between solvents uptakes and HSP values were observed for all parameters; higher for δP. Increased temperature decreased them with more changes in δH. Relative Energy Differences (RED) were calculated and shown to be a good parameter for predicting drug-eschar affinity.The obtained information is useful for drug selection and carrier design in drug delivery through burn eschar. 相似文献
6.
《药学学报(英文版)》2020,10(2):327-343
Our recent studies demonstrated that the natural product nobiletin (NOB) served as a promising multidrug resistance (MDR) reversal agent and improved the effectiveness of cancer chemotherapy in vitro. However, low aqueous solubility and difficulty in total synthesis limited its application as a therapeutic agent. To tackle these challenges, NOB was synthesized in a high yield by a concise route of six steps and fourteen derivatives were synthesized with remarkable solubility and efficacy. All the compounds showed improved sensitivity to paclitaxel (PTX) in P-glycoprotein (P-gp) overexpressing MDR cancer cells. Among them, compound 29d exhibited water solubility 280-fold higher than NOB. A drug-resistance A549/T xenograft model showed that 29d, at a dose of 50 mg/kg co-administered with PTX (15 mg/kg), inhibited tumor growth more effective than NOB and remarkably increased PTX concentration in the tumors via P-gp inhibition. Moreover, Western blot experiments revealed that 29d inhibited expression of NRF2, phosphorylated ERK and AKT in MDR cancer cells, thus implying 29d of multiple mechanisms to reverse MDR in lung cancer. 相似文献
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In chemical industry, usual solvents are being replaced by supercritical fluids. Last few years, extraction by these environmentally benign solvents has had much attention and now is considered as the newest separation technology. However, developing new applications and improving existing ones is based on a set of thermodynamic and physical properties of pure solutes related to phase equilibrium for which experimental values cannot be found and consequently, there is an increase need for accurate estimates of these properties. This paper is interested firstly to a thermodynamic property which is the Krichevskii parameter and secondly to a thermophysical one which is the sublimation pressure. First parameter is considered as a governor of thermodynamic properties in binary dilute mixtures near the solvent's critical point and can be calculated from some rigorous relationships and in this paper a review and a new way for its estimation are presented based on consistency of solid's solubility data in supercritical fluids and dilute solution theory. Second parameter is considered as the predominant influencer on solubility in supercritical fluids and unavailability of its experimental values presents an obstacle to thermodynamic modeling of solubility data. For this reason and as a second step, in this paper we present a new manner for its estimation. Obtained results are relevant, very promising for each considered property and the methodology can be applied for other solutes with more complex structures as Pharmaceuticals (antibiotics, drugs, anti-inflammatories …), polycyclic aromatic hydrocarbons (PAHC) and dyestuffs. 相似文献
9.
Wiebke Saal Nicole Wyttenbach Jochem Alsenz 《Pharmaceutical development and technology》2018,23(2):211-215
Self-aggregation of drugs is since many years an important topic in the pharmaceutical sciences. Drugs can aggregate similar to surfactants and thereby exhibit a critical micelle concentration (CMC). The present work focused on amphiphilic drug bases and it was aimed to predict log(CMC) based on chemical structure alone. A dataset of 35 compounds was gathered mostly form the literature and complemented with own measurements based on ultrasonic resonator technology. The hydrophilic–lipophilic balance (HLB) values of the protonated bases were calculated and provided a range of 22.9–27.4. Based on a hypothesis from surfactant sciences, it was tried to predict log(CMC) with connectivity and shape indices as well as molecular dipole moment. A fairly good model was obtained using the Randix index (RI), 3?D Wiener number (WN) and molecular dipole moment (DM) (R2?=?0.824). Interestingly, a simple linear regression of log(CMC) with the Randic index alone, resulted in an acceptable model (R2?=?0.755). The present work should help with early identification of drug bases that exhibit surfactant-like behavior and an estimation of log(CMC) values is proposed. An improved understanding of drug aggregation and prediction of log(CMC) helps to better cope with physical consequences like, for example, “anomalous” drug solubility in drug discovery and development. 相似文献
10.
The poor solubility and low dissolution rate in gastro-intestinal fluid, especially for class-II drugs according to Biopharmaceutics Classification System (BCS) the bioavailability enhanced by increasing the solubility and dissolution rate. A novel melt sonocrystallization technique of particle engineering to enhance solubility as well as dissolution of hydrophobic drug and to study its effect on crystal properties of drug. The present study leads to use investigate solubility of melt sonocrystallization technique to modify the undesirable properties of Rosiglitazone is antidiabetic drug in thiozolidione category with (BCS II) to forms agglomerates with number of shallow circular pits on the surface leads to increase solubility. Melt sonocrystallization process was developed for Rosiglitazone in which Rosiglitazone melt was poured in deionized water and simultaneously subjected to ultrasonic energy for 20 min at amplitude 80 %. The product obtained was evaluated using scanning electron microscopy, differential scanning calorimetry, X-ray powder diffractometry (XPRD), Fourier transformed infrared spectroscopy (FTIR), solubility and dissolution rate. The irregular agglomerates with porous surface were obtained having different crystal habit which increases solubility and dissolution rate. FTIR shows thermal behavior of untreated Rosiglitazone and treated Rosiglitazone have no significant difference low intensity peaks in XPRD of treated Rosiglitazone were noticed crystals habit changes and lattice defects during processing have causes favorable changes in the physicochemical properties of Rosiglitazone. The use of melt sonocrystallization technique is promising technique that may affords powder with improved flow as well as improved solubility and dissolution. 相似文献