氧氟沙星/壳聚糖凝胶制备及其缓释性能

壳聚糖为原料,氧氟沙星为模型药物,戊二醛为交联剂制成凝胶,应用紫外分光光度法测定氧氟沙星的含量,对该载药凝胶进行体外的缓释实验。该凝胶能够用于负载并释放氧氟沙星,这为改善氧氟沙星使用途径提供了实验基础。     

缓释型驱蚊纳米胶囊的制备及性能研究

以壳聚糖、三聚磷酸钠为壁材,长效驱蚊剂避蚊胺为芯材,采用离子凝胶法制备驱蚊纳米胶囊。研究不同制备条件对纳米胶囊粒径大小和包覆率的影响;利用扫描电镜、透射电镜、红外光谱表征了纳米胶囊的结构与形貌;采用热重分析表征纳米胶囊热稳定性能并研究其在不同温度下的缓释性能。结果表明,制备的驱蚊纳米胶囊呈球状,粒径大小为264.7 nm,包覆率为65.25%,具有良好的缓释性能和热稳定性能。     

缓释型驱蚊纳米胶囊的制备及性能研究

以壳聚糖、三聚磷酸钠为壁材,长效驱蚊剂避蚊胺为芯材,采用离子凝胶法制备驱蚊纳米胶囊。研究不同制备条件对纳米胶囊粒径大小和包覆率的影响;利用扫描电镜、透射电镜、红外光谱表征了纳米胶囊的结构与形貌;采用热重分析表征纳米胶囊热稳定性能并研究其在不同温度下的缓释性能。结果表明,制备的驱蚊纳米胶囊呈球状,粒径大小为264.7 nm,包覆率为65.25%,具有良好的缓释性能和热稳定性能。     

基于壳聚糖的缓释材料应用研究进展

药物缓释材料种类繁多,壳聚糖因其自身多方面的特性而成为理想的药物缓释载体。文章简要介绍了壳聚糖的缓释机理,且因壳聚糖本身拥有的特殊药理作用,它可用于抗炎、抗癌、抗肺结核及基因类药物载体,模型实验显示均收到了较好的药物缓释效果和相应的治疗效果,因此,本文主要介绍了壳聚糖作为不同药物缓释载体的应用研究进展。     

壳聚糖缓释微球的制备与表征

以壳聚糖(Chitosan)、戊二醛(Glutaraldehyde)、尿素(Urea)为主要原料,采用乳化-化学交联法制备尿素-壳聚糖缓释微球.通过红外光谱测试,分析缓释微球的结构特征;通过扫描电镜测试,观察微球的微观形貌;通过交联度测试确定戊二醛的最佳用量;通过缓释测试,测定壳聚糖微球的缓释效果.结果表明:采用乳化-...     

基于壳聚糖的先进材料I.药物缓释体系

作为一种天然高分子多糖,壳聚糖由于其来源广泛,具有良好的生物降解性、生物相融性和无毒性等特性,成为备受青睐的原材料.文章简要介绍了2000年以来在基于壳聚糖的先进材料的制备及应用方面的研究进展.主要涉及基于壳聚糖的药物缓释体系.     

基于壳聚糖的先进材料 Ⅰ.药物缓释体系

作为一种天然高分子多糖,壳聚糖由于其来源广泛,具有良好的生物降解性、生物相融性和无毒性等特性,成为备受青睐的原材料。文章简要介绍了2000年以来在基于壳聚糖的先进材料的制备及应用方面的研究进展。主要涉及基于壳聚糖的药物缓释体系。     

壳聚糖缓释体系研究进展

综述了壳聚糖在缓释系统方面的最新研究进展。包括壳聚糖衍生物缓释体系的研究、壳聚糖缓释体系在医药系统的应用和吸附-控释复合体系的研究,重点介绍了壳聚糖衍生物缓释体系的研究,壳聚糖衍生物缓释体系分为壳聚糖衍生物缓释微球、壳聚糖纳米粒、壳聚糖缓释片、壳聚糖缓释微囊、壳聚糖缓释膜和壳聚糖水凝胶缓释体的研究等六个部分。壳聚糖缓释体系作为一项新技术在医药体系具有广泛的应用前景。     

γ-聚谷氨酸/壳聚糖纳米胶囊在香精缓释中的应用研究

制备了香精-γ-聚谷氨酸/壳聚糖纳米胶囊,并研究其缓释性能。以γ-聚谷氨酸和壳聚糖为原料、茉莉香精为模型,利用聚电解质自组装法在常温常压下制备纳米胶囊,利用纳米粒度激光分析仪对其平均粒径和粒径分布进行测定,选出最优的条件,然后利用电子鼻对其进行缓释性能测定。当乳化剂（Teewen-80）添加量为10%、乙醇添加量为0.5mL、香精添加量为2%时,得到的茉莉香精纳米胶囊的平均粒径为153nm,粒度分布系数为0.208,Zeta电位为35.2mV。该茉莉香精纳米胶囊在室温下具有明显的缓释能力。因此,以生物材料γ-聚谷氨酸和壳聚糖为原料制备的香精纳米胶囊粒度均一,可以应用于香精缓释。     

超临界抗溶剂技术制备缓释胶囊的研究进展

介绍了超临界抗溶剂技术制备缓释胶囊的原理、方法及研究进展,分析了颗粒性质的影响因素,总结了超临界抗溶剂技术在制备缓释胶囊方面存在的问题及展望。     

甲壳素及其衍生物在缓释药物中的应用

介绍了甲壳素及其衍生物制备缓释药物的常见方法以及影响药物释放速率的主要因素     

医用多孔支架材料的制备及缓释性能分析

采用溶液浇铸法制备了聚己内酯⁃姜黄素（PCL⁃CUR）多孔支架,通过冷场发射扫描电子显微镜（SEM）和热重分析仪（TG）等对支架材料的孔隙率、载药量及缓释性等进行了表征,并分析了其体外释药模型。结果表明,CUR在支架材料中含量为2 %（质量分数,下同）,PCL在醋酸中浓度为10 %,壳聚糖在支架材料中含量为2.86 %时,其释药模型符合1级方程,支架材料的孔隙率达95 %以上,载药量达到1.63 %,在PBS缓冲液中90 h内CUR累计释放率为76.2 %;其他配方的支架材料孔隙率均为95 %以上,90 h内CUR累计缓释率在60 %~87 %之间,表明制得的支架材料具有较理想的孔隙率和明显的CUR药物缓释作用,在组织工程领域有较好的应用前景。     

Effect of preparation method and characteristics of chitosan on the mechanical and release properties of the prepared capsule

The objective of this study is to elucidate the effect of preparation method and the characteristics of chitosan used on the mechanical and release properties of the prepared capsule. The characteristics of the chitosan explored include molecular weight (1.8, 5.6, 20.2, and 31.8 × 10⁵ Dalton) and chain flexibility parameter (B), which was manipulated by a varying degree of deacetylation (DD, 67.9, 81.3, 90.5, and 92.2%), and sodium chloride concentration (0 or 0.3%). The orifice method was used to encapsulate hemoglobin, whereas complex coacervation was used to encapsulate the bovine serum albumin (BSA). The axial ratio was measured to characterize the appearance of the capsule. Break strength was used as an index of mechanical strength. Release percent of protein was used as a pore size indicator. The results show axial ratio and hemoglobin release percent of the capsule prepared by the orifice method increased with the increase of the chain flexibility parameter (B), but decreased with the increase of the chitosan molecular weight. However, break force behaved just opposite from that of the axial ratio and release percent of hemoglobin. The capsule cannot be prepared from 92.2% DD chitosan. Break strength and BSA release percent of the capsule prepared by complex coacervation did not vary with different DD, molecular weight of chitosan, and sodium chloride concentration. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 161–169, 1997     

Synthesis of pH-responsive isolated soy protein/carboxymethyl chitosan microspheres for sustained pesticide release

In order to improve the utilization rate of avermectin (AVM), a complex was prepared by electrostatic self-assembly using isolated soy protein (ISP) and carboxymethyl chitosan (CMCS) for loading AVM to obtain ISP/CMCS@AVM microspheres. The encapsulation efficiency (EE), sustained release property, ultraviolet (UV) protective ability, and toxicity of the microspheres were evaluated, and the release kinetics of AVM from the microsphere at different pHs were investigated. The results demonstrated that the average particle size of ISP/CMCS@AVM was 283.95 nm, and the EE reached 88.42% for AVM after denaturation. After 70 h of exposure to UV light, the residual rate of AVM in ISP/CMCS@AVM was 78.12%, which was significantly higher than 35.18% in the AVM emulsion. Moreover, the formulation imparted pH sensitivity and sustained-release property to AVM and was consistent with the Korsmeyer–Peppas model, controlled by Fick diffusion. Finally, the insecticidal toxicity of ISP/CMCS@AVM did not differ significantly from that of unmodified AVM. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48358.     

Encapsulation of salicylic acid in acylated low molecular weight chitosan for sustained release topical application

Acylated low molecular weight chitosan was used to encapsulate salicylic acid (SA) for sustained release in topical delivery. Chitosan nanoparticles were prepared from the depolymerization of commercial chitosan and further acylated with short alkyl chains. The successful acylation of butyryl chitosan [low molecular weight chitosan (LMWC)‐B] were proved by Fourier transform infrared (FTIR) and ¹H‐NMR. Successful encapsulation of SA was observed by the shift of amide I band from 1648 cm^?1 in LMWC‐B to 1641–1633 cm^?1 in SA‐loaded LMWC‐B in FTIR analysis, which further confirmed with the size increment from dynamic light scattering and transmission electron microscopy analyses by comparing its unencapsulated LMWC‐B. SA release from LMWC‐B studied by Franz diffusion experiment followed Korsmeyer–Peppas model where the release component n value (0.502) indicated diffusion and polymer swelling were involved in release mechanism. The slow release study of SA showed the acylated chitosan exhibited sustained release property toward SA. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45273.     

Preparation of porous chitosan/agarose microsphere and its R‐phycoerythrin release properties

The chitosan microspheres (CS‐CL) were prepared by suspension crosslinking method and used as carriers of R‐phycoerythrin (R‐PE). In this study, R‐PE was loaded in the microspheres and released in vitro. The effects of pH value, temperature, ionic strength, and R‐PE concentration on loading efficiency and release behavior were discussed. A novel microsphere that contained agarose (CS‐AR MP) was prepared and the basic loading and releasing behavior for R‐PE of this kind of new microspheres were also investigated. The results showed that all these chitosan microspheres have the ability to control‐release R‐PE. The addition of agarose may somewhat accelerate the release rate of R‐PE from microspheres and reduce the capacity of adsorption for R‐PE. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2759–2766, 2007     

酸化凹凸棒石/海藻酸复合材料的制备及其缓释性能

以海藻酸钠 (SA) 和酸化凹凸棒石 (H⁺-ATP) 为原料,运用溶液共混法制备了一种具有优良缓释性能的复合材料,并以其为基质材料制备了双氯芬酸钠 (DS) 缓释片.利用SEM、FTIR和XRD对复合材料形貌和结构进行了表征,考察了酸改性剂浓度、H⁺-ATP用量和复合时间对复合材料缓释性能的影响,以获得最佳复合工艺.结果表明,当用12 mol·L^-1盐酸酸化的ATP量占复合物总量60%时,复合缓释片在体外模拟肠液中缓释性能最佳.与单一海藻酸缓释片相比,复合缓释片2 h的累积释放率由42.6%下降到23.7%,有效改善了"突释"效应.释放动力学研究表明,复合缓释片的释药行为可以用Ritger-Peppas方程很好地拟合,释药速率受骨架溶蚀和药物扩散双重控制.H⁺-ATP的加入显著改善了海藻酸的缓释性能.     

低CMC纳米载体PEGMA-b-PLLA-b-PCL的制备及其药物缓释性能

以ε-己内酯（ε-CL）为疏水原料，聚乙二醇甲醚甲基丙烯酸酯（PEGMA）为亲水原料，通过引入亲疏水性过渡原料L-丙交酯（LLA），利用可逆加成-断裂链转移法（RAFT）制备了超低临界胶束浓度（CMC）的聚乙二醇甲醚甲基丙烯酸酯-聚丙交酯-聚己内酯（PEGMA-b-PLLA-b-PCL）。通过FTIR、1HNMR、GPC、DLS和SEM对聚合物的结构、相对分子质量（简称分子量）及粒径进行测定，用界面张力法测得PEGMA-b-PLLA-b-PCL 胶束溶液的CMC，用溶剂挥发法负载姜黄素（CUR）制备载药胶束溶液，并计算其载药量和包封率，进一步考察载药胶束溶液在不同环境下的释药能力。结果表明，聚合物相对分子质量（简称分子量）为1220~8782，粒径为28~180 nm，且最低CMC为0.62 μg/mL（pH=7.4）。载药胶束的载药量和包封率最高可达12.6%和78 .0% (pH=7.4)，且药物释放可在15 d内完成，在pH=5环境下释放量最高可达45.53%。     

Preparation and characterization of novel semi‐interpenetrating 2‐hydroxyethyl methacrylate‐g‐chitosan copolymeric microspheres for sustained release of indomethacin

A novel semi‐interpenetrating (semi‐IPN) graft copolymer of 2‐hydroxyethyl methacrylate (HEMA) with chitosan (CS) has been prepared in the form of microspheres, using water‐in‐oil (W/O) emulsion technique. Microspheres were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X‐ray diffractometry (X‐RD) to confirm the crosslinking and polymorphism of indomethacin (IDM). The X‐RD and DSC techniques indicated a molecular‐level dispersion of IDM in the IPN matrix. Scanning electron micrographs (SEM) taken at the cross section of the microspheres have shown rough surfaces around the microspheres. The sustained release characteristics of the matrices for IDM, an anti‐inflammatory drug, were investigated in pH 7.4 media. Particle size and size distribution of the microspheres were studied by laser light diffraction particle size analyzer. The drug was released in a sustained manner for up to 12 h. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

CS／PLLA／TPP纳米微胶囊的制备及体外释放

主要考察负载雷帕霉素（Rapaymcin,RAPA）的壳聚糖（Chitosan,CS）微球在加入左旋聚乳酸（L—polylactic acid,PLLA）时的载药量,包封率及在不同溶剂中的缓释性能。采用三聚磷酸钠（Sodium tripolyphosphate,TPP）作为离子交联剂,应用离子凝聚法制备CS／PLLA／TPP纳米微胶囊,用透射电镜和粒径分析仪进行了表征。结果表明：离子凝胶法可以得到粒径约300—400nm均匀分散的壳聚糖纳米微胶囊;微胶囊包封率可达84．25％,微胶囊载药量可达30．22％,雷帕霉素在不同溶剂中的缓释性能有很大不同。