共查询到20条相似文献,搜索用时 421 毫秒
1.
Shashank Jain Niketkumar Patel Parshotam Madan Senshang Lin 《Drug development and industrial pharmacy》2016,42(8):1315-1324
Objective: To select a suitable ethosome-loaded Carbopol hydrogel formulation, specifically tailored for transdermal application that exhibits (i) plastic flow with yield stress of approximately 50–80?Pa at low polymer concentration, (ii) relatively frequency independent elastic (G′) and viscous (G″) properties and (iii) thermal stability.Methods: Carbopol (C71, C934, C941, C971 or C974) hydrogels were prepared by dispersing Carbopol in distilled water followed neutralization by sodium hydroxide. The effects of Carbopol grade, Carbopol concentration, ethosome addition and temperature on flow (yield stress and viscosity) and viscoelastic (G′ and G″) properties of Carbopol hydrogel were evaluated. Based on the aforementioned rheological properties evaluated, suitable ethosome-loaded Carbopol hydrogel was selected. In-vitro permeation studies of diclofenac using rat skin were further conducted on ethosome-loaded Carbopol hydrogel along with diclofenac-loaded ethosomal formulation as control.Results: Based on preliminary screening, C934, C971 and C974 grades were selected and further evaluated for flow and viscoelastic properties. It was observed that ethosome-loaded C974 hydrogel at concentration of 0.50 and 0.75% w/w, respectively, demonstrated acceptable plastic flow with distinct yield stress and a frequency independent G′ and G″. Furthermore, the flow and viscoelastic properties were maintained at the 4, 25 and 32?°C. The results from in vitro skin permeation studies indicate that ethosome-loaded C974 hydrogel at 0.5% w/w polymer concentration exhibited similar skin permeation as that of ethosomal formulation.Conclusion: The results indicate that suitable rheological properties of C974 could facilitate in achieving desired skin permeation of diclofenac while acting as an efficient carrier system for ethosomal vesicles. 相似文献
2.
Wiwat Pichayakorn Prapaporn Boonme 《Materials science & engineering. C, Materials for biological applications》2013,33(3):1197-1202
The aims of this study were to find the optimal formulation for the preparation of metronidazole-loaded chitosan microparticles (MTZ-MPs) via an emulsion cross-linking process, and to compare the in vitro release of MTZ from hydrogels and films containing the drug in forms of MTZ-MPs and raw powders. The effects of emulsifier type and concentration, amount of cross-linking agent, cross-linking time, drug:chitosan ratio, form of drug adding and washing method on the properties of the MTZ-MPs were investigated. The results indicated that the optimal conditions for round and free-flowing MTZ-MPs with a high percentage of entrapped drug and preferable release profile were 1% of Span80 in soybean oil, 5% of glutaraldehyde based on chitosan solution, 30 min of cross-linking time, 1:1 drug:chitosan ratio, drug adding in form of ethanol solution and washing with hexane only. MTZ-MPs prepared from the optimal formulation were incorporated in mucoadhesive hydrogel and film. The release profiles of the drug from hydrogel and film containing MTZ-MPs were in prolong pattern compared with those containing drug powders. However, the hydrogels exhibited higher preferable pattern of release profile than the films. Therefore, the hydrogel containing MTZ-MPs was possible to be further clinically investigated for peridontitis treatment. 相似文献
3.
Nadia M. Morsi Nouran Osama Eladawy Abdelfattah A. Abdelkhalek 《Drug development and industrial pharmacy》2019,45(5):787-804
Hydrogels forming in-situ have gained great attention in the area of bone tissue engineering recently, they were also showed to be a good and less invasive alternative to surgically applied ones. The primal focus of this study was to prepare chitosan-glycerol phosphate thermosensitive hydrogel formed in-situ and loaded with risedronate (bone resorption inhibitor) in an easy way with no requirement of complicated processes or large number of equipment. Then we investigated its effectiveness for bone regeneration. In-situ forming hydrogels were prepared using chitosan cross-linked with glycerol phosphate and loaded with risedronate and nano-hydroxyapatite as bone cement. The prepared hydrogels were characterized by analyzing their gelation time at 37?°C, % porosity, swelling index, in-vitro degradation, rheological properties, and in-vitro drug release. Results showed that the in-situ hydrogels prepared using 2.5% (w/v) chitosan cross-linked with 50% (w/v) glycerol phosphate in the ratio (9:1, v/v) reinforced with 20?mg/mL and nano-hydroxyapatite possessed the most sustained drug release profile. This optimized formulation was further evaluated using DSC and FTIR studies, in addition to their morphological properties using scanning electron microscopy. The effect on Saos-2 cell line viability was evaluated also using MTT assay on the optimized hydrogel formulation in addition to their action on cell proliferation using fluorescence microscope. Moreover, calcium deposition on the hydrogel and alkaline phosphatase activity were evaluated. Risedronate-nano-hydroxyapatite loaded hydrogels significantly enhanced the Saos-2 cell proliferation in addition to enhanced alkaline phosphatase activity and calcium deposition. Such results suggest that risedronate-nano-hydroxyapatite loaded hydrogels present great biocompatibility for bone regeneration. Proliferation of cells, as well as deposition of mineral on the hydrogel, was an evidence of the biocompatible nature of the hydrogel. This hydrogel formed in-situ present a good less invasive alternative for bone tissue engineering. 相似文献
4.
Lina Altomare Andrea Cochis Andrea Carletta Lia Rimondini Silvia Farè 《Journal of materials science. Materials in medicine》2016,27(5):95
Methylcellulose (MC), a water-soluble polymer derived from cellulose, was investigated as a possible temporary substrate having thermo-responsive properties favorable for cell culturing. MC-based hydrogels were prepared by a dispersion technique, mixing MC powder (2, 4, 6, 8, 10, 12 % w/v) with selected salts (sodium sulphate, Na2SO4), sodium phosphate, calcium chloride, or phosphate buffered saline, to evaluate the influence of different compositions on the thermo-responsive behavior. The inversion test was used to determine the gelation temperatures of the different hydrogel compositions; thermo-mechanical properties and thermo-reversibility of the MC hydrogels were investigated by rheological analysis. Gelation temperatures and rheological behavior depended on the MC concentration and type and concentration of salt used in hydrogel preparation. In vitro cytotoxicity tests, performed using L929 mouse fibroblasts, showed no toxic release from all the tested hydrogels. Among the investigated compositions, the hydrogel composed of 8 % w/v MC with 0.05 M Na2SO4 had a thermo-reversibility temperature at 37 °C. For that reason, this formulation was thus considered to verify the possibility of inducing in vitro spontaneous detachment of cells previously seeded on the hydrogel surface. A continuous cell layer (cell sheet) was allowed to grow and then detached from the hydrogel surface without the use of enzymes, thanks to the thermo-responsive behavior of the MC hydrogel. Immunofluorescence observation confirmed that the detached cell sheet was composed of closely interacting cells. 相似文献
5.
Design and optimization of thermosensitive nanoemulsion hydrogel for sustained-release of praziquantel 总被引:1,自引:0,他引:1
Zhaotong Cong Xue Peng Bei Wei Yu Wang Jincheng Li 《Drug development and industrial pharmacy》2017,43(4):558-573
Objective: This work aimed to develop an alternative sustained-release thermosensitive praziquantel-loaded nanoemulsion (PZQ-NE) hydrogel for better schistosomiasis treatment.Significance: PZQ-NE-dispersed chitosan/glycerol 2-phosphate disodium/HPMC (NE/CS/β-GP/HMPC) hydrogel was successfully prepared to improve bioavailability of PZQ.Methods: Solubility tests and pseudo-ternary phase diagrams were applied to screen optimal oils, surfactants and co-surfactants of NE. The hydrogels were characterized for gelling time, surface exudates, rheological properties and in vitro drug release. Formulation optimization of NE/CS/β-GP/HMPC hydrogel was conducted by Box–Behnken experimental design combined with response surface methodology. In vitro cytotoxicity of hydrogel was studied by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide method. The sustained-release property of PZQ in NE and optimized hydrogel was evaluated by pharmacokinetic study in rabbits.Results: The formulation of PZQ-NE consisted of mass ratio of 12.5% capryol 90 containing PZQ (160?mg/g), 40% cremophor RH 40/tween 20 and transcutol HP (S/CoS?=?2:1), 47.5% deionized water. PZQ releasing from NE/CS/β-GP/HMPC hydrogels was best fitted to Higuchi model and governed by diffusion. Rheological investigation evidenced the themosensitive gelation of different hydrogel systems and their gel-like character at 37?°C. The optimized hydrogel formulation consisted of HPMC solution (103.69?mg/g), 3.03% (w/v) chitosan and 14.1% (w/v) β-GP showed no cytotoxicity when the addition of NE was no more than 100?mg/g. Pharmacokinetic parameters indicated that NE/CS/β-GP/HMPC hydrogel can significantly slow down drug elimination, prolong mean residence time and improve bioavailability of PZQ.Conclusions: NE/CS/β-GP/HMPC hydrogel possessed sustained-release property and could be an alternative antischistosomal drug delivery system with improved therapeutic effect. 相似文献
6.
Szu-Hsien Chen Ching-Ting Tsao Chih-Hao Chang Yi-Ting Lai Ming-Fung Wu Ching-Nan Chuang Hung-Chia Chou Chih-Kuang Wang Kuo-Haung Hsieh 《Materials science & engineering. C, Materials for biological applications》2013,33(5):2584-2594
Wound dressings of chitosan are biocompatible, biodegradable, antibacterial and hemostatic biomaterials. However, applications for chitosan are limited due to its poor mechanical properties. Here, we conducted an in vivo mouse angiogenesis study on reinforced poly(ethylene glycol) (PEG)-chitosan (RPC) hydrogels. RPC hydrogels were formed by cross-linking chitosan with PEGs of different molecular weights at various PEG to chitosan ratios in our previous paper. These dressings can keep the wound moist, had good gas exchange capacity, and was capable of absorbing or removing the wound exudate. We examined the ability of these RPC hydrogels and neat chitosan to heal small cuts and full-thickness skin defects on the backs of male Balb/c mice. Histological examination revealed that chitosan suppressed the infiltration of inflammatory cells and accelerated fibroblast proliferation, while PEG enhanced epithelial migration. The RPC hydrogels promoted wound healing in the small cuts and full layer wounds. The optimal RPC hydrogel had a swelling ratio of 100% and a water vapor transmission rate (WVTR) of about 2000 g/m2/day. In addition, they possess good mechanical property and appropriate degradation rates. Thus, the optimal RPC hydrogel formulation functioned effectively as a wound dressing and promoted wound healing. 相似文献
7.
Junling Wang Yuan Yuan Changsheng Liu Di Zhu Xi Shen Baican Yang 《Journal of materials science. Materials in medicine》2009,20(10):2075-2084
To reduce the toxicity and enhance the therapeutic efficacy of brucine, a traditional Chinese medicine for relieving arthritic
and traumatic pain, in this study, a novel brucine-loaded liposomal hydrogel (BLH) formulation, suitable for topical application,
was developed. Spherical liposomes composed of lecithin and cholesterol, with brucine, was prepared by a modified ethanol-dripping
method. High percentage (over 80%) of encapsulated brucine in liposomes was obtained. Topical liposomal hydrogel formulations
were prepared by further incorporation of the prepared liposomes into structured carbopol 940 hydrogels with the concentration
of carbopol 1.0%, the ratio of glycerol to carbopol 8:1 and the brucine content 0.1%. The liposomal hydrogel formulations
provided an obvious promotion for skin permeation of bruicne while for the free brucine in hydrogels (BH), there was no detectable
drug permeation through the skin. The safety evaluation showed that the prepared BLH were no irritation to both the broken
and integrity skin. Pharmacodynamic evaluation revealed that the BLH showed a better therapeutic efficacy than that of the
BH. So, it can be concluded that the BLH developed here could represent a safe, effective and promising transdermal formulation
for local treatment of analgesic and anti-inflammatory disease. 相似文献
8.
Wei-Fang LIU Chuan-Zhen KANG Ming KONG Yang LI Jing SU An YI Xiao-Jie CHENG Xi-Guang CHEN 《材料科学前沿(英文版)》2012,6(3):250
Chitosan/α, β-glycerophosphate (CS/α, β-GP) thermo-sensitive hydrogels presented flowable solution state at low temperature and semisolid hydrogel when the ambient temperature increased. In this research, different concentrations of metronidazole encapsulated, CS and α, β-GP, as well as different acid solvents, were chosen to evaluate their influences on the drug release behaviors from CS/α, β-GP hydrogels. It was found that there was a sustaining release during the first 3 h followed by a plateau. SEM images showed that drugs were located both on the surface and in the interior of hydrogels. The optimal preparation conditions of this hydrogel for drug release were as follows: 1.8% (w/v) CS in HAc solvent, 5.6% (w/v) α, β-GP and 5 g/L metronidazole encapsulation. Cytotoxicity evaluation found no toxic effect. In order to control the release rate, 2.5 g/L chitosan microspheres with spherical shape and smooth surface were incorporated, and it was found that the initial release process was alleviated, while drug concentration had no obvious effect on the release rate. It could be concluded that the metronidzole release behaviors could be optimized according to practical applications. 相似文献
9.
Fabrication of chitosan/poly(ε-caprolactone) composite hydrogels for tissue engineering applications
Zhong X Ji C Chan AK Kazarian SG Ruys A Dehghani F 《Journal of materials science. Materials in medicine》2011,22(2):279-288
The aim of this study was to fabricate three-dimensional (3D) porous chitosan/poly(ε-caprolactone) (PCL) hydrogels with improved
mechanical properties for tissue engineering applications. A modified emulsion lyophilisation technique was developed to produce
3D chitosan/PCL hydrogels. The addition of 25 and 50 wt% of PCL into chitosan substantially enhanced the compressive strength
of composite hydrogel 160 and 290%, respectively, compared to pure chitosan hydrogel. The result of ATR–FTIR imaging corroborated
that PCL and chitosan were well mixed and physically co-existed in the composite structures. The composite hydrogels were
constructed of homogenous structure with average pore size of 59.7 ± 14 μm and finer pores with average size of 4.4 ± 2 μm
on the wall of these larger pores. The SEM and confocal laser scanning microscopy images confirmed that fibroblast cells were
attached and proliferated on the 3D structure of these composite hydrogels. The composite hydrogels acquired in this study
possessed homogeneous porous structure with improved mechanical strength and integrity. They may have a high potential for
the production of 3D hydrogels for tissue engineering applications. 相似文献
10.
Takashi Tamura Kozo Takayama Hiroshi Satoh Keiki Tanno Tsuneji Nagai 《Drug development and industrial pharmacy》1997,23(3):285-291
Oil/water-type cyclosporine (CyA) hydrogel ointment was evaluated as a candidate for the percutaneous application of CyA. The physical properties and the permeation profiles of 2% w/w CyA gel ointment were compared with other CyA ointments. All ointments used in this study were prepared with commercially available CyA (Sandimmune) oral solution, unlike the ointment reported in the publication of by Mizoguchi et al. The gel ointment required a surfactant corresponding to 5-7% w/w to obtain fine uniform particles. Mean diameter of oily particles in the gel ointment was 8.75 μm. The permeation of CyA from the ointments was investigated by using the abdominal skin of hairless rats in vitro. The percutaneous permeation of CyA was observed to be influenced by a variety of ointment bases used and by the presence of a stratum corneum which plays a role as the main barrier. In intact skin, the extent of permeation from the gel ointment was almost equivalent to that from Mizoguchi's ointment, which used the raw CyA. No permeation was observed in ointment bases with either white petrolatum or hydrophilic petrolatum, indicating values under the limit of detection (78 ng/ml) of the high-performance liquid chromatographic method used in this study. On the other hand, in stripped skin, differences in flux value of each ointment were shown. Those values increased in the following order: Mizoguchi's ointment, white petrolatum, hydrogel, hydrophilic petrolatum. From these results, hydrogel ointment seemed to be applicable for various skin diseases which respond to CyA. Of the physical properties, spreadability and consistency showed that gel ointment was superior to Mizoguchi's ointment. In stability tests, the gel ointment was stable with regard to particle size and residual CyA for 4 weeks. These results suggested that the oil/water-type CyA hydrogel ointment prepared in a combination with hydrogel and commercially available oral solution was useful for practical hospital preparations, with good physical properties, permeability, and stability. 相似文献
11.
《Materials Letters》2007,61(8-9):1704-1706
In this paper, carbon nanotubes (CNTs) were added into poly(vinyl alcohol) (PVA) hydrogels to modify their mechanical properties. A series of CNT/PVA hybrid hydrogels were prepared by freezing/thawing method. The mechanical and swelling properties of all hybrid hydrogels are better than those of the original PVA hydrogel. Especially, for CNTP-0.5 specimen with 0.5% w/w CNTs, its tensile modulus, tensile strength and strain at break are increased by 78.2%, 94.3% and 12.7%, respectively. And its swelling behavior is different from that of the pure PVA hydrogel. Its final swelling ratios at room temperature and 310 K are increased by 35.7% and 44.9%, respectively. 相似文献
12.
The aim of this study was to develop a pH-sensitive chitosan/polyvinyl pyrrolidone (PVP) based controlled drug release system for clarithromycin. The hydrogels were synthesized by cross-linking chitosan and PVP blend with glutaraldehyde to form a semi-interpenetrating polymer network (semi-IPN). These semi-IPNs were studied for their content uniformity, swelling index (SI), mucoadhesion, wettability, in vitro release and their release kinetics. The hydrogels showed more than 97% content of clarithromycin. These hydrogels showed high swelling and mucoadhesion under acidic conditions. The swelling may be due to the protonation of a primary amino group on chitosan. In acidic condition, chitosan would be ionized, and adhesion could have occurred between the positively charged chitosan and the negatively charged mucus. In the alkaline condition, less swelling and mucoadhesion was noticed. In vitro release study revealed that formulation containing chitosan (2% w/v) and PVP (4% w/v) in the ratio of 21:4 showed complete drug release after 12 h. Release profile showed that all the formulations followed non-Fickian diffusion mechanism. The cross-linking and compatibility of clarithromycin in the formulation was studied by Fourier transform infrared (FTIR) spectroscopic analysis, differential scanning calorimetry (DSC) and powder X-ray diffraction (p-XRD) study, which confirmed proper formation of semi-IPN and stability of clarithromycin in the formulations. The surface morphology of semi-IPN was studied before and after dissolution in simulated gastric fluid (SGF, pH 1.2) which revealed pores formation in membrane after dissolution. The results of study suggest that semi-IPNs of chitosan/PVP are potent candidates for delivery of clarithromycin in acidic environment. 相似文献
13.
Zhu Chen Ming Zhao Kang Liu Yuqing Wan Xudong Li Gang Feng 《Journal of materials science. Materials in medicine》2014,25(8):1903-1913
Traditional chitosan hydrogels were prepared by chemical or physical crosslinker, and both of the two kinds of hydrogels have their merits and demerits. In this study, researchers attempted to prepare one kind of chitosan hydrogel by slightly crosslinker, which could combine the advantages of the two kinds of hydrogels. In this experiment, the crosslinker was formed by a reaction between the isocyanate group of 1,6-diisocyanatohexan and the hydroxyl group of polyethylene glycol-400 (PEG-400), then the crosslinker reacted with the amidine and the hydroxyl group of ethylene glycol chitosan to form the network structure. Physical properties of the hydrogel were tested by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and biodegradation. Biocompatibility was assessed by cell implantation in vitro and the scaffold was used as a cartilage tissue engineering scaffold to repair a defect in rabbit knee joints in vivo. FTIR results show the formation of a covalent bond during thickening of the ethylene glycol chitosan. SEM and degradation experiments showed that the ethylene glycol chitosan hydrogel is a 3-D, porous, and degradable scaffold. The hydrogel contained 2 % ethylene glycol chitosan and 10 μl crosslinker was selected for the biocompatibility experiment in vitro and in vivo. After chondrocytes were cultured in the ethylene glycol chitosan hydrogel scaffold for 1 week cells exhibited clustered growth and had generated extracellular matrix on the scaffold in vitro. The results in vivo showed that hydrogel-chondrocytes promoted the repair of defect in rabbits. Based on these results, it could be concluded that ethylene glycol chitosan hydrogel is a scaffold with excellent physicochemical properties and it is a promising tissue engineering scaffold. 相似文献
14.
Fang Li Qiujie Ba Sumei Niu Yi Guo Yankang Duan Peng Zhao Chao Lin Jing Sun 《Materials science & engineering. C, Materials for biological applications》2012,32(7):2017-2025
In-situ forming hydrogels from thiolated glycol chitosan (GCH-SH) and vinyl sulfone-modified PEG (PL-VS) were designed, prepared and successfully applied as biodegradable, non-toxic bio-scaffolds for chondrocyte culture. The hydrogels could be formed in situ under physiological conditions via Michael-type addition between the GCH-SH and PL-VS at a low polymer concentration of 1–3% (w/v). Gelation times varied from 0.75 to 50 min, depending on the polymer concentration and the arm number of PEG-VS. Moreover, a high arm number and a high polymer concentration may lead to efficient network formation of GCH-SH/PEG-VS hydrogels. These hydrogels were found biodegradable in the presence of lysozyme, a cationic protein in the body, for a long period of time. Rheological studies indicated that these hydrogels generally displayed highly elastic property and had higher mechanical strength than those from thiolated hyaluronic acid/PEG-VS reported previously. SEM observation revealed that these hydrogels possessed well-interconnected microporous morphology. Besides these, the chondrocytes could be incorporated and homogeneously distributed in the hydrogel based on GCH-SH and 4-arm PL-VS. Importantly, after cell culture of 14 days, the chondrocytes in the hydrogel remained viable, as determined by a live–dead assay, and the cells kept their round chondrocytic phenotype. These results suggest that Michael-type addition is an effective method in the preparation of in-situ forming, biodegradable GCH-based hydrogels serving as bio-scaffolds for chondrocyte culture. 相似文献
15.
Manda P Hargett JK Vaka SR Repka MA Murthy SN 《Drug development and industrial pharmacy》2011,37(11):1306-1310
The purpose of this study was to investigate the plausibility of delivery of cefotaxime to the brain via intranasal administration. In vitro permeation studies were carried out using Franz diffusion cells, and the effect of different concentrations of chitosan (0.1% w/v and 0.25% w/v) on drug permeation across the bovine olfactory mucosa was determined. Samples were collected from the receiver compartment at different time points and analyzed using HPLC. The amount of cefotaxime that permeated across the olfactory mucosa when 0.25% w/v of chitosan was used as a permeation enhancer was ~1.5- and ~2-fold higher at the end of the first hour and second hour, respectively, over control (29.56 ± 6.18 μg/cm(2)). There was no significant enhancement in drug permeation when 0.1% w/v chitosan was used as the permeation enhancer. Pharmacokinetic studies were carried out using Sprague-Dawley rats. Cefotaxime solution with 0.25% w/v chitosan (40 mg/kg) was administered intravenously (i.v.) to rats in groups 1 and 3 and intranasally to those in group 2 and 4. The time course of drug in the brain was investigated by performing microdialysis in rats of groups 1 and 2. Blood samples were withdrawn from rats in groups 3 and 4, and cefotaxime in plasma was analyzed using HPLC after extraction with a hydrochloric acid-chloroform:1-pentanol (3:1) and phosphate buffer solvent system. Pharmacokinetic parameters were calculated using the trapezoidal rule. The results imply that the drug levels attained in the brain following i.v. and intranasal administrations were comparable. These results suggest that intranasal administration of cefotaxime could be a potential method of delivering antibacterial agents because of it being noninvasive and patient compliant. 相似文献
16.
《Drug development and industrial pharmacy》2013,39(10):1160-1169
The aim of this study was to develop a pH-sensitive chitosan/polyvinyl pyrrolidone (PVP) based controlled drug release system for clarithromycin. The hydrogels were synthesized by cross-linking chitosan and PVP blend with glutaraldehyde to form a semi-interpenetrating polymer network (semi-IPN). These semi-IPNs were studied for their content uniformity, swelling index (SI), mucoadhesion, wettability, in vitro release and their release kinetics. The hydrogels showed more than 97% content of clarithromycin. These hydrogels showed high swelling and mucoadhesion under acidic conditions. The swelling may be due to the protonation of a primary amino group on chitosan. In acidic condition, chitosan would be ionized, and adhesion could have occurred between the positively charged chitosan and the negatively charged mucus. In the alkaline condition, less swelling and mucoadhesion was noticed. In vitro release study revealed that formulation containing chitosan (2% w/v) and PVP (4% w/v) in the ratio of 21:4 showed complete drug release after 12?h. Release profile showed that all the formulations followed non-Fickian diffusion mechanism. The cross-linking and compatibility of clarithromycin in the formulation was studied by Fourier transform infrared (FTIR) spectroscopic analysis, differential scanning calorimetry (DSC) and powder X-ray diffraction (p-XRD) study, which confirmed proper formation of semi-IPN and stability of clarithromycin in the formulations. The surface morphology of semi-IPN was studied before and after dissolution in simulated gastric fluid (SGF, pH 1.2) which revealed pores formation in membrane after dissolution. The results of study suggest that semi-IPNs of chitosan/PVP are potent candidates for delivery of clarithromycin in acidic environment. 相似文献
17.
以CMCTS-g-PAA和CMCTS-g-(PAANa-co-PVP)两类羧甲基壳聚糖改性阴离子型高吸水性树脂凝胶为研究对象,对其所吸收液体性能变化的响应性进行了研究。研究发现,阴离子型高吸水性树脂随乙醇/水混合溶剂中乙醇体积分数(φ)的增大发生体积相转变;随树脂结构中链段极性的增大,凝胶相变点相应的(φ)值降低;并随所吸收液体中低极性乙醇含量的增大,-COO-之间的相互排斥作用减弱,树脂的吸水速率降低。当研究溶液离子强度对树脂溶胀性能的影响时发现,1/S值较大时,离子强度与Q5/3成正比;但离子浓度较大时,Q5/3与1/S的线性关系消失。此外所吸收溶液的pH值对树脂的吸收率也有很大的影响。 相似文献
18.
Preparation,fabrication and biocompatibility of novel injectable temperature-sensitive chitosan/glycerophosphate/collagen hydrogels 总被引:1,自引:0,他引:1
Kedong Song Mo Qiao Tianqing Liu Bo Jiang Hugo M. Macedo Xuehu Ma Zhanfeng Cui 《Journal of materials science. Materials in medicine》2010,21(10):2835-2842
This paper introduces a novel type of injectable temperature-sensitive chitosan/glycerophosphate/collagen (C/GP/Co) hydrogel
that possesses great biocompatibility for the culture of adipose tissue-derived stem cells. The C/GP/Co hydrogel is prepared
by mixing 2.2% (v/v) chitosan with 50% (w/w) β-glycerophosphate at different proportions and afterwards adding 2 mg/ml of
collagen. The gelation time of the prepared solution at 37°C was found to be of around 12 min. The inner structure of the
hydrogel presented a porous spongy structure, as observed by scanning electron microscopy. Moreover, the osmolality of the
medium in contact with the hydrogel was in the range of 310–330 mmol kg−1. These analyses have shown that the C/GP/Co hydrogels are structurally feasible for cell culture, while their biocompatibility
was further examined. Human adipose tissue-derived stem cells (ADSCs) were seeded into the developed C/GP and C/GP/Co hydrogels
(The ratios of C/GP and C/GP/Co were 5:1 and 5:1:6, respectively), and the cellular growth was periodically observed under
an inverted microscope. The proliferation of ADSCs was detected using cck-8 kits, while cell apoptosis was determined by a
Live/Dead Viability/Cytotoxicity kit. After 7 days of culture, cells within the C/GP/Co hydrogels displayed a typical adherent
cell morphology and good proliferation with very high cellular viability. It was thus demonstrated that the novel C/GP/Co
hydrogel herein described possess excellent cellular compatibility, representing a new alternative as a scaffold for tissue
engineering, with the added advantage of being a gel at the body’s temperature that turns liquid at room temperature. 相似文献
19.
本研究首先在甲磺酸中用丙烯酰氯对壳聚糖(CS)进行接枝改性,通过一步法合成了水溶性丙烯酰基壳聚糖(CS-AC).之后,在光引发剂I2959和紫外光(UV)照下,以二硫苏糖醇(DTT)为交联剂制备了基于巯基-烯点击化学的CS-AC/DTT快速交联水凝胶.红外光谱(FTIR)和核磁共振氢谱(1 H-NMR)结果定性和定量地... 相似文献
20.
Huijuan Liao Hanwei Zhang Weiliam Chen 《Journal of materials science. Materials in medicine》2009,20(6):1263-1271
Marine derived gelatin is not known to associate with any communicable diseases to mammals and could be a reasonable substitute
for gelatin derived from either bovine or porcine sources. The low melting point of marine gelatin (8°C) also offers greater
formulation flexibility than mammalian derived gelatins. However, the sub-optimal physical properties of marine gelatin generally
limit the interest to further develop it for biomedical applications. This study aimed at investigating the feasibility of
using oxidized alginate (Oalg) as a high activity macromolecular crosslinker of marine gelatin to formulate in situ gelable
hydrogels with the goal of enhancing the latter’s physical properties. The performance of Oalg/marine gelatin hydrogel was
compared to Oalg/porcine gelatin hydrogel; in general, the physicomechanical properties of both hydrogels were comparable,
with the hydrogels containing porcine gelatin exhibiting moderately higher mechanical strengths with shorter gelation times,
smaller size pores, and higher swelling ratios. On the contrary, the biological performances of the two hydrogels were significantly
difference. Cells cultured in the marine gelatin derived hydrogel grew significantly faster, with greater than 60% more cells
by 7 days and they exhibited more spread-out conformations as compared those cultured in the porcine derived hydrogel. Production
of ECM by cells cultured in the Oalg/marine gelatin hydrogel was up to 2.4 times greater than that of in the Oalg/porcine
gelatin hydrogel. The biodegradation rate of the hydrogel formulated from marine gelatin was greater than its counterpart
prepared from porcine gelatin. These differences have important implications in the biomedical applications of the two hydrogels.
Huijuan Liao and Hanwei Zhang are the first authors. 相似文献