复合海绵的细胞毒性及生物相容性研究

目的评价复合海绵的细胞毒性及生物相容性。方法采用MTT实验考察复合海绵浸提液对L929细胞增殖的抑制作用;扫描电镜观察L929细胞在海绵表面的生长情况;利用分光光度法测定其对鼠抗凝血的溶血作用;在鼠肝脏造成活性出血创面,用复合海绵或明胶海绵止血后,光镜观察海绵与肝脏组织的相容性。结果复合海绵浸提液对L929细胞增殖无抑制作用,该细胞可在海绵表面正常生长;无溶血作用,组织相容性较好。结论复合海绵无细胞毒性,且具有良好的生物相容性。     

透明质酸修饰姜黄素壳聚糖纳米粒的制备及初步细胞毒性考察

采用离子交联法制备姜黄素壳聚糖纳米粒,然后通过共价连接将透明质酸连接到纳米粒表面。所得透明质酸修饰姜黄素壳聚糖纳米粒呈球形,平均粒径(205.3±11.4)nm,包封率和载药量为42.7%和28.4%,透明质酸的平均结合率为39%。体外细胞毒性试验显示,该制品对高表达CD44受体的A549细胞增殖的抑制率明显高于未修饰纳米粒和游离药物。而对于CD44低表达的Hep G2细胞,修饰和未修饰纳米粒的抑制率相当。     

载柚皮素壳聚糖纳米粒的制备及其体外细胞评价

目的：制备柚皮素壳聚糖纳米粒,初步探讨其对人肺腺癌细胞A549的细胞毒性和细胞摄取。方法：以壳聚糖和鱼精蛋白作为载体材料,采用离子胶凝法制备柚皮素壳聚糖纳米粒,透射电镜（TEM）观察其形态,马尔文激光粒度仪测定其粒径、分散度（PDI）和Zeta电位,离心法测定其包封率和载药量,采用恒温振荡水浴法对柚皮素壳聚糖纳米粒进行体外释放度研究,最后采用人肺癌细胞系A549细胞进行了细胞毒性、细胞摄取研究。结果：柚皮素壳聚糖纳米粒为球形或类球形粒子,结构完整,大小均一、球形度好,分散均匀,PDI、粒径、Zeta电位和包封率分别为0.268,139 nm、+15.7 mV和83.34%,柚皮素壳聚糖纳米粒体外释放呈缓释,24 h累积释放量达到了80%以上,体外释药过程用Higuchi方程拟合较好。MTT试验显示不同浓度的壳聚糖纳米粒和细胞作用72 h后,细胞活力均大于95%,本文所制备的壳聚糖纳米粒无细胞毒性。细胞摄取试验表明载FITC的壳聚糖纳米粒和A549细胞作用3 h后,可明显看到大量带绿色荧光的纳米粒穿过细胞膜进入细胞。结论：离子凝胶法成功制得粒径较小的柚皮素壳聚糖纳米粒,具有缓释性好,毒性小,壳聚糖纳米粒摄取率较高,可大大提高药物的利用率,具有广泛的应用前景。     

磁性壳聚糖微球制备及生物相容性的研究

目的:制备5-氟尿嘧啶磁性壳聚糖微球并评价空载磁性壳聚糖微球的生物相容性。方法:采用乳化交联法制备5-氟尿嘧啶磁性壳聚糖微球并优化制备工艺,采用扫描电镜和振动样品磁强计(VSM)对微球进行表征;四噻唑蓝法观察细胞增殖情况,评估磁性壳聚糖微球的体外细胞毒性;溶血实验和血常规检查评估磁性壳聚糖微球的血液相容性;植埋实验评估磁性壳聚糖微球的组织相容性。结果:经过优化后的5-氟尿嘧啶磁性壳聚糖微球包封率和载药量分别为70.2%和12.3%,Z-均粒径为1 479.6 nm,饱和磁化度为4.79 emu.g-1,微球形态良好、均匀圆整;自制空载磁性壳聚糖微球体外细胞相容性符合要求,显示出良好的血液相容性和体内组织相容性。结论:优化了5-氟尿嘧啶磁性壳聚糖微球的制备工艺,制备的空载磁性壳聚糖微球具有很好的生物相容性。     

聚（2-乙基-2-噁唑啉）-聚乳酸胶束的血液相容性和细胞相容性研究

合成的二嵌段共聚物聚（2-乙基-2-噁唑啉）-聚乳酸（PEOz-PLA）可自组装形成胶束,其在药物输送领域的应用与口俱增。然而,其与血液和细胞之间的相互作用迄今未知。本研究拟对PEOz-PLA胶束的血液相容性和细胞相容性进行评价,为PEOz-PLA胶束的潜在应用提供数据支持。通过溶血、凝血时间、血小板激活以及与白蛋白的相互作用评价了PEOz-PLA胶束的血液相容性。结果表明,PEOz-PLA胶束的血液相容性良好。SRB的实验结果表明,PEOz-PLA胶束与KBv细胞孵育后并未出现明显的细胞毒性,显示出良好的细胞相容性。总之,PEOz-PLA胶束是血液和细胞相容的药物载体,可用于静脉给药。     

丝素蛋白自组装纳米粒的制备、理化表征及细胞相容性研究

本研究旨在制备丝素蛋白纳米粒(SF-NPs),并对制备得到的纳米粒的理化性质及细胞相容性进行评价。采用优化简易的去溶剂化法制备SF-NPs。通过单因素的处方筛选,如丝素蛋白(SF)溶液的浓度、SF溶液和有机溶剂的比例、超声功率及时间、不同有机相的种类,优化了制剂处方,并对最优处方的粒径分布、多分散性指数(PDI)、zeta电位、形态及稳定性进行了表征。通过CCK-8及细胞活/死染色Calcein-AM/PI评估了SF-NPs的体外细胞相容性。实验结果表明,当SF浓度为20 mg·mL^-1、水相和丙酮的体积比为1∶6、超声功率为80 W、超声时间为3 min时,制备得到的SF-NPs最优。本研究制备得到的SF-NPs为类球形,粒径分布狭窄,平均粒径为144.8 nm, PDI为0.174,zeta电位为-27.35 mV。细胞相容性实验结果表明, SF-NPs具有优异的细胞相容性,可促进细胞的增殖。综上表明,通过去溶剂法制备得到SF-NPs具有均一的粒径及良好的生物相容性,在药物递送领域具有较大的应用前景。     

壳聚糖DCX-16的初步安全性评价

目的 :初步评价新壳聚糖衍生物DCX -16的安全性。方法 :通过对小鼠腹腔注射壳聚糖DCX -16后进行耐量试验、家兔眼刺激性及肌肉刺激性试验 ,以及用噻唑蓝比色法观察壳聚糖DCX -16对体外培养的3T3成纤维细胞增殖的影响等研究 ,评价壳聚糖DCX -16的安全性。结果 :小鼠对壳聚糖DCX -16的日最大耐受量为3. 0g/kg ;壳聚糖DCX -16对家兔眼睛及肌肉均无刺激性作用 ;3T3细胞经壳聚糖DCX -16作用后生长良好 ,增殖率在第2、3、4d时与对照组无显著性差异。结论 :新型壳聚糖DCX -16具有一定的安全性。     

三种不同载体材料体外生物相容性的比较

目的探讨纳米晶羟基磷灰石胶原复合材料(NHAC)、非纳米晶羟基磷灰石胶原复合材料(HAC)和珊瑚羟基磷灰石(CHA)的体外生物相容性,为组织工程提供理想的细胞基质载体材料。方法将人骨髓基质干细胞分别与上述三种载体材料体外复合培养,应用倒置显微镜、扫描电镜、四唑盐比色试验(MTT法)及碱性磷酸酶(ALP)活性测定,对材料上复合培养的细胞进行形态学和功能测定。结果骨髓基质干细胞能在NHAC和CHA两种材料上良好地黏附、增殖和生长。细胞的活性和碱性磷酸酶活性未受到材料的影响;而HAC不利于人骨髓基质干细胞的黏附、增殖,并使碱性磷酸酶活性降低。结论NHAC和CHA两种材料具有良好的生物相容性,可作为骨组织工程理想的骨替代材料;HAC不适合做细胞外基质。     

玉米醇溶蛋白黏附控释片的制备及体外评价和体内药动学研究

目的：制备玉米醇溶蛋白黏附控释片,考察其体外黏附性能和释药行为以及体内药动学特性。方法：以玉米醇溶蛋白为骨架和黏附材料,5-氟尿嘧啶为模型药物,制备胃肠道生物黏附控释片,并将其与市售普通片剂和自制控释片进行体外黏附性能和释药行为以及大鼠体内药动学比较。结果：用玉米醇溶蛋白包衣的5-氟尿嘧啶黏附控释片具有良好的组织黏附性,体外释放在12小时之内符合零级释放,达到了控释目的,且与参比制剂相比,其在大鼠胃肠道的滞留时间更长,药物释放更平稳,缓释效应明显。结论：玉米醇溶蛋白对胃肠道黏膜具有良好的生物黏附性,将其用作包衣材料制各黏附控释片,可实现药物在胃肠道的缓控释。     

MTT法评价4种医用材料的细胞毒性

目的 研究4种医用材料的细胞毒性.方法 按照GB/T16886.5-2003/ISO10993-5:1999的体外细胞毒性评价方法要求,用MTT比色法评价4种医用材料的细胞毒性.结果 4种医用材料均表现出较高的细胞相对增殖率,其细胞毒性为1级.结论 4种医用材料对细胞形态、生长和增殖不构成损害,无明显细胞毒性,具有良好...     

Cholic acid modified N-(2-hydroxy)-propyl-3-trimethylammonium chitosan chloride for superoxide dismutase delivery

A series of novel amphiphilic chitosan derivatives, cholic acid modified N-(2-hydroxy)-propyl-3-trimethylammonium chitosan chloride (HTCC-CA) with different quaternization degrees and cholic acid substitutions were synthesized in this study. HTCC-CA is biocompatible and forms particles in aqueous solution. The binding with superoxide dismutase (SOD) at pH 6.8 destroys the original aggregates of HTCC-CA and produces smaller SOD/HTCC-CA complex nanoparticles via electrostatic and hydrophobic interactions. The SOD loading efficiency and loading capacity of HTCC-CA can reach to more than 90% and 45%, respectively. Confocal laser scanning microscopy observation and flow cytometry analysis reveal that SOD/HTCC-CA complex nanoparticles greatly enhance the cellular internalization of the loaded SOD. The SOD activities and malonaldehyde concentrations in the serum and organs of the rats, administrated intravenously with free SOD, free HTCC-CA, and SOD/HTCC-CA nanoparticles, were assayed to evaluate the antioxidant efficiency in vivo. The results demonstrate that free HTCC-CA is effective to scavenge superoxide radicals in the blood circulation and SOD/HTCC-CA nanoparticles have better antioxidant efficiency than free SOD as well as free HTCC-CA.     

Preparation, characterization and protein loading of hexanoyl-modified chitosan nanoparticles

Hexanoyl chitosan was synthesized through a coupling reaction between chitosan and hexanoic anhydride. Proton nuclear magnetic resonance (¹HNMR) and fourier-transform infrared (FTIR) spectroscopy studies showed the formation of hexanoyl chitosan. The nanoparticles of hexanoyl chitosan were prepared through ionotropic gelation with tripolyphosphate (TPP) followed by sonication. The hexanoyl chitosan-TPP nanoparticles exhibited uniform spherical shape with smooth surface as observed by atomic force microscopy and transmission electron microscopy. The particle size of nanoparticles was between 54.1 to 724 nm with a mean diameter of 324 nm. At 0.2, 0.4, and 0.6 mg/mL bovine serum albumin initial concentration, the encapsulation efficiency and loading capacity of hexanoyl-chitosan-TPP nanoparticles were 58.2, 44.5, and 28.1%, and 14.1, 23.4, and 30.3%, respectively.     

Evaluation of ketorolac tromethamine microspheres by chitosan/gelatin B complex coacervation

Microspheres (MS) of Ketorolac Tromethamine (KT) for oral delivery were prepared by complex coacervation (method-1) and simple coacervation (method-2) methods without the use of chemical crossalinking agent (glutaraldehyde) to avoid the toxic reactions and other undesirable effects of the chemical cross-linking agents. Alternatively, ionotropic gelation was employed by using sodium-tripolyphosphate (Na-TPP) as cross linking agent. Chitosan and gelatin B were used as polymer and copolymer respectively. All the prepared microspheres were subjected to various physico-chemical studies, such as drug-polymer compatibility by Thin Layer Chromatography (TLC) and Fourier Transform Infra Red Spectroscopy (FTIR), surface morphology by Scanning Electron Microscopy (SEM), frequency distribution, encapsulation efficiency, in-vitro drug release characteristics and release kinetics. The physical state of drug in the microspheres was determined by Differential Scanning Calorimetry (DSC) and X-ray powder Diffractometry (XRD). TLC and FTIR studies indicated no drug-polymer incompatibility. All the MS showed release of drug by a fickian diffusion mechanism. DSC and XRD analysis indicated that the KT trapped in the microspheres existed in an amorphous or disordered-crystalline status in the polymer matrix. It is possible to design a controlled drug delivery system for the prolonged release of KT, improving therapy by possible reduction of time intervals between administrations.     

壳聚糖凝胶的含量测定及其对化疗性静脉炎的疗效评价

目的 测定壳聚糖凝胶中壳聚糖的含量,并评价该凝胶对化疗性静脉炎的疗效.方法 采用茚三酮显色法,结合紫外-可见光谱分析,对壳聚糖凝胶中壳聚糖进行定量分析;使用家兔耳缘静脉炎模型,评价壳聚糖凝胶对化疗性静脉炎的疗效.结果 在4.0～40.0μ g/ml范围内,壳聚糖浓度与吸光值线性关系良好(r=0.9969),平均回收率为101.80％.通过LSD-t检验后,壳聚糖凝胶对化疗性静脉炎的疗效与阳性对照药效果比较差异无统计学意义(t=0.939,P=0.362).结论 建立的茚三酮显色-紫外可见分光光度法可用于测定自制壳聚糖凝胶的含量;壳聚糖凝胶具有治疗或加速化疗性静脉炎康复的作用.     

Biocompatible hydrogel based on aldehyde-functionalized cellulose and chitosan for potential control drug release

The present study aimed to prepare cellulose-based biodegradable hydrogel that revealing a potential control of drug release. To achieve this purpose, activation of cellulose was achieved firstly by pretreatment stage using ZnCl₂. Then, selective oxidation of activated cellulose was performed by using sodium periodate to achieve cleavage of the bond between C2 – C3 in the glucose unit generating two active aldehyde groups. The modified cellulose (Dialdehyde cellulose, DAC) was reacted with chitosan, in different molar ratios, via condensation between aldehyde and primary amine groups situated onto cellulose and chitosan, respectively. The activated cellulose, DAC, and produced hydrogels were characterized via FTIR, XRD, and SEM to detect the emerging functional groups as well as the variation of crystallinity and surface morphology features of activated cellulose, DAC, and hydrogels. The swelling capacities of hydrogels showed the optimum value at pH = 7.0. The prepared hydrogels cytotoxicity was investigated toward normal skin fibroblast by MTT assay. It was found that the cells treated with chitosan/DAC hydrogels with ratio 1:1, 1:2, and 1:3 affected by 1.3, 1.8, and 0%, respectively. Streptomycin was incorporated in the prepared hydrogels and its release was evaluated. The DAC ratio was played a key role in controlling the release process. Moreover, further studies were carried out on chitosan (PDB: 2RVA) to evaluate its potential interaction with DAC and streptomycin with binding energies ?4.4 and - 4.3 kcal/mol with short bond lengths 1.3 and 1.944 Å, respectively.     

Preparation and in vitro evaluation of bFGF-loaded chitosan nanoparticles

The objective of our study was to prepare and characterize basic fibroblast growth factor (bFGF)-loaded nanoparticles. Protein-loaded chitosan nanoparticles were obtained by ionotropic gelation process based on the interaction between chitosan and tripolyphosphate (TPP). The protein-loading capacity and encapsulation efficiency were 0.021% and 27.388%, respectively. The bFGF-loaded nanoparticles have a mean diameter of 424 nm, a narrow size distribution, spherical shape and positive surface charges. In vitro release showed that the extent of release was 68% at 24 hr. The protein integrity was investigated by SDS-PAGE analysis that confirmed protein integrity was not affected by the encapsulation procedure and release conditions.     

Hydrophobically modified carboxymethyl chitosan nanoparticles targeted delivery of paclitaxel

Specific targeting of tumor cells to achieve higher drug levels in tumor tissue and to overcome the side effects is the major goal in cancer therapy. Nanoparticles encapsulating a hydrophobic core in their nanoreservoir structure were developed as a carrier for a water-insoluble drug, paclitaxel. In the present study, target-oriented nanoparticles based on biodegradable O-carboxymethyl chitosan modified with stearic acid. The surface of the nanoparticles was modified by covalent attachment of folic acid (FA) by simple carbodimide reaction to achieve tumor cell targeting property. Nanoparticles were prepared by the sonication method without involving any surfactants/emulsifiers. The nanoparticles were characterized by various state-of-the-art techniques, including laser light scattering for particles size distribution, field emission scanning electron microscopy and transmission electron microscope for surface morphology. The drug release property and the cytotoxicity of the drug loaded nanoparticles to both cancerous and noncancerous cells were evaluated in cell culture system. To our knowledge, this is the first study demonstrating a FA modified hydrophobically chitosan with paclitaxel-loaded nanoparticles targeting of folate receptor overexpressing cancer cells.     

壳聚糖包覆的人参皂苷Rg3脂质体的制备及质量评价

目的制备壳聚糖包覆的人参皂苷Rg3脂质体,并进行质量评价。方法采用薄膜分散法、逆相蒸发法、注入法制备脂质体,用壳聚糖包覆;以形态、粒径、包封率为指标筛选制备方法。结果薄膜分散法制备的脂质体外形规则、光滑、平均粒径为10.4μm,包封率为46.96%;壳聚糖包覆后外形圆整,平均粒径为11.1μm,包封率为54.79%。结论采用薄膜分散法制备脂质体并用壳聚糖包覆,质量合格。     

Effect of chitosan malate on viability and cytoskeletal structures morphology of Caco-2 cells

The aim of this work was to evaluate the effects of the treatment with chitosan malate (CM) on viability of Caco-2 cells and on the morphology and the integrity of their cytoskeletal structures (microtubules, microfilaments). Cytotoxicity of CM, both as a solution and as microparticles obtained by spray drying, was evaluated by using the reduction of MTT reagent; microtubule and microfilaments organization of Caco-2 cells treated with CM solution was examined with immunofluorescence techniques in monolayers fixed with the glutaraldehyde-borohydride method.CM as a solution displayed a concentration-dependent cytotoxicity towards Caco-2 cells, with viability percentages of 5 ± 2%, 7 ± 3% and 31 ± 15% at 15, 10 and 5 mg/mL, respectively, while at 2.5 mg/mL or less cell viability was 90% or higher. CM microparticles also produced a remarkable cytotoxic effect (cell viability 84 ± 17%, 16 ± 8% and 5 ± 6% after treatment with 1, 5 and 10 mg CM per well, respectively), resulting more toxic than CM solution.Microtubules pattern of Caco-2 cells, which is a network regularly arranged around the nucleus, appeared deeply modified by CM treatment in a concentration-dependent way, with progressive microtubule changes in length and spatial disposition and deposition of fluorescent aggregates at the periphery of the cells. Furthermore, after treatment with 5-15 mg/mL CM, remarkable alterations of actin organization were observed, with a progressive disruption of the network of stress fibers and the appearance of actin aggregates inside the cell cytoplasm.In conclusion, viability and the cytoskeletal pattern of Caco-2 cells are modified by treatment with CM at high concentrations, which might be locally reached in vivo after application of drug-loaded chitosan microparticles onto mucosal cells.