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Microstructure, Content and in vitro Release of Brucine and Strychnine in Strychnos Nux-Vomica Powder with Different Particle Sizes 被引量:4
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作者 倪力军 赵雯雯 +1 位作者 张立国 王南南 《Transactions of Tianjin University》 EI CAS 2014年第6期444-450,共7页
To explore the effect of particle size on the quality uniformity and in vitro release performance of Strychnos nux-vomica powder, seven samples of Strychnos nux-vomica powder with different particle sizes were prepare... To explore the effect of particle size on the quality uniformity and in vitro release performance of Strychnos nux-vomica powder, seven samples of Strychnos nux-vomica powder with different particle sizes were prepared.Microstructures and particle sizes were analyzed, and high performance liquid chromatography(HPLC) was used to test the contents and in vitro release performances of brucine and strychnine in the samples. Results showed that the contents and the in vitro release rates of brucine(or strychnine) in different samples were different since there are different proportions of endosperms to epidermal cells in Strychnos nux-vomica powder with different particle sizes. Brucine and strychnine in each sample were promptly released in the first ten minutes and their cumulative release rates were higher than 70% after ten minutes. Eighty minutes later, the cumulative release rate tended to be a constant. Considering the quality uniformity and safety of Strychnos nux-vomica powder used as traditional Chinese medicine, it would be better to control the particle size of Strychnos nux-vomica powder between 100 and 140 mesh in which the maximum cumulative release rate in vitro of brucine and strychnine can be relatively low within this range. 展开更多
关键词 strychnos nux-vomica BRUCinE STRYCHNinE particle size quality UNIFORMITY in vitro release
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The effect of enzymes on release of trace elements in feedstuffs based on in vitro digestion model for monogastric livestock 被引量:2
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作者 Xiaonan Yu Jianan Han +2 位作者 Haiyun Li Yiwei Zhang Jie Feng 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第1期231-238,共8页
Background: This experiment was conducted to study the effect of different feed enzymes(phytase,xylanase,β-glucanase) on release rate of trace elements(Fe,Cu,Mn and Zn) in 6 commonly used feedstuffs(corn,wheat,barley... Background: This experiment was conducted to study the effect of different feed enzymes(phytase,xylanase,β-glucanase) on release rate of trace elements(Fe,Cu,Mn and Zn) in 6 commonly used feedstuffs(corn,wheat,barley,soybean meal,wheat bran,wheat middlings) by using an in vitro model,simulating the digestive processes in stomach for 2 h and then in small intestine for 6 h at 39 °C.Results: Phytase raised(P < 0.05) the release rate of Cu and Zn in corn,Cu,Zn and Mn in wheat,Cu in barley,Cu,Zn and Mn in soybean meal,Zn,Fe in wheat bran and Zn,Fe,Mn in wheat middlings.The release rate of various trace elements in feedstuffs was increased after xylanase addition.Compared with the control group,the release rate of soluble Cu in corn,wheat,barley and soybean meal,soluble Zn in corn,wheat and wheat middlings and soluble of Mn in corn,wheat,barley and wheat bran increased(P < 0.05) after xylanase treatment.After the treatment of β-glucanase,the release rate of soluble Cu in corn,wheat and wheat bran,soluble Fe in barley,soybean meal and wheat bran and soluble Mn in corn and wheat bran all increased(P < 0.05) compared with the control group.In each feedstuff,after corresponding enzyme treatment,the contents of phytic acid,xylan and β-glucan were significantly lower than those of the control group(P < 0.05).Conclusions: Results showed that bound trace elements in feedstuffs can be released by feed enzymes.It may be necessary to take the trace elements in feedstuffs into account in the actual feed preparation including feed enzymes. 展开更多
关键词 FEEDSTUFFS Feed ENZYMES in vitro MODEL release rate Trace elements
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Fabrication, characterization, in vitro drug release and glucose uptake activity of 14-deoxy,11, 12-didehydroandrographolide loaded polycaprolactone nanoparticles 被引量:1
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作者 Nagalakshmi Kamaraj Pooja Yashwanthi Rajaguru +1 位作者 Praveen kumar Issac Sujatha Sundaresan 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2017年第4期353-362,共10页
Biodegradable polymer based novel drug delivery systems brought a considerable attention in enhancing the therapeutic efficacy and bioavailability of various drugs. 14-deoxy 11, 12-didehydro andrographolide(poorly wat... Biodegradable polymer based novel drug delivery systems brought a considerable attention in enhancing the therapeutic efficacy and bioavailability of various drugs. 14-deoxy 11, 12-didehydro andrographolide(poorly water soluble compound) loaded polycaprolactone(nanoDDA) was synthesized using the solvent evaporation technique. Nano-DDA was characterized by scanning electron microscopy(SEM) and dynamic light scattering(DLS) studies. Fourier Transform InfraRed Spectroscopy(FTIR) was used to investigate the structural interaction between the drug and the polymer. Functional characterization of the formulation was determined using drug content, cellular uptake and in vitro drug release. 2-deoxy-D-[1-~3H] glucose uptake assay was carried out to assess the antidiabetic potential of nano-DDA in L6 myotubes.The nano-DDA displayed spherical shape with a smooth surface(252.898 nm diameter), zeta potential, encapsulation and loading efficiencies of -38.9 mV, 91.98 ± 0.13% and 15.09 ± 0.18% respectively. No structural alteration between the drug and the polymer was evidenced(FTIR analysis). Confocal microscopy studies with rhodamine 123 loaded polycaprolactone nanoparticles(Rh123-PCL NPs) revealed the internalization of Rh123-PCL NPs in a time dependent manner in L6 myoblasts. A dose dependent increase in glucose uptake was observed for nano-DDA with a maximal uptake of 108.54 ± 1.42% at 100 nM on L6 myotubes, thereby proving its anti-diabetic efficacy. A biphasic pattern of in vitro drug release demonstrated an initial burst release at 24 h followed by a sustained release for up to 11 days. To conclude,our results revealed that nano-DDA formulation can be a potent candidate for antidiabetic drug delivery. 展开更多
关键词 NANOENCAPSULATION POLYCAPROLACTONE 14-deoxy 11 12-didehydro ANDROGRAPHOLIDE Glucose UPTAKE in vitro drug release Cellular UPTAKE
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Release of Nestorone from Biodegradable Rods System in vitro
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作者 曹成波 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第1期4-7,共4页
To study the controlled effect of poly (lactic acid) (PLA), poly lactic-coglycolic (PLGA) and ethylenediamine (EDA)-maleic anhydride (MAH) modified PLA (EMPLA) for in vitro release of nestorone, rods were ... To study the controlled effect of poly (lactic acid) (PLA), poly lactic-coglycolic (PLGA) and ethylenediamine (EDA)-maleic anhydride (MAH) modified PLA (EMPLA) for in vitro release of nestorone, rods were prepared using the solvent evaporation method. Amount of drug release in vitro was determined by UV spectrophotometry. Effects of rods diameter, the molecular weight of PLA, the drug percentage and the hydrophilicity of polymers on the release of biodegradable nestorone rods in vitro were investigated. It is indicated that the controlled effect of the biodegradable rods for the release of nestorone in vitro is good. The amount of drug released every week from rods in different diameter is similar to one another. The amount of drug released every week and the accumulative drug released during 12 week were almost in direct proportion with the drug percentage of the rods. The amount of drug released every week is increased as the decreasing of PLA molecular weight. As the hydrophlicity of polymer is improved, the rate of drug release every week is accelerated. The studies show that the plausibility of controlled release of nestorone from PLA, PLGA and EMPLA rods imply the possibility of their application as a controlled delivery system for nestorone. The results show that the greater the molecular weight of PLA is, the slower its degradation is and the slower the drug released; the greater the percentage of nestorone is, the more quickly the drug release. An increase of the hydrophilicity of the polymers will increase their degradation rate and leads to a fast drug release. Anyhow, these rods systems should be further evaluated in vivo. 展开更多
关键词 nestorone PLA PLGA EMPLA RODS in vitro release
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FACTORS AFFECT THE RELEASE OF PSEUDOEPHDRINE HYDROCHLORIDE FROM THE UNCOATED CATION EXCHANGE RESIN-BASED DRUG DELIVERY SYSTEM IN VITRO
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作者 LIZhenhua PIHongqiong 《Chinese Journal of Reactive Polymers》 2001年第1期8-14,共7页
In this paper, it was investigated that the effect of parameters such as the ionic strength, pH, counter-ion type of release medium, particle size, and cross linkage of cation exchange resin on the release of model dr... In this paper, it was investigated that the effect of parameters such as the ionic strength, pH, counter-ion type of release medium, particle size, and cross linkage of cation exchange resin on the release of model drug pseudoephedrine hydrochloride (PE) from uncoated drug-resin complex. The drug-resin complex was prepared by the reaction of PE with strongly acidic cation exchange resin (001×4, 001×7, 001×14). The result showed that the loading of PE increased with the increase of temperatures. The release of PE from drug-resin complex at 37℃ was monitored in vitro. From the experiments, it was found that the release rate of PE depends on the pH, composition of the releasing media, increased at lower pH media or with increase of ionic strength of media. Moreover, the release rate of PE was inversely proportional to the cross-linkage and particle size of the cation exchange resin. 展开更多
关键词 阳离子交换树脂 假麻黄碱 药输送系统
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A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury
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作者 Qi Liu Jianye Xie +5 位作者 Runxue Zhou Jin Deng Weihong Nie Shuwei Sun Haiping Wang Chunying Shi 《Neural Regeneration Research》 SCIE CAS 2025年第2期503-517,共15页
Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug deliv... Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury. 展开更多
关键词 angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 NEUROPROTECTION self-assembling nanofiber hydrogel
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Preparation and in vitro Studies of Stealth PEGylated PLGA Nanoparticles as Carriers for Arsenic Trioxide 被引量:8
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作者 王志清 刘卫 +1 位作者 徐辉碧 杨祥良 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第6期795-801,共7页
学习是准备砷三氧化物(ATO ) 的这的目的装载了秘密 PEGylated PLGA nanoparticles (PEG-PLGA-NPs ) 并且为 ATO 作为药搬运人估计 PEG-PLGA-NPs 的优点交货。PEG-PLGA 共聚物与 methoxypolyethyleneglycol 被综合(Mw = 5000 ) ,由戒... 学习是准备砷三氧化物(ATO ) 的这的目的装载了秘密 PEGylated PLGA nanoparticles (PEG-PLGA-NPs ) 并且为 ATO 作为药搬运人估计 PEG-PLGA-NPs 的优点交货。PEG-PLGA 共聚物与 methoxypolyethyleneglycol 被综合(Mw = 5000 ) ,由戒指洞聚合方法的 D, L 减水乳酸,和 glycolide。非结晶的 ATO 被转变成立方的水晶形式在器官的溶剂增加它的溶解度。装载 ATO 的 PEG-PLGA-NPs 被修改自发的乳化溶剂散开(SESD ) 准备方法,和影响 nanoparticles 的特征的主要试验性的因素被调查,到优化准备。由吞噬细胞从吞噬作用证实 PEG-PLGA-NPs 的逃跑,鼠科的腹巨噬细胞(MPM ) 标记玫瑰精 B 举起的 PEG-PLGA-NPs 被流动 cytometry 分析。结果证明 PEG-PLGA-NPs 的物理化学的特征被 emulsifiers,聚合物集中,和药集中的类型和集中影响。装载 ATO 的 PEG-PLGA-NPs 与 120.8nm 的粒子尺寸,希腊语的第六个字母潜力 - 10.73mV, 73.6% 的封装效率,和 1.36% 装载的药,在最佳的条件下面被准备。传播电子显微镜学(TEM ) 的图象显示优化 nanoparticles 是近球形的并且没有聚集或粘附。在 vitro 的版本实验证明从因而展出的 PEG-PLGA-NPs 的 ATO 版本为超过 26d 支撑了版本,它根据 Higuchi 方程。由 MPM 的 PEG-PLGA-NPs 的举起被发现与 PLGA-NPs 相比显著地减少。试验性的结果证明 PEG-PLGA-NPs 是为 ATO 的潜在的 nano 药交货搬运人。 展开更多
关键词 砒霜 开环聚合 吞噬细胞 体外药物缓释 自发乳化溶解扩散法 高分子聚乙二醇
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Preparation, optimization and in vitro–in vivo investigation for capsules of the choline salt of febuxostat
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作者 Xuemei Han Wanpeng Qi +3 位作者 Wenxiang Dong Mengran Guo Panqin Ma Jing Wang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2016年第6期715-721,共7页
The objective of the present study was to exhibit the enhanced water-solubility and in vivo oral absorption when febuxostat(FXT) became the salt formation of choline. The formation of the choline salt of febuxostat wa... The objective of the present study was to exhibit the enhanced water-solubility and in vivo oral absorption when febuxostat(FXT) became the salt formation of choline. The formation of the choline salt of febuxostat was confirmed by X-ray powder diffraction, infrared spectroscopy analysis and differential scanning calorimetry. The direct filling method was used to develop a capsule formulation. Cellactose 80 was used as the filler due to its good fluidity, while cross-linked polyvinylpyrrolidone(PVPP) and magnesium stearate(MS) were used as the disintegrant and lubricant, respectively. Then the in vitro release of the formulation was carried out in five different dissolution media including HCl solution(pH 1.2),acetate buffer(pH 4.5), phosphate buffer(pH 6.8 and pH 7.2) and water. Evident improvement of release for choline febuxostat(CXT) was presented in water while the dissolution degree was decreased for CXT in the medium of phosphate buffer(pH 6.8) in comparison with FXT. Furthermore, the pharmacokinetics of CXT was studied in rats using UPLC-MS/MS compared with FXT. The data acquired illustrated that AUC0-24 h of CXT and FXT were22,245.96 ± 7342.92 μg·h/l and 12,249.70 ± 2024.04 μg·h/l, respectively. The relative bioavailability of CXT to FXT was about 181.6% and the P value of AUC0-24 h was less than 0.05. It showed significant difference between the two drugs after oral administration. In conclusion, the water-solubility and oral bioavailability were both improved remarkably for the choline salt of febuxostat and choline salinization was proved an effective way to increase the in vivo absorption for FXT. 展开更多
关键词 CHOLinE FEBUXOSTAT Characterization PREPARATION in vitro release BIOAVAILABILITY
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Studies on the in Vitro Dissolution of Insoluble Volatile Drug from Su-Anxin Nasal Inhalant and Its Correlation on the Nose Steady Self-Controllable Expiration and Inspiration at Night
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作者 Xiaodong Li Guoxiang Xie +1 位作者 Suyun Li Chao Hou 《Pharmacology & Pharmacy》 2011年第2期67-72,共6页
In the paper, the in vitro dissolution of borneol in 12 hours from 6 batches of optimized inhalant samples were investigated. As a new dosage form, the in vitro release apparatus of nasal inhalant was invented and a p... In the paper, the in vitro dissolution of borneol in 12 hours from 6 batches of optimized inhalant samples were investigated. As a new dosage form, the in vitro release apparatus of nasal inhalant was invented and a pushing bump was used according to the simulation of the nose expiration and inspiration. Based on the data of r2 in the profile and similar factor f2 from 6 linear release tendencies, a good controlled release and a zero order tendency were observed. It can be suggested that there is a good correlation between the in vitro controlled release and the nose steady self-controllable expiration and inspiration, which will contribute to the trend of insoluble volatile drug controlled release and the effect of quick absorption in nasal pulmonary delivery to cure severe or acute cardiovascular or lung diseases at patients' sleeping, such as angina or breathing obstruction. Also, it was concluded that the prescription composed of insoluble volatile drugs can be prepared to be nasal inhalant from which drugs can be absorbed through nose steady self-controllable inspiration to the lung then into the blood and have a great effectiveness improvement of bioavailability at night timing drug delivery system. 展开更多
关键词 Su-Anxin NASAL inHALANTS inSOLUBLE VOLATILE Drugs Timing DRUG Delivery System in vitro Dissolution Controlled release
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PLGA nanoparticle encapsulated paclitaxol for sustained release and its anticancer effect for HeLa cells in vitro
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作者 Hong Yang, Kai Li, Zhonghua Liu, Zhenglong Ren, Yiyao Liu , Department of Biophysics, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, P.R.China 《生物物理学报》 CAS CSCD 北大核心 2009年第S1期298-299,共2页
Poly (D,L-lactide-co-glycolide) (PLGA) is a biodegradable and biocompatible polymer material for drug deliver system. The aim of this study is to synthesize drug-loaded
关键词 PLGA nanoparticle encapsulated paclitaxol for sustained release and its anticancer effect for HeLa cells in vitro
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Sustained release donepezil loaded PLGA microspheres for injection:Preparation,in vitro and in vivo study 被引量:4
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作者 Wenjia Guo Peng Quan +2 位作者 Liang Fang Dongmei Cun Mingshi Yang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2015年第5期405-414,共10页
The purpose of this study was to develop a PLGA microspheres-based donepezil(DP)formulation which was expected to sustain release of DP for one week with high encapsulation efficiency(EE).DP derived from donepezil hyd... The purpose of this study was to develop a PLGA microspheres-based donepezil(DP)formulation which was expected to sustain release of DP for one week with high encapsulation efficiency(EE).DP derived from donepezil hydrochloride was encapsulated in PLGA microspheres by the O/W emulsion-solvent evaporation method.The optimized formulation which avoided the crushing of microspheres during the preparation process was characterized in terms of particle size,morphology,drug loading and EE,physical state of DP in the matrix and in vitro and in vivo release behavior.DP microspheres were prepared successfully with average diameter of 30m,drug loading of 15.92±0.31%and EE up to 78.79±2.56%.Scanning electron microscope image showed it has integrated spherical shape with no drug crystal and porous on its surface.Differential scanning calorimetry and X-ray diffraction results suggested DP was in amorphous state or molecularly dispersed in microspheres.The Tg of PLGA was increased with the addition of DP.The release profile in vitro was characterized with slow but continuous release that lasted for about one week and fitted well with first-order model,which suggested the diffusion governing release mechanism.After single-dose administration of DP microspheres via subcutaneous injection in rats,the plasma concentration of DP reached peak concentration at 0.50 d,and then declined gradually,but was still detectable at 15 d.A good correlation between in vitro and in vivo data was obtained.The results suggest the potential use of DP microspheres for treatment of Alzheimer’s disease over long periods. 展开更多
关键词 DONEPEZIL PLGA Sustained release MICROSPHERES in vitro and in vivo correlation
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4D printing of core-shell hydrogel capsules for smart controlled drug release 被引量:3
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作者 Shuo Zu Zhihui Zhang +5 位作者 Qingping Liu Zhenguo Wang Zhengyi Song Yunting Guo Yuanzhu Xin Shuang Zhang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2022年第2期294-304,共11页
Personalized drugs,as well as disease-specific and condition-dependent drug release,have been highly desired in drug delivery systems for effective and safe therapies.Four-dimensional(4 D)printing,as a newly emerging ... Personalized drugs,as well as disease-specific and condition-dependent drug release,have been highly desired in drug delivery systems for effective and safe therapies.Four-dimensional(4 D)printing,as a newly emerging technique to develop drug capsules,displays unique advantages that can autonomously control drug release according to the actual physiological circumstances.Herein,core-shell structured hydrogel capsules were developed using a multimaterial extrusion-based 4 D printing method,which consists of a model drug as the core and UV cross-linked poly(N-isopropylacrylamide)(PNIPAM)hydrogel as the shell.Owing to the lower critical solution temperature(LCST)-induced shrinking/swelling properties,the prepared PNIPAM hydrogel capsules showed temperature-responsive drug release along with the topography changes in the cross-linked PNIPAM network.The in vitro drug release test confirmed that the PNIPAM hydrogel capsules can autonomously control their drug release behaviors according to changes in ambient temperature.Moreover,the increased shell thickness of these capsules causes an obvious reduction in drug release rate,distinctly indicating that the drug release behavior can be well adjusted by setting the shell thickness of the capsules.The proposed 4 D printing strategy pioneers the paradigm of smart drug release by showing great potential in the smart controlled release of drugs and macromolecular active agents. 展开更多
关键词 4D printing hydrogel capsules Controlled release Poly(N-isopropylacrylamide)(PNIPAM) Personalized drugs
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Synthesis and Drug Release Properties of Thermosensitive Poly(N-vinylacetamide-co-vinylacetate) Hydrogels 被引量:1
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作者 YANG Li-he CHU Hong CHEN Ming-qing HU Na ZHAO Yi-fan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第2期334-338,共5页
Thermosensitive poly[N-vinylacetamide-co-vinylacetate][P(NVA-co-VAc)] hydrogels were prepared via free radical copolymerization from hydrophilic NVA and hydrophobic VAc in the presence of butylenes-bis (N-vinylacet... Thermosensitive poly[N-vinylacetamide-co-vinylacetate][P(NVA-co-VAc)] hydrogels were prepared via free radical copolymerization from hydrophilic NVA and hydrophobic VAc in the presence of butylenes-bis (N-vinylacetamide)(Bis-NVA) as crosslinker. Scanning electron microscopy(SEM) images reveal that the as-prepared hydrogels were of three-dimensional network with irregular cave structure. The prepared hydrogels with more NVA in the feed swelled faster and the swelling ratio of the hydrogels gradually decreased with temperature increasing from 10 °C to 60 °C. The dynamic swelling studies indicate that the swelling process of the hydrogels was controlled by diffusion of water molecules considered as Fickian-controlled case. The adsorption amount of model drug, sodium salicylate(SS) was higher in the hydrogels containing more NVA units, whose corresponding release could reach equilibrium in about 6 h. 展开更多
关键词 Poly(N-vinylacetamide-co-vinylacetate) Therrnosensitive hydrogel Drug release
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Influence of Alternating and Static Magnetic Fields on Drug Release from Hybrid Hydrogels Containing Magnetic Nanoparticles 被引量:2
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作者 Marianna Uva Daniela Pasqui +2 位作者 Lorenzo Mencuccini Serena Fedi Rolando Barbucci 《Journal of Biomaterials and Nanobiotechnology》 2014年第2期116-127,共12页
Hybrid hydrogels of carboxymethylcellulose (CMC), containing two different amounts of CoFe2O4 magnetic nanoparticles (50% and 70% in relation to the quantity of the polymer) as crosslinkers, were prepared. The hybrid ... Hybrid hydrogels of carboxymethylcellulose (CMC), containing two different amounts of CoFe2O4 magnetic nanoparticles (50% and 70% in relation to the quantity of the polymer) as crosslinkers, were prepared. The hybrid hydrogels were chemically and morphologically characterized and their viscoelastic properties and swelling degrees were analyzed. The hydrogels were tested as controlled drug delivery systems by applying one static and two different alternating magnetic fields. The application of the two alternating magnetic fields (AMF) to the hybrid hydrogels induced a higher release of methylene blue (MB), used as a model drug, than without the application of any magnetic field, especially at low frequency (4 Hz) and high magnetic intensity (0.5 T). In contrast, when the hybrid hydrogels were exposed to a static magnetic field (SMF) the release of MB was slowed down. Furthermore the two different amounts of magnetic nanoparticles induce different responses to the magnetic field. The greater number of nanoparticles in the CMC-NP-70 hydrogel leads to the formation of some NPs clusters limiting the drug release;conversely, the CMC-NP-50 hydrogel, containing a lower amount of nanoparticles, shows a higher release of MB vs. time. In conclusion, we were able to get a potential system for modulation of the drug delivery: the release behaviour of hybrid hydrogels can be modulated by applying alternating and static magnetic fields cyclically. A possible explanation for the release mechanism is about the structural modification of the polymeric chains that occurs when the hybrid hydrogels are exposed to the magnetic fields. 展开更多
关键词 MAGNETIC hydrogelS ALTERNATinG MAGNETIC FIELD Static MAGNETIC FIELD Controlled release COBALT FERRITE Nanoparticles
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In vitro Evaluation of Lysozyme-loaded Microspheres in Thermosensitive Methylcellulose-based Hydrogel 被引量:3
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作者 林莹 孙佳丽 +2 位作者 蒋国强 昝佳 丁富新 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第4期566-572,共7页
Long-term injectable microspheres have some inherent disadvantages such as migration of micro- spheres from the original site and the burst effect.In order to avoid these problems,microsphere-loaded thermosen- sitive ... Long-term injectable microspheres have some inherent disadvantages such as migration of micro- spheres from the original site and the burst effect.In order to avoid these problems,microsphere-loaded thermosen- sitive hydrogel system was designed and expected to achieve a zero-order release of biomolecular drugs in relative high initial drug loadings.Lysozyme,an antibacterial protein usually used to reduce prosthetic valve endocarditis, was selected as the model drug.Poly(DL-lactide-co-glycolide)(PLGA)microspheres,prepared by solvent evapo- ration method,were employed to encapsulate lysozyme and dispersed into thermosensitive pre-gel solution con- taining methylcellulose(MC),polyethylene glycol(PEG),sodium citrate(SC),and sodium alginate(SA).The mix- ture could act as a drug reservoir by performing sol-gel transition rapidly if the temperature was raised from room temperature to 37℃.The in vitro release results showed that the burst effect was avoided due to strengthening of diffusion resistance in the gel.The formulation was able to deliver lysozyme for over 30 days in a nearly zero-order release profile with a rate of 32.8μg.d -1 which exhibits its remarkable potential for effective application in long-term drug delivery. 展开更多
关键词 热敏水凝胶 微滴 药物释放 甲基纤维素 溶菌酶
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Preparation and <i>in Vitro</i>Drug Release Evaluation of Once-Daily Metformin Hydrochloride Sustained-Release Tablets 被引量:1
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作者 Ling Zhao Yumeng Wei +4 位作者 Yong Mei Li Yang Yuan You Xufeng Yang Yanhong Jiang 《Pharmacology & Pharmacy》 2012年第4期468-473,共6页
The objective of this study was to develop once-daily metformin hydrochloride sustained-release tablets (MHSRT) and evaluate their in vitro release behavior. MHSRT were prepared by the film coating method. The in vitr... The objective of this study was to develop once-daily metformin hydrochloride sustained-release tablets (MHSRT) and evaluate their in vitro release behavior. MHSRT were prepared by the film coating method. The in vitro drug release rate of MHSRT and the commercial tablets Fortamet? made in the United States of America in water was fitted with zero order kinetic equation, and Ritger-Peppas kinetic equation in 0.1 M HCl and pH 6.8-phosphate buffer, respectively. The similarity factor f2 values of MHSRT in three different dissolution medium were 82, 80 and 74, respectively in comparison with imported Fortamet?, which were all greater than 50. The results of storage-stability showed that MHSRT were stable for at least 6 months under stress condition (40℃ ± 2℃, RH 75% ± 5%). Therefore, in this study, MHSRT were successfully prepared using optimized formulation technologies that meet mass produce. The in vitro release behavior of MHSRT was almost similar to that of imported Fortamet?. 展开更多
关键词 SUSTAinED-release Tablets METFORMin HYDROCHLORIDE in vitro release Rate Similarity Factor Kinetic Model
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Formation of composite hydrogel of carboxymethyl konjac glucomannan/gelatin for sustained release of EGCG 被引量:1
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作者 Lin Wang Ning zhou +1 位作者 Shengxuan Zheng Jie Pang 《Food Science and Human Wellness》 SCIE 2022年第5期1373-1383,共11页
Development of functional bioinspired hydrogels that have good releases control character is necessary for the application of these materials in biomedical engineering.Herein,we report a composite hydrogel prepared fr... Development of functional bioinspired hydrogels that have good releases control character is necessary for the application of these materials in biomedical engineering.Herein,we report a composite hydrogel prepared from several biocompatible carboxymethyl konjac glucomannan(CKGM)/gelatin(G)/tannic acid(TA)functional nano-hydroxyapatite(TA@n-HA),which has good biodegradability and pH sensitivity.The mechanism of interaction between hydrogels was confirmed by Fourier transform infrared spectroscopy,X-ray diffraction,Scanning electron microscopy and Thermogravimetric analysis.The physico-chemical properties of CKGM/G hydrogels have been significantly improved through the incorporation of TA@n-HA within the matrix.Studies in the sustained release of epigallocatechin gallate(EGCG)demonstrated that the TA@n-HA/CKGM/G hydrogels exhibit not only better pH sensitive properties,but also enhanced biocompatibility and encapsulation in comparison to the matrix devoid of TA@n-HA.Consequently,TA@n-HA/CKGM/G hydrogels using EGCG as a drug release model show the potential for drug delivery. 展开更多
关键词 hydrogel Carboxymethyl konjac glucomannan GELATin Tannic acid BIODEGRADATION Sustained release
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Effect of nonionic surfactants in release media on accelerated in-vitro release profile of sirolimus eluting stents with biodegradable polymeric coating 被引量:2
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作者 Ami Raval Pratap Bahadur Ankur Raval 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2018年第1期45-54,共10页
It is a well-known fact that sirolimus(SRL) undergoes degradation process via hydrolysis in aqueous media, leading to incorrect assessment of drug amount and thus release characteristics of formulations.The main objec... It is a well-known fact that sirolimus(SRL) undergoes degradation process via hydrolysis in aqueous media, leading to incorrect assessment of drug amount and thus release characteristics of formulations.The main objective of the present study was to evaluate the effect of nonionic surfactants in media on invitro release profiles for sirolimus eluting stents(SES) coated with biodegradable polymeric matrix.Phosphate buffer and acetate buffer incorporating nonionic surfactants with varying concentrations were examined for adequate solubility and stability(by RP-HPLC). Good sink condition was achieved in phosphate buffer(at pH 4.0) with 1.0% Tween 20, 1.0% Brij 35% and 0.5% Brij 58. Hydrodynamic size(by DLS) and the micelle-water partition coefficient(P) with standard free energy of solubilization(ΔGs°) of drug were evaluated to get some understanding about the solubilization phenomena. About 80% of drug release during the period of 48 h was achieved in optimized drug release media which was 1.0% Tween20 in phosphate buffer pH 4.0. The obtained accelerated SRL release profile in optimized medium correlated well with the real time in-vitro release in phosphate buffer(pH 7.4). Surface morphology changes(by SEM), changes in gravimetric weights and molecular weight change(by GPC) were examined before and after drug release to understand the drug release mechanism which explains that the polymer did not undergo degradation during the drug release. 展开更多
关键词 NONIONIC SURFACTANT in-vitro release STENTS BIODEGRADABLE polymers
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Interpenetrated Chitosan-Poly(Acrylic Acid-Co-Acrylamide) Hydrogels. Synthesis, Characterization and Sustained Protein Release Studies 被引量:1
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作者 Michel Bocourt Povea Waldo Argüelles Monal +3 位作者 Juan Valerio Cauich-Rodríguez Alejando May Pat Nancy Badas Rivero Carlos Peniche Covas 《Materials Sciences and Applications》 2011年第6期509-520,共12页
Interpenetrated polymer networks of chitosan (CHI), polyacrylic acid (PAA) and polyacrylamide (PAM) were prepared by free radical polymerization. These hydrogels were either washed with double distilled water (CHI/PAA... Interpenetrated polymer networks of chitosan (CHI), polyacrylic acid (PAA) and polyacrylamide (PAM) were prepared by free radical polymerization. These hydrogels were either washed with double distilled water (CHI/PAA/PAM) A or hydrolyzed with 1M sodium hydroxide (NaOH), (CHI/PAA/PAM) S. Both types of hydrogels were characterized by infrared spectroscopy, microstructural techniques and compressive mechanical testing. Finally, hydrogels were loaded with bovine serum albumin (BSA) and release followed at different pHs. Infrared spectra analysis showed correspondence between hydrogels and monomer feed compositions. Hydrolyzed hydrogels, had increased water content and pH swelling dependence. Compression modulus of swelled hydrolyzed hydrogels decreased with increasing equilibrium water content. Higher BSA loadings were achieved on hydrolyzed hydrogels due to their high water content and porosity. Protein release from hydrogels was low (≤ 20% after 10 hours) at pH 1.2, but sustained release was observed at pH 6.8 and 7.4. The integrity of the protein released at 6.8 and 7.4 by hydrolyzed hydrogels was unaffected. The hydrogles showed no cytotoxic effects on human skin dermal fibroblasts as determined by MTT assay except for two compositions of (CHI/PAA/PAM) A samples, which after seven days presented a viability lower than 80% respect to the control. 展开更多
关键词 hydrogelS Controlled release Protein POLYACRYLAMIDE interpenetrated Polymer
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5-Fluorouracil loaded guar gum microspheres for colon delivery: preparation, characterization and in vitro release 被引量:1
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作者 KAUSHIK Dinesh SARDANA Satish MISHRA DN 《药学学报》 CAS CSCD 北大核心 2009年第11期1278-1284,共7页
The present investigation is aimed to develop a new formulation containing chemically crosslinked guar gum microspheres loaded with 5-fluorouracil for targeting colorectal cancer. The emulsification polymerization met... The present investigation is aimed to develop a new formulation containing chemically crosslinked guar gum microspheres loaded with 5-fluorouracil for targeting colorectal cancer. The emulsification polymerization method involving the dispersion of aqueous phase of guar gum in castor oil was used to prepare spherical microspheres. Various processing parameters were studied in order to optimize the formulation. Particle size and surface morphology of the microspheres were determined using optical microscopy and scanning electron microscopy. The in vitro drug release studies performed in simulated gastric fluid (SGF) for 2 h followed by intestinal fluid for 3 h, revealed the retention of the drug inside the microspheres from which only (15.27 ± 0.56) % of the drug was released in 5 h. In vitro release rate studies were also carried out in simulated colonic fluid (SCF) in the presence of rat caecal contents, which showed improved drug release. The drug release from the formulation was found to be (41.6 ± 3.5) % with 2% (w/v) caecal matter in 24 h as compared to control study where (25.2 ± 3.5) % of drug was released. The drug release from the formulation with 2% and 4% rat caecal contents medium after 2 days of enzyme induction was found to be (56.3 ± 4.1) % and (78.9 ± 2.8) % in 24 h respectively. Similarly, (61.3 ± 5.4) % and (90.2 ± 2.9) % drug was released respectively with 2% and 4% rat caecal matter after 4 days of enzyme induction and (72.1 ± 2.9) % and (90.2 ± 3.2) % after 6 days of enzyme induction. In this way, 5-fluorouracil loaded guar gum microspheres have shown promising results in the management of colorectal cancer, warranting thorough in vivo study for scale up technology. 展开更多
关键词 制剂学 药学 氟尿嘧啶 临床
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