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1.
The objective of this study was to develop the microspheres from gelatin (G) and silk fibroin (SF) aimed to be applied for the controlled release of curcumin and piperine. The glutaraldehyde-crosslinked G/SF microspheres at various weight blending ratios (100/0, 70/30, 50/50, and 30/70) were successfully fabricated by water in oil emulsion technique. The microspheres prepared from all compositions were in a round shape with homogeneous size distribution both in the dried (194–217 μm) and swollen states (297–367 μm). When subjected in collagenase solution at physiological condition, the G microspheres gradually degraded within 14 days while the blended G/SF microspheres, particularly at 50/50 and 30/70, were not degraded. For the release application, the microspheres were loaded with curcumin and/or piperine. It was found that the microspheres composed of SF tended to entrap curcumin and piperine with the high entrapment and loading efficiencies, possibly due to their hydrophobic interactions. The G/SF microspheres, particularly at the ratios of 50/50 and 30/70, released curcumin and piperine in a sustained manner both for the single and dual release systems. The controlled dual release of curcumin and piperine from the G/SF microspheres would prolong their half-life, provide the optimal concentrations for therapeutic effects at a target site, and improve the bioavailability of curcumin. These novel injectable microspheres dually releasing curcumin and piperine would be introduced for the treatment of diseases without the need of operation.  相似文献   

2.
The purpose of this study was to prepare a poly(lactide-co-glycolide) (PLGA) encapsulated hydroxyapatite microspheres (HAP-MSs) as injectable depot for sustained delivery of Doxycycline (Doxy). Doxy loaded HAP-MSs (Doxy-HAP-MSs) were encapsulated with PLGA by solid-in-oil-in-water (S/O/W) emulsion-solvent evaporation technique, the effects of the PLGA used (various intrinsic viscosity and LA/GA ratio) and ratio of PLGA/HAP-MSs on the formation of Doxy-HAP-MSs and in vitro release of Doxy were studied. The results showed that sustained drug release without obvious burst was obtained by using PLGA encapsulated HAP-MSs as the carrier, also the drug release rate could be tailored by changing the ratio of PLGA/HAP-MSs, or PLGA of various intrinsic viscosities or LA/GA ratio. Lower ratio of PLGA/HAP-MSs corresponded faster Doxy release, e.g. for the microspheres of PLGA/HAP-MSs ratio of 8 and 0.25, the in vitro Doxy release percents at the end of 7days were about 23% and 76%, respectively. Higher hydrophilicity (higher ratio of GA to LA) and lower molecular weight of PLGA corresponded to higher Doxy release rates. For in vivo release study, PLGA encapsulated HAP-MSs were subcutaneously injected to the back of mice, and the results showed good correlation between the in vivo and in vitro drug release. Meanwhile, the plasma Doxy levels after subcutaneous administration of PLGA encapsulated Doxy-HAP-MSs were relatively lower and steady compared to that of the un-encapsulated microspheres. In conclusion, PLGA encapsulated HAP-MSs may be a potential vehicle for the sustained delivery of Doxy.  相似文献   

3.
Despite advances in controlled drug delivery, reliable methods for activatable, high‐resolution control of drug release are needed. The hypothesis that the photothermal effect mediated by a near‐infrared (NIR) laser and hollow gold nanospheres (HAuNSs) could modulate the release of anticancer agents is tested with biodegradable and biocompatible microspheres (1–15 µm) containing the antitumor drug paclitaxel (PTX) and HAuNSs (≈35 nm in diameter), which display surface plasmon absorbance in the NIR region. HAuNS‐containing microspheres exhibit a NIR‐induced thermal effect similar to that of plain HAuNSs. Rapid, repetitive PTX release from the PTX/HAuNS‐containing microspheres is observed upon irradiation with NIR light (808 nm), whereas PTX release is insignificant when the NIR light is switched off. The release of PTX from the microspheres is readily controlled by the output power of the NIR laser, duration of irradiation, treatment frequency, and concentration of HAuNSs embedded inside the microspheres. In vitro, cancer cells incubated with PTX/HAuNS‐loaded microspheres and irradiated with NIR light display significantly greater cytotoxic effects than cells incubated with the microspheres alone or cells irradiated with NIR light alone, owing to NIR‐light‐triggered drug release. Treatment of human U87 gliomas and MDA‐MB‐231 mammary tumor xenografts in nude mice with intratumoral injections of PTX/HAuNS‐loaded microspheres followed by NIR irradiation results in significant tumor‐growth delay compared to tumors treated with HAuNS‐loaded microspheres (no PTX) and NIR irradiation or with PTX/HAuNS‐loaded microspheres alone. The data support the feasibility of a therapeutic approach in which NIR light is used for simultaneous modulation of drug release and induction of photothermal cell killing.  相似文献   

4.
李倩  吴庆生 《材料导报》2015,29(14):40-44, 51
采用乳化交联法制备了载碘胺铂壳聚糖微球,用扫描电镜和红外光谱对其结构及形貌进行了表征。载碘胺铂壳聚糖微球的平均载药量为(46.48±4.42)%,平均包封率为(91.39±2.45)%,缓释测试符合一级释药方程。MTT实验证明载碘胺铂壳聚糖微球能抑制肝癌细胞生长,且比单纯使用碘胺铂高。  相似文献   

5.
Vector plays an important role in hepatic targeted drug delivery system. In this study, a novel material as a liver targeting vector, dual-ligand modified chitosan (GCGA) composed of chitosan (CTS), glycyrrhetinic acid (GA) and lactobionic acid (LA), was designed and synthesized by an orthogonal experiment with two-step synthesis under mild conditions. The synthesized final product was characterized and confirmed by FTIR and 1H-NMR spectroscopy, and DS of GA and LA in CTS were measured to be 13.77 and 16.74 mol% using 1H-NMR, respectively. The cytotoxicity of CTS and GCGA was concentration dependent which was inverse proportion to the cell viability by MTT assay using L929 cell line, and inhibitory concentration 50% (IC50) was 0.2 mg/ml for GCGA. The in vitro targeting efficiency and the in vitro cellular uptake were investigated. Compared with CTS NPs and GA-CTS NPs, GCGA NPs showed good cell specificity to BEL-7402 cells via the dual-ligand-receptor-mediated recognition, leading to a higher affinity to BEL-7402 cells. The results suggested that GCGA described here has the potential to be used as an effective vector for hepatic targeted drug therapy.  相似文献   

6.
通过静电纺丝法,制备了 MnO2-聚多巴胺(PDA)/聚乙烯醇(PVA)和MnO2-PDA-5-氟尿嘧啶(5-Fu)/PVA复合微球.具体地,在PVA溶液中依次加入多巴胺(DA)与KMnO4,在所得溶液中,DA与KMnO4发生氧化还原反应,原位聚合生成PDA,而KMnO4转变为MnO2,通过静电纺丝法制备了 MnO2-...  相似文献   

7.
Bioglass®-based scaffolds for bone tissue engineering have been developed, which can also serve as carriers for drug delivery. For this, P(3HB) microspheres (PMSs) loaded with tetracycline were fabricated and immobilised on the scaffold surfaces by a modified slurry dipping technique. The sustained drug delivery ability in simulated body fluid was confirmed by using UV–Vis absorption spectroscopy measurements. The MTT assay using mouse fibroblast cells provided evidence that the tetracycline loaded microspheres produced in this study show limited cytotoxicity. The scaffolds developed in this work provide mechanical support, adequate 3D surface roughness, bioactivity and controlled drug delivery function, and are thus interesting candidates for bone tissue engineering applications.  相似文献   

8.
陈铖  丁晶鑫  王会  王德平 《无机材料学报》2022,37(11):1245-1258
骨肉瘤是一种常见的恶性骨肿瘤, 常通过手术切除进行治疗。但术后造成的骨缺损难以自愈, 残余肿瘤细胞还会增加复发可能性。本研究开发了一种用于修复骨缺损和协同治疗骨肉瘤的掺钕介孔硼硅酸盐生物活性玻璃陶瓷骨水泥。首先通过溶胶-凝胶法结合固态反应制备了可作为光热剂和药物载体的掺钕介孔硼硅酸盐生物活性玻璃陶瓷微球(MBGC-xNd), 然后将微球与海藻酸钠(SA)溶液混合制备了可同时进行光热治疗和化学治疗的可注射骨水泥(MBGC-xNd/SA)。结果表明掺Nd3+赋予微球可控的光热性能, 负载阿霉素(DOX)的微球显示出持续的药物释放行为。此外, 载药骨水泥的药物释放量随着温度的升高而显著增加, 说明光热疗法产生的热量可促进DOX释放。体外细胞实验结果表明, MBGC-xNd/SA具有良好的促成骨活性, 并且光热-化学联合疗法对MG-63骨肉瘤细胞起到了更显著的杀伤作用, 表现出协同效应。因此,MBGC-xNd/SA作为一种新颖的多功能骨修复材料, 在骨肉瘤的术后治疗方面具有良好的应用前景。  相似文献   

9.
Poly(1,3-bis-(p-carboxyphenoxy propane)-co-(sebacic anhydride) (P(CPP-SA)) have the anhydride bonds in copolymer backbone, which are available for degradation on the base of passive hydrolysis. This chemical structure made it degraded within a short time in linear degradation rate. For this property, polyanhydrides are one of the most suitable biodegradable polymers employed as drug carriers. This paper aimed at researching the erosion and degradation of P(CPP-SA) microspheres with CPP/SA monomer ratios of 20:80, 35:65 and 50:50. In vitro protein release from the microspheres was also investigated in this paper. Human serum albumin (HSA) was used as the model protein. In this research, the microspheres degradation and drug release rate from microspheres can be adjusted by altering the CPP/SA ratios of P(CPP-SA). The features of surface erosion were observed in SEM. The structural integrity of HSA extracted from microspheres was detected by gel permeation chromatography, compared with native HSA. The results showed HSA remained its molecule weight after encapsulated.  相似文献   

10.
The aim of the present study was to extend the use of flurbiprofen in clinical settings by avoiding its harmful gastric effects. For this purpose, we designed the controlled release solid lipid flurbiprofen microspheres (SLFM) by emulsion congealing technique. Drug was entrapped into gastro resistant biodegradable beeswax microspheres which were prepared at different drug/beeswax ratios 1:1, 1:2 and 1:3 using gelatin and tween 20 as emulsifying agents. The effect of emulsifiers and the effect drug/beeswax ratios were studied on hydration rate, encapsulating efficiency, micromeritic properties, scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (X-RD) analysis and in vitro drug release at pH 1.2 for 2 h and at pH 6.8 for 10 h. SEM revealed that microspheres made with tween 20 were smooth while microspheres made with gelatin showed porous morphology, however, they were all spherical in nature. The practical yield (recovery) showed a dependence on drug-beeswax ratio and it was variable from 53 to 84%. High loading encapsulating efficiency of flurbiprofen from 8 to 94% was achieved. FTIR and DSC analysis confirmed the absence of any drug polymer interaction indicating drug stability during microencapsulation. X-RD of pure flurbiprofen shows sharp peaks, which decreases on encapsulation, indicating decrease in the crystallinity of drug in microspheres. The micromeritic studies confirmed the presence of excellent and good flow properties of microspheres. Entrapment efficiency, morphology, practical yield, hydration rate, flow properties demonstrated their dependence on the HLB value of emulsifiers and emulsifiers with higher HLB were found more appropriate for effective microencapsulation of flurbiprofen. The release kinetics followed zero order mechanism of drug release at pH 6.8. Release pattern depends on the morphology of flurbiprofen microspheres and amount of beeswax used in the microspheres preparation. The microspheres prepared with high HLB values i.e., tween 20 showed effective control of drug release from microspheres. The absence of drug release at pH 1.2 proved the suitability of beeswax for its use as a gastro resistant material.  相似文献   

11.
Abstract

Poly (D, L-lactic acid) (PLA) microspheres containing testosterone enanthate (ET) were prepared by using an oil-in-water (O/W) emulsion technique. The size distribution of the microspheres obtained could be explained by a log-normal distribution, and as a result, it was found that ET fully incorporates into microspheres even when the drug is loaded at up to 50%. On the other hand, the dissolution behavior of ET from microspheres was strongly dependent on particle size, suggesting that dissolution of the drug from microspheres can be easily controlled by controlling the preparative conditions.  相似文献   

12.
DC Bead® is a drug delivery embolisation system that can be loaded with doxorubicin or irinotecan for the treatment of a variety of liver cancers. In this study we demonstrate that the topoisomerase I inhibitor topotecan hydrochloride can be successfully loaded into the DC Bead sulfonate-modified polyvinyl alcohol hydrogel matrix, resulting in a sustained-release drug eluting bead (DEBTOP) useful for therapeutic purposes. The in vitro drug loading capacity, elution characteristics and the effects on mechanical properties of the beads are described with reference to our previous work with irinotecan hydrochloride (DEBIRI). Results showed that drug loading was faster when the solution was agitated compared to static loading and a maximum loading of ca. 40–45 mg topotecan in 1 ml hydrated beads was achievable. Loading the drug into the beads altered the size, compressibility moduli and colour of the bead. Elution was shown to be reliant on the presence of ions to perform the necessary exchange with the electrostatically bound topotecan molecules. Topotecan was shown by MTS assay to have an IC50 for human pancreatic adenocarcinoma cells (PSN-1) of 0.22 and 0.27 μM compared to 28.1 and 19.2 μM for irinotecan at 48 and 72 h, respectively. The cytotoxic efficacy of DEBTOP on PSN-1 was compared to DEBIRI. DEPTOP loaded at 6 &; 30 mg ml?1, like its free drug form, was shown to be more potent than DEBIRI of comparable doses at 24, 48 &; 72 h using a slightly modified MTS assay. Using a PSN-1 mouse xenograft model, DEBIRI doses of 3.3–6.6 mg were shown to be well-tolerated (even with repeat administration) and effective in reducing the tumour size. DEBTOP however, was lethal after 6 days at doses of 0.83–1.2 mg but demonstrated reasonable efficacy and tolerability (again with repeat injection possible) at 0.2–0.4 mg doses. Care must therefore be taken when selecting the dose of topotecan to be loaded into DC Bead given its greater potency and potential toxicity.  相似文献   

13.
Abstract

Enteric-coated epichlorohydrin crosslinked dextran microspheres containing 5-Fluorouracil (5-FU) for colon drug delivery was prepared by emulsification-crosslinking method. The formulation variables studied includes different molecular weights of dextran, volume of crosslinking agent, stirring speed, time and temperature. Dextran microspheres showed mean entrapment efficiencies ranging between 77 and 87% and mean particle size ranging between 10 and 25?µm. About 90% of drug was released from uncoated dextran microspheres within 8?h, suggesting the fast release and indicated the drug loaded in uncoated microspheres, released before they reached colon. Enteric coating (Eudragit-S-100 and Eudragit-L-100) of dextran microspheres was performed by oil-in-oil solvent evaporation method. The release study of 5-FU from coated dextran microspheres was complete retardation in simulated gastric fluid (pH 1.2) and once the coating layer of enteric polymer was dissolved at higher pH (7.4 and 6.8), a controlled release of the drug from the microspheres was observed. Further, the release of drug was found to be higher in the presence of dextranase and rat caecal contents, indicating the susceptibility of dextran microspheres to colonic enzymes. Organ distribution and pharmacokinetic study in albino rats was performed to establish the targeting potential of optimized formulation in the colon.  相似文献   

14.
Abstract

This study examined whether oral administration of dasatinib to the rats with imatinib led to any pharmacokinetic interactions. Twenty-four rats were divided randomly into three groups, imatinib group (imatinib 25?mg/kg, n?=?8), dasatinib group (dasatinib 15?mg/kg, n?=?8) and co-administration group (dasatinib 15?mg/kg and imatinib 25?mg/kg, n?=?8). The concentration of imatinib and dasatinib in rat plasma was determined by a sensitive and simple UPLC–MS/MS method. There was statistical pharmacokinetics difference for imatinib in the imatinib group and co-administration group, when co-oral administration imatinib with dasatinib, MRT(0–t) increased (p?<?0.01). There was statistical pharmacokinetics difference for dasatinib in the dasatinib group and co-administration group, when co-oral administration dasatinib with imatinib, Cmax and AUC increased (p?<?0.01), CL and V decreased (p?<?0.01). These data indicate dasatinib could slightly influence the pharmacokinetic profile of imatinib in rats, and imatinib could influence the pharmacokinetic profile of dasatinib in rats, which might cause drug–drug interactions when using imatinib with dasatinib.  相似文献   

15.
A biodegradable, composite bone graft, composed of chitosan microspheres embedded in calcium sulfate, was evaluated in vitro for point-of-care loading and delivery of antibiotics and growth factors to prevent infection and stimulate healing in large bone injuries. Microspheres were loaded with rhBMP-2 or vancomycin prior to mixing into calcium sulfate loaded with vancomycin. Composites were evaluated for set time, drug release kinetics, and bacteriostatic/bactericidal activity of released vancomycin, induction of ALP expression by released rhBMP-2, and interaction of drugs on cells. Results showed the composite set in under 36 min and released vancomycin levels that were bactericidal to S. aureus (>MIC 8–16 μg/mL) for 18 days. Composites exhibited a 1 day-delayed release, followed by a continuous release of rhBMP-2 over 6 weeks; ranging from 0.06 to 1.49 ng/mL, and showed a dose dependent release based on initial loading. Released rhBMP-2 levels were, however, too low to induce detectable levels of ALP in W20-17 cells, due to the affinity of rhBMP-2 for calcium-based materials. With stimulating amounts of rhBMP-2 (>50 ng/mL), the ALP response from W-20-17 cells was inhibited when exposed to high vancomycin levels (1,800–3,600 μg/mL). This dual-delivery system is an attractive alternative to single delivery or preloaded systems for bone regeneration since it can simultaneously fight infection and deliver a potent growth factor. Additionally, this composite can accommodate a wide range of therapeutics and thus be customizable for specific patient needs, however, the potential interactive effects of multiple agents must be investigated to ensure that functional activity is not altered.  相似文献   

16.
The multifunctional strontium (Sr)-substituted hydroxyapatite microsphere was prepared via hydrothermal method, in which the luminescent and controlled drug release functions can be realized. The structure and morphology of the as-prepared microspheres were studied by using XRD, FTIR, SEM, TEM, HR-TEM, BET method. The optical properties was investigated by using photoluminescence (PL) and XPS measurement. Then, the as-prepared multifunctional microspheres were performed as a drug delivery carrier using vancomycin as a model drug. The experimental results show that the composition, morphology, luminescent properties and drug storage/release behaviour were obviously influenced by the amount of Sr. The microspheres with Sr2+/(Ca2+ + Sr2+) = 0.3 of Sr substitution showed the maximum specific surface area, best pore structure and strongest PL intensity. All the samples presented remarkable sustained drug release kinetics. In addition, the PL intensity of SrHA in the drug delivery system increased with the cumulative release time (amount) of vancomycin, which would make the drug release might be possibly tracked by the change of the luminescent intensity. Our study indicated a potential prospect that the fabricated multifunctional SrHA mesoporous microspheres might be applied in the field of bone regeneration and drug delivery.  相似文献   

17.
In this study, a folate-modified–chitosan-coated liposome (FCCL) was prepared for tumor-targeted drug delivery. The folate–chitosan conjugates were characterized using 1H NMR and infrared spectrum analysis. The properties of folate–chitosan-coated liposomes (FCCLs) were studied and compared with those of traditional liposomes and chitosan-coated liposomes (CCLs). FCCLs were spherical in shape with a classic core–shell structure. Compared with conventional liposomes, FCCLs had larger size (average diameter: 182.0 nm), higher zeta potential (10.1 mV), prolonged drug release behaviors (55.76 % after 24 h), and better physical stability when stored at 25 °C, all similar to the properties of CCLs. With fluorescein as a model drug, fluorescein-loaded liposomes, CCLs, and FCCLs were prepared and their tumor targeting ability was evaluated according to the in vitro cellular uptake of fluorescein loaded nanoparticles by MCF-7 and HUVEC cells. Results demonstrated that FCCLs had a significant higher uptake by folate receptor positive cells (MCF-7) as compared to traditional liposomes and CCLs, which indicated that the FCCLs were promising nano-carriers for tumor-targeted drug delivery.  相似文献   

18.
This investigation is to find a prolonged or delayed drug release system, exclusively for the treatment of hepatitis‐B to reduce the side effects, which arise when conventional solid dose forms are administered. To pursue this goal, lamivudine‐loaded Eudragit‐coated pectin microspheres have been formulated employing water/oil (W/O) emulsion evaporation strategy. The formulation was optimised using a 34 factorial design. A drug to polymer ratio of 1:2, the surfactant of 1 ml, the volume of 50 ml of processing medium with a stirring speed of 2500 rpm were found to be the optimal parameters to obtain the lamivudine‐loaded Eudragit‐coated pectin microspheres formulation with a high drug entrapment efficiency of 89.44% ± 1.44%. The in vitro release kinetics of lamivudine was a suitable fit to the Higuchi model, indicating a diffusion‐controlled release with anomalous transport. The obtained microspheres were then subjected to different characterisation studies, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X‐ray diffraction (XRD). The results of this study clearly indicate that Eudragit‐coated pectin microspheres could be the promising controlled release carriers for colon‐specific delivery of lamivudine in the presence of rat cecal content.  相似文献   

19.
Semi-interpenetrating network microspheres of chitosan-(dextran-g-acrylamide) were prepared by emulsion-crosslinking method using glutaraldehyde (GA) as a crosslinking agent. Graft copolymerization of dextran with acrylamide (Dx-g-AAm) was carried out by aqueous free-radical polymerization using ceric ammonium nitrate (CAN) as initiator. The grafting efficiency was found to be 92%. Theophylline (TH), antiasthmatic drug, was successfully encapsulated into semi-INP microspheres by varying the ratio of Dx-g-AAm and amount of GA. The laser light scattering technique shows that the particles size increased with increasing amount of graft copolymer and decrease with increasing amount of GA. The % encapsulation efficiency was found to vary between 50 and 78. MPs were characterized by FTIR spectroscopy and differential scanning calorimetry (DSC) techniques to confirm the graft copolymer, formation of semi-IPN structure of MPs and molecular distribution of the drug molecules in the polymer matrix. In vitro release studies of TH from these matrices have been investigated at Ph 1.2 and 7.4 media and the slow release were extended up to 18 h at 37°C. The release rates were fitted to an empirical equation to estimate the diffusion exponent n, which indicated that the release from the MPs follows non-Fickian type.  相似文献   

20.
The novel amphiphilic derivatives of Methotrexate–chitosan oligosaccharide (MTX–CHO) with different molar feeding ratios of MTX were synthesized. The degree of MTX substitution ranged from 4.47 to 13.5 %. MTX–CHO copolymer formed micelles with an average size of 134.6 ± 14.52 to 236.6 ± 30.01 nm, and zeta potential of 20 ± 5 to 16.8 ± 7.74 mV. The critical micelle concentration was found to range from 125 to 0.56 mg/l. Analysis of micelles with different degree of substitutions (DSs) revealed that the size of micelles decreased by increasing DS while zeta potential was reduced. Release study indicated that drug content had effect on the release rate. With increasing amount of loaded drug in the micelle, release rate was decreased. Drug loaded and unloaded MTX–CHO micelles showed significant cytotoxicity on MDA-MB-231. Loaded micelle was more effective than unloaded one which indicated that conjugation could reduce efficacy of MTX. The viability of MDA-MB-231 in presence of drug loaded micelles was significantly decreased and cell viability at 1 µg/ml was 45.17 ± 9 % while the viability of unloaded micelles was 91.86 ± 9.88. These phenomena make MTX–CHO micelles as a good candidate for hydrophobic anticancer drug carrier.  相似文献   

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