首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Vulvovaginal candidiasis (VVC) is a typical kind of vaginal mucosal infection. Herein, we developed a novel vaginal delivery system of amphotericin B (AmB) nanosuspension-loaded thermogel (AmB NPs/thermogel) utilising pharmaceutical technique of high-pressure homogenisation and Poloxamer P407/P188 hydrogel. The stabiliser and hydrogel materials of the formulation were tested to maintain proper sol–gel transition as well as the relative stability of the particle size of AmB nanosuspension in the thermogel. The particle size of AmB nanosuspensions in the hydrogel was ~247?nm. Transmission electron microscopy images confirmed the round-shape morphology of AmB nanoparticles in AmB NPs/thermogel, while that of irregular morphology of merely AmB nanosuspensions without stabiliser and hydrogel materials. AmB could be sustained release for ~12?h in vitro. In vivo drug content in the vaginal tissue was also evaluated with 87, 47, 33 and 6.7% drug remaining after 1, 3, 6 and 12?h, respectively. The in vivo anti-Candida test was conducted on candidiasis-infected mice model. In the same drug dose of 2.5?mg/kg, AmB NPs/thermogel showed better anti-Candida efficiency compared with commercial AmB effervescent tablet. This delivery system might show some insights for the vaginal formulation development of other hydrophobic antifungal drugs.  相似文献   

2.
Injectable In situ gel-forming chitosan/β-glycerol phosphate (CS/β-Gp) solution can be introduced into the body in a minimally invasive manner prior to solidifying within the target tissue. This hydrogel is a good candidate for achieving a prolonged drug delivery system for insulin considering its high molecular weight. In addition to the physicochemical characterization of this hydrogel, in vitro and in vivo applications were studied as a sustained insulin delivery system. In the in vitro release studies, 19–63% of total insulin was released from the CS/β-Gp hydrogel within 150?h at different β-Gp and insulin concentrations. The best formulation was selected for in vivo experimentation to control the plasma glucose of diabetic mice models. The hypoglycemic effect of this formulation following subcutaneous injection in diabetic mice lasted 5?d, significantly longer than that of free insulin solution which lasted several hours.  相似文献   

3.
N-[(2-Hydroxy-3-trimethylammonium)propyl] chitosan chloride (HTCC) was chemically modified using glycidyltrimethylammonium chloride (GTMAC). A new composite hydrogel was prepared using the mixture of HTCC and α-β-glycerophosphate (α-β-GP). The gelation of HTCC/GP mainly depended on the concentration and proportion of HTCC and GP. Thermogravimetric analysis exhibited high stability of HTCC/GP hydrogels. Surface morphology assay demonstrated that HTCC/GP hydrogels were well constructed with three-dimensional (3D) porous structures in the range of 5 of 40 μm. The insulin was entrapped during the formation of hydrogel. In vitro, the insulin release was controlled by modifying the composition, drug loading, and pH condition. The hydrogel dissolved and released drug quickly under acidic condition, whereas it absorbed water and released drug slowly under neutral or basic conditions. The hydrogels were biocompatible, and the cells could adhere to and then migrated to the hydrogels. Furthermore, these cells were viable and retained 3D morphology inside the hydrogels. Interestingly, HTCC/GP hydrogel showed both thermo- and pH-sensitive properties. There are potential applications in tissue engineering, cell encapsulation, and intelligent drug delivery systems.  相似文献   

4.
目的研究壳聚糖/羧甲基壳聚糖/甘油磷酸钠(CS/CMCS/GPS)体系水凝胶的温敏性,载药凝胶以及共混β-环糊精(β-CD)包合物对药物的缓释性能。方法试管倒置法研究不同配比,不同pH值对CS/CMCS/GPS体系温敏凝胶化性能的影响;饱和水溶液法制备吲哚美辛/β-CD包合物,红外光谱表征包合物;紫外分光光度法测定包合物载药量和药物的累积释放度。结果 2%CS-2%CMCS-56%GPS体积比从10∶1∶2变为10∶10∶2(体系pH6.8),37℃下凝胶化时间由370s升至490s,后又降至90s;三者体积比从10∶3∶1变为10∶3∶6(体系pH6.8),37℃下凝胶化时间从407s降至66s。pH值在6.8~7.2范围适合于体系凝胶化。调节体积比及合适的pH值,在37℃下可实现CS/CMCS/GPS体系快速凝胶化。以吲哚美辛和吲哚美辛/β-CD包合物为模型药物,载有吲哚美辛温敏凝胶12h的累积释放度为65.2%,载有吲哚美辛/β-CD包合物温敏凝胶累积释放度为52.8%,而吲哚美辛原药12h的累积释放度为87.6%,吲哚美辛/β-CD包合物的累积释放度为82.1%。结论一定体积配比CS/CMCS/GPS体系在37℃具有快速凝胶特性,β-CD包合物与温敏性凝胶共混,对药物具有更加明显的缓释作用。  相似文献   

5.
Rosuvastatin (RSV) has been shown to have significant impact on the simulation of bone regeneration after local injection. The current study aimed to develop a localized controlled delivery system from RSV by incorporating RSV-loaded chitosan/chondroitin sulfate (CTS/CS) nanoparticles into thermosensitive Pluronic F127/hyaluronic acid (PF127/HA) hydrogel. RSV-loaded CTS/CS nanoparticles were prepared by ionic gelation, and the impact of various formulation variables was assessed using the Box–Behnken design. Consequently, optimized RSV-loaded nanoparticles were incorporated into the PF127/HA hydrogel. Rheological properties, degradation rates of hydrogels, and the release rate of RSV from hydrogel were examined. Mean particle size, zeta potential, entrapment efficiency, and mean release time of the optimized RSV-loaded nanoparticles were confirmed as 283.2?±?16?nm, –31.2?±?6.8?mV, 63.1?±?4.2%, and 6.14?±?0.3?h, respectively. The hydrogel containing 3% w/v CTS/CS nanoparticles existed as a solution with low viscosity at room temperature converted to a semisolid upon increasing the temperature to 35?°C. Hydrogel engrafted with CTS/CS showed controlled release of RSV during 48?h with superior in vitro gel stability. As revealed by cytotoxicity and mineralization assays, incorporation of RSV-loaded particles into PF127/HA hydrogel led to improvement in osteoblast viability and proliferation.  相似文献   

6.
Abstract

Topotecan hydrochloride (TPT) has potential for the treatment of ovarian cancer, but the activity of TPT tends to decrease due to the ring-opening at physiological pH. In this study, we proposed to incorporate TPT liposomes into injectable thermosensitive in situ hydrogel, consisting of chitosan (CS) and β-glycerophosphate (β-GP), for sustained release and preservation of active lactone form of TPT. The rheology studies were carried out to investigate the sol–gel temperature, flow behavior and viscosity of these CS/β-GP systems. The optimized formulation exhibited sol–gel transition at 40.2?±?0.4?°C, with pseudoplastic flow behavior. The drug release rate of TPT liposomes loaded CS/β-GP hydrogel in phosphate buffer saline (pH?=?7.4) was found to be slowed down, and the lactone fraction of TPT in the hydrogel matrix was maintaining 40% after 50?h. In addition, the antitumor efficacy in Kunming mice bearing Hepatoma-22 tumor, after intratumoral injection of TPT liposomes loaded CS/β-GP hydrogel, was higher than that of TPT in saline and TPT in CS/β-GP hydrogel. Those results demonstrated that TPT liposomes loaded CS/β-GP hydrogel could become a potential formulation for improving the antitumor efficacy of TPT and suggested an important technology platform for intratumoral administration of derivative of camptothecin-family drugs.  相似文献   

7.
8.
Systemic rheumatoid arthritis (RA) regimens fail to attain effective drug level at the affected joints and are associated with serious side effects. Herein, an attempt made to improve therapeutic outcomes of both leflunomide (LEF) which is a disease modifying antirheumatic and dexamethasone (Dex) through local delivery of combination therapy by intra-articular route. LEF and Dex were encapsulated in nanostructured lipid carriers (NLCs) and PLGA nanoparticles (NPs), respectively. Both nanocarriers were loaded into chitosan/β glycerophosphate (CS/βGP) thermo-sensitive hydrogels and injected intra-articularly in adjuvant induced RA rat model. Particle size of LEF NLCs and selected Dex NPs formulations were 200 and 119 nm, respectively. Dex NPs and LEF NLCs showed a sustained release profile for up to 58 and 17 days, respectively. After 14 days of treatment remarkable joint healing was observed for groups treated with Dex NPs in combination with either free LEF or LEF NLCs in CS/βGP hydrogel. Joint diameter measurements, TNF α levels and histopathological examination of dissected joints showed comparable values to the negative control group. This might be attributed to the synergistic effect of drug combination besides the ability of nanocarriers loaded hydrogel to prolong joint residence time and enhance joint healing potential.  相似文献   

9.
《Pharmaceutical biology》2013,51(5):642-652
Abstract

Context: Nanotechnology can be applied to deliver and protect antioxidants in order to control the oxidative stress phenomena in several chronic pathologies. Chitosan (CS) nanoparticles are biodegradable carriers that may protect antioxidants with potent biological activity such as rosmarinic acid (RA) in Salvia officinalis (sage) and Satureja montana (savory) extracts for safe and innovative therapies.

Objective: Development and characterization of CS nanoparticles as a stable and protective vehicle to deliver RA for medical applications using natural extracts as sage and savory.

Materials and methods: Antioxidant-CS based nanoparticles were prepared by ionic gelation with sodium tripolyphosphate (TPP), at pH 5.8 with a mass ratio of 7:1 (CS:TPP), with a theoretical antioxidant-CS loading of 40–50%. The nanoparticles were then characterized by different methods such as photon correlation spectroscopy, laser Doppler anemometry, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR), high-performance liquid chromatographic (HPLC), association efficiency, and antioxidant activity.

Results and discussion: Individual and small sizing nanoparticles, around 300?nm, were obtained. SEM confirmed smooth and spherical nanoparticles after freeze-drying. No chemical interactions were found between antioxidants and CS, after encapsulation, by DSC and FTIR. The association efficiency was 51.2% for RA (with 40% loading) and 96.1 and 98.2% for sage and savory nanoparticles, respectively (both with 50% loading). Antioxidant activity values were higher than 0.0348?eq [Asc. Ac.] g/L/g extract and 0.4251?µmol/eq Trolox/g extract.

Conclusion: The extracts under study are promising vehicles for RA drug delivery in CS nanocarriers.  相似文献   

10.
Abstract

In this study, a thermoresponsive gel for minocycline (MCL) with chitosan/β-glycerophosphate (C/β-GP) was formulated and its characterization, in vitro release, stability, toxicity and pharmacodynamics were investigated. The formulation containing MCL was prepared by pouring the chitosan solution directly onto the sterilized drug powder and stirring before mixing with the β-glycerophosphate (β-GP) solution. The final preparations contained 0.5% (w/v) chitosan, 1.8% (w/v) β-GP and 2% (w/v) MCL. The drug content of prepared gels was in the range of 92–99%, and the pH value of the optimized formulation was found to be 5.6–6.2. The gelation temperature of the prepared C/β-GP thermogelling solutions was 37?°C. Color, consistency, pH, viscosity and drug content of the in situ gels were found to be consistent, and no signs of separation and deterioration were observed over a period of 90 d. In vivo studies showed that rats' liver and kidney tissue sections were normal, with no structural damage. The constituents of the in situ gels formulation had a well-sustained release efficacy on the animal model of periodontitis.  相似文献   

11.
Xue Wang  Jin Wang  Wenbin Wu 《Drug delivery》2016,23(9):3544-3551
Local tumor recurrence after cervical cancer surgery remains a clinical problem. Vaginal delivery of thermosensitive hydrogel may be suited to reduce tumor relapse rate with more efficacy and safety. A pilot study was carried out to evaluate the efficacy of carboplatin-loaded poloxamer hydrogel to prevent local recurrence of cervical cancer after surgery. In vivo vaginal retention evaluation of 27% poloxamer hydrogel in mice was proven to be a suitable vaginal drug delivery formulation due to its low gelation temperature. A mimic orthotopic cervical/vaginal cancer recurrence model after surgery was established by injecting murine cervical cancer cell line U14 into the vaginal submucosa to simulate the residual tumor cells infiltrated in the surgical site, followed by drug administration 24?h later to interfere with the formation/recurrence of the tumor. By infusing fluorescein sodium-loaded hydrogel into the vagina of mice, a maximized accumulation of fluorescein sodium (Flu) in the vagina was achieved and few signals were observed in other organs. When used in the prevention of the cervical cancer formation/recurrence in mice, the carboplatin-loaded poloxamer hydrogel exhibited great efficacy and systemic safety. In conclusion, thermosensitive hydrogel presents a simple, practical approach for the local drug delivery via vagina against cervical cancer recurrence.  相似文献   

12.
Hydrophilic nanoparticles have received much attention for delivery of therapeutic peptides, proteins, and antigens. Chitosan (CS) is a biodegradable and nontoxic polysaccharide, as a carrier for drug delivery. The study purpose was to evaluate the influence of a number of factors on the encapsulation of Naja naja oxiana (Indian or speckled cobra) venom and loading capacity, as well as to investigate the physicochemical structure of nanoparticles. CS nanoparticles were produced based on the ionic gelation process of tripolyphosphate (TPP) and CS. All the preparations were estimated with diameter 120–150 nm and spherical shape using transmission electron microscopy. Fourier transform–infrared spectroscopy confirmed that tripolyphosphoric groups of TPP linked with ammonium groups of CS in the nanoparticles. Our results showed that CS can react with TPP to form stable cationic nanoparticles. Therefore, when chitosan concentration was increased to 1.5 mg/mL the aggregates with large diameter were formed. Optimum loading capacity and encapsulation efficiency of venom at a concentration of 500 μg/mL were achieved for low-molecular-weight (low-MW) CS at a concentration of 2 mg/mL and high-MW CS at a concentration of 3 mg/mL.From the Clinical EditorIn this study a hydrophilic nanoparticle chitosan was investigated as a protein delivery system, and optimum conditions were established for future use of this technology.  相似文献   

13.
The present study aimed to prepare a chemically and physically stable formulation of doxycycline (Doxy) in an in situ thermally sensitive hydrogel for ophthalmic delivery. An inclusion complex of Doxy and hydroxypropyl-β-cyclodextrin (HP-β-CD) was first developed to increase the stability of Doxy in aqueous solution. The physical characteristics (phase solubility profiles, thermal analysis, X-ray powder diffractograms and infrared spectra) of the Doxy-HP-β-CD inclusion complex indicated the formation of a stable 1:1 complex. Poloxamers P407 (16–22%) and P188 (0–5%) were mixed to obtain a hydrogel with an appropriate gelation temperature for opthalmic use. Formulation of the inclusion complex in the poloxamer hydrogel exhibited a suitable gelation temperature (33.3 °C) after dilution with simulated tear fluid (Gel:STF=40:7, v/v). The release of Doxy from the poloxamer hydrogel followed a zero order equation suggesting it occurs through corrosion of the poloxamer hydrogel. Stability studies demonstrated that the inclusion of Doxy by HP-β-CD markedly improved its stability in aqueous solution both at 8 and 40 °C. This formulation of a doxycycline-HP-β-CD inclusion complex in an in situ thermally sensitive poloxamer hydrogel represents a potentially effective ophthalmic Doxy delivery system.  相似文献   

14.
The aim of this work was the assessment of the “in vivo” immune response of a poly(lactide-co-glycolide)-based nanoparticulate adjuvant for a sub-unit vaccine, namely, a purified recombinant collagen-binding bacterial adhesion fragment (CNA19), against Staphylococcus aureus-mediated infections. “In vivo” immunogenicity studies were performed on mice: immunisation protocols encompassed subcutaneous and intranasal administration of CNA19 formulated as nanoparticles (NPs) and furthermore, CNA19-loaded NPs formulated in a set-up thermosetting chitosan-β-glycerolphosphate (chitosan-β-GP) solution for intranasal route in order to extend antigen exposure to nasal mucosa. CNA19 loaded NPs (mean size of about 195?nm, 9.04?±?0.37μg/mg as CNA19 loading capacity) confirmed as suitable vaccine for subcutaneous administration with a more pronounced adjuvant effect (about 3-fold higher) with respect to aluminium, recognised as “reference” adjuvant. CNA19 loaded NPs formulated in an optimised thermogelling chitosan-β-GP solution showed promising results for eliciting an effective humoral response and a good chance as intranasal boosting dose.  相似文献   

15.
Ganciclovir (GCV) is one of the most widely used antiviral drugs for the treatment of cytomegalovirus (CMV) retinitis. In this context, the aim of this study was to design in situ thermosensitive hydrogels for GCV ocular delivery by intravitreal injection to achieve sustained drug release behavior and improved ocular bioavailability in the treatment of CMV retinitis. A thermosensitive poly-(β-butyrolactone-co-lactic acid)-polyethylene glycol-poly (β-butyrolactone-co-lactic acid) (PBLA-PEG-PBLA) triblock copolymer was synthesized by ring-opening polymerization and characterization. The GCV-loaded PBLA-PEG-PBLA in situ hydrogels (15%, w/w) were then prepared with drug concentration at 2?mg·mL?1 and the gelation temperatures, rheological properties, in vitro degradation and syringeability of in situ hydrogels for intravitreal injection were also investigated. Membraneless dissolution model was used to explore drug release behavior of PBLA-PEG-PBLA in situ hydrogel. The results indicated that more than 45 and 85% of GCV can be released within 24 and 96?h, respectively, which was verified by a non-Fickian diffusion mechanism. In vivo ocular pharmacokinetics study showed that area under drug-time curve (AUC) and half-life of PBLA-PEG-PBLA in situ hydrogel was higher (AUC was 61.80?μg·mL?1·h (p?t1/2 was 10.29?h in aqueous humor; AUC was 1008.66?μg·mL?1·h (p?t1/2 was 13.26?h (p?in situ hydrogel is a promising carrier of GCV for intravitreal injection.  相似文献   

16.
Pingyangmycin (PYM) has been applied clinically for many years to treat vascular malformations (VM) in China. The major limitation of PYM injections is quick diffusion from the injection site, which increases side effects, especially the possibility of pulmonary injury. In this paper, chitosan/glycerophosphate disodium (CS/GP) thermogels containing liposomes for sustained and localized PYM delivery were prepared and optimized by a three-level three-factorial Box–Behnken experimental design to evaluate the effects of different variables (the PYM concentration, CS amount and GP content), on the selected responses (cumulative percentage PYM released in 1?day, 9 days and the rate constant k). The results revealed that the optimized PYM liposomal thermogels had a controlled PYM release for 14 days in vitro, which confirmed the validity of optimization. In vitro morphological observation, cell cycle and apoptosis analysis showed an effective anti-proliferation action of PYM liposomal thermogels on human vascular endothelial cells (EA.hy926). In vivo pharmacokinetics research in rabbits displayed that compared with PYM liposomes and PYM thermogels, PYM liposomal thermogels had a better controlled delivery of PYM. Histological examination of rabbit ear veins showed that after local application with PYM lipsomal thermogels for 21 days, obvious vein thrombosis and inflammatory reaction could be observed. The above results indicated that PYM-loaded lipsomal CS/GP thermogels might have a good prospect for the treatment of VM.  相似文献   

17.
Objectives: Thermosensitive chitosan/glycerophosphate (C/GP) solutions exhibiting sol–gel transition around body temperature were prepared to develop a class of injectable hydrogel platforms for the imaging and loco-regional treatment of hepatocellular carcinoma (HCC). Indocyanine green (ICG) was loaded in the thermosensitive solutions in order to assess their potential for the detection of tumor nodules by fluorescence.

Methods: The gel formation of these formulations as well as their gelling time, injectability, compactness and resistance of gel structure, gelling temperature, storage conditions, biodegradability, and in vitro dye release behavior were investigated. Ex vivo studies were carried out for preliminary evaluation using an isolated bovine liver.

Results: Gel strengths and gelation rates increased with the cross-link density between C and GP. These behaviors are more evident for C/GP solutions, which displayed a gel-like precipitation at 4°C. Furthermore, formulations with the lowest cross-link density between C and GP exhibited the best injectability due to a lower resistance to flow. The loading of the dye did not influence the gelation rate. ICG was not released from the hydrogels because of a strong electrostatic interaction between C and ICG. Ex vivo preliminary studies revealed that these injectable formulations remain in correspondence of the injected site.

Conclusions: The developed ICG-loaded hydrogels have the potential for intraoperative fluorescence imaging and local therapy of HCC as embolic agents. They form in situ compact gels and have a good potential for filling vessels and/or body cavities.  相似文献   

18.
A novel injectable thermosensitive in situ gelling hydrogel has been developed. The system, which falls under the BST-Gel platform technology developed at Biosyntech Inc. (Laval, QC, Canada), consists of a chitosan solution (C) neutralized with beta-glycerophosphate (GP) that is liquid at room temperature but gels when heated to body temperature. We propose to use this thermosensitive hydrogel for the sustained release of paclitaxel at tumor resection sites in order to prevent local tumor recurrence. The in vitro release profiles demonstrated controlled delivery over 1 month. The initial drug loading substantially affected the release. Local delivery of paclitaxel from the formulation injected intratumorally was investigated using EMT-6 tumors implanted subcutaneously on Balb/c mice. These experiments showed that one intratumoral injection of the thermosensitive hydrogel containing paclitaxel was as efficacious as four intravenous injections of Taxol in inhibiting the growth of EMT-6 cancer cells in mice, but in a less toxic manner. Further histological analysis revealed that while the proportion of necrotic areas was similar for the C/GP/paclitaxel and the Taxol-treated tumors, a disparity between tumor-associated inflammatory cell populations may suggest differing anti-tumor mechanisms.  相似文献   

19.
The quaternized chitosan was synthesized by the reaction of chitosan and glycidyltrimethylammonium chloride (GTMAC) and named as N-[(2-hydroxy-3-trimethylammonium) propyl] chitosan chloride (HTCC). A novel hydrogel system composed of HTCC/glycerophosphate (HTCC/GP) with thermo- and pH-sensitivity was synthesized and used as an intelligent drug carrier. The formulation was solution below or at room temperature, which allowed it injectable and to incorporate living cells, proteins, enzymes or other therapeutic drugs easily. Once the surrounding temperature was up to 37 degrees C, the system was transformed to a non-flowing hydrogel, and the formed hydrogel can release the trapped drug as a function of pH values. The swelling behavior of the system and the release profiles of doxorubicin hydrochloride (DX) as a model drug at different pH values were investigated. At acidic condition the hydrogel dissolved and released drug quickly, while it absorbed water and released drug slowly at neutral or basic conditions. Hydrogel composed of chitosan hydrochloride and glycerophosphate (CS/GP) was also prepared to compare with HTCC/GP hydrogel. The HTCC/GP hydrogel in this study was transparent which made it suitable for some specific uses such as ocular drug formulation.  相似文献   

20.
目的:制备具有温敏性并具有一定强度的凝胶。方法:采用壳聚糖(CS)、聚乙烯醇(PVA)和甘油磷酸钠(GP)为基质,以CS的浓度(A)、CS与PVA质量比(B)及pH值(C)为考察因素,以初始凝胶化温度、凝胶强度和脱水情况为指标,采用正交设计优化凝胶处方,并进行验证试验。结果:优化处方为A20mg·mL-1、B1∶1、C7.2。所制凝胶水溶液在4℃和室温下为可流动的液体,于37℃、10min内可发生凝胶化,随温度升高凝胶化所需时间明显缩短,凝胶强度为1.4kPa,凝胶在体外降解过程中28d内pH值几乎不变。结论:CS/PVA/GP凝胶的制备工艺简单可行,并具有温敏性和一定强度。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号