超小的羧甲基壳聚糖超顺磁氧化铁纳米粒制备及处方优化

目的 优化羧甲壳聚糖超小超顺磁氧化铁纳米粒(O-carboxymethyl-chitosan ultra-small superparamagnetic iron oxide nanoparticle,OCMCS-USPIO-NPs)处方并对其理化性质进行表征。方法 共沉淀法合成超顺磁氧化铁纳米粒核并用羧甲基壳聚糖对其表面进行共价修饰,用正交实验L₉(3^₄)对OCMCS-USPIO-NPs的处方优化和工艺进行优化筛选;用透射电镜、电子相关光谱仪(LSD)、X-Ray衍射法、傅立叶红外、磁性测定仪、MRI扫描仪和邻二氮菲法测定铁含量等对制备的OCMCS-USPIO-NPs进行表征;用普鲁士蓝染色法体外评价OCMCS-USPIO-NPs抗吞噬能力。结果 正交实验处方优化处方为：羧甲基壳聚糖的分子量为1~2万,浓度为3%,超声时间为45 min,功率为600 W;傅立叶红外和X-Rays结果证实了OCMCS-SPIO-NPs的合成,羧甲基壳聚糖的修饰显著降低超顺磁氧化铁的流体粒径及超顺磁性,修饰后饱和磁性为73.4 emu·g^-1 Fe,磁性较强;同时增加纳米粒表面的Zeta电位,普鲁士蓝染色结果表明巨噬细胞吞噬的纳米粒量依次是：uncoated SPIO-NPs＞dextran-SPIO-NPs＞OCMCS-SPIO-NPs。结论 合成的OCMCS-USPIO-NPs的流体粒径<50 nm,具有强的超顺磁性,分散性好,能逃避巨噬细胞的摄取,可用于MRI照影。     

体外评价羧甲基壳聚糖超顺磁氧化铁纳米粒的细胞毒性和巨噬细胞的摄取

目的 体外评价自制羧甲基壳聚糖超顺磁氧化铁纳米粒(OCMCS-SPIO-NPs)的细胞毒性和逃避巨噬细胞的吞噬能力.方法 以菲立磁和未包被的超顺磁氧化铁纳米粒为对照,采用四唑盐(MTT)比色法考察OCMCS-SPIO-NPs对LO2细胞(正常肝细胞株)和A549(人肺腺癌细胞株)的细胞毒性;用菲洛嗪法及普鲁士蓝法考察OCMCS-SPIO-NPs纳米粒并评价其体外的抗吞噬能力.结果 SPIO-NPs经羧甲基壳聚糖共价修饰后,对LO2和A549细胞的细胞毒性明显降低,OCMCS-SPIO-NPs的细胞毒性和dextran-SPIO的细胞毒性无显著性差异(P>0.05),其细胞毒性与培养基中SPIO的浓度呈正相关;与3种SPIO纳米粒孵化24h后,RAW264.7细胞内铁含量随培养基中SPIO的含量增加而增加,细胞内铁含量依次为:未包被SPIO-NPs>dextran-SPIO-NPs>CMCS-SPIO-NPs组(P<0.05).结论 超顺氧化铁纳米粒经羧甲基壳聚糖共价修饰后能显著降低细胞毒性和吞噬细胞摄取,提高了生物相容性,显著降低了巨噬细胞对其的摄取.     

肿瘤靶向超顺磁氧化铁纳米粒的小鼠急性毒性与抗吞噬性评价

目的:考察叶酸-羧甲基壳聚糖-超顺磁氧化铁纳米粒(FA-OCMCS-SPIO-NPs)和羧甲基壳聚糖-超顺磁氧化铁纳米粒(OCMCS-SPIO-NPs)2种造影剂的急性毒性及其抗肝、脾吞噬的能力。方法:尾静脉给予小鼠2种造影剂低、中、高剂量(278、347.5、434.5mg(Fe)·kg-1)后观察14d内的一般情况,计算半数致死量(LD50),并进行各组织病理学检查;以葡聚糖-超顺磁氧化铁纳米粒(dextran-SPIO-NPs)为阳性对照,普鲁士蓝染色法观察2种造影剂经小鼠尾静脉注射相似剂量后抗肝、脾吞噬的能力。结果:2种造影剂的LD50>434.5mg(Fe)·kg-1,所有小鼠均未出现明显的毒性反应和组织病理学改变;普鲁士蓝染色切片结果显示,dextran-SPIO-NPs无法逃避肝、脾中巨噬细胞的吞噬,而FA-OCMCS-SPIO-NPs能完全逃避吞噬,OCMCS-SPIO-NPs大部分逃避了吞噬。结论:2种造影剂的安全性高,且能全身分布,具有潜在的肿瘤靶向载体价值。     

羧甲基壳聚糖超小超顺磁氧化铁纳米粒在大鼠体内的药动学特点及组织分布

摘要 目的：考察羧甲基壳聚糖超小超顺磁氧化铁纳米粒（o-carboxymethyl chitosans ultrasmall superparamagnetic iron oxide nanoparticles, OCMCS-USPIO-NPs）在SD大鼠体内的药物代动力学特征及组织分布,为其临床应用提供依据。方法 SD大鼠分为三大组, 尾静脉注射生理盐水（空白组）、OCMCS-USPIO-NPs（实验组）和葡聚糖超顺磁氧化铁纳米粒(dextran-SPIO-NPs)(阳性对照组)后,原子分光光度法测定血浆和心、肝、脾、肺和肾等组织的铁含量, DAS 药动学软件对血药浓度-时间数据处理,求得OCMCS-USPIO-NPs组和dextran-SPIO-NPs组在大鼠体内的主要药动学参数;绘制组织内铁含量-时间曲线结合普鲁士蓝染色,比较OCMCS-USPIO-NPs和Dextran-SPIO-NPs在大鼠体内组织分布特点。结果：实验组和阳性对照组的主要药动学参数(AUC,MRT,,t1/2,CL,V2,差异显著（P＜0.05),且OCMCS-USPIO-NPs组t1/2大于7小时; 组织分布考察OCMCS-USPIO-NPs组在肝、脾和肺的组织分布浓度显著低于对于对照组。结论：OCMCS-USPIO-NPs能逃避网状内皮系统吞噬,具有长循环作用。     

甲氨蝶呤叶酸受体-磁双重靶向纳米粒的制备及评价

目的：以甲氨蝶呤为药物模型，制备用于肿瘤靶向治疗的叶酸受体-磁双重靶向纳米药物。方法：未采用 预成型的磁性纳米粒，一步合成磁性纳米粒核二氧化硅壳超顺磁性的纳米粒，并借助透射、扫描电镜观察微球形态，用 硅烷偶联剂进行表面修饰，在表面化学偶联上叶酸，修饰甲氨蝶呤后利用紫外可见分光光度计测量载药量及包封率。结 果：磁性纳米粒在电镜下呈现核壳样球型微粒，平均粒径为20 nm，纳米粒载药量为26.71%，包封率为64.76%。结论： 叶酸受体-磁双重载药纳米粒为肿瘤的靶向治疗提供了一种可能的新剂型，有较好的临床应用前景。     

甲氨蝶呤叶酸受体-磁双重靶向纳米粒的制备及评价

目的：以甲氨蝶呤为药物模型，制备用于肿瘤靶向治疗的叶酸受体-磁双重靶向纳米药物。方法：未采用 预成型的磁性纳米粒，一步合成磁性纳米粒核二氧化硅壳超顺磁性的纳米粒，并借助透射、扫描电镜观察微球形态，用 硅烷偶联剂进行表面修饰，在表面化学偶联上叶酸，修饰甲氨蝶呤后利用紫外可见分光光度计测量载药量及包封率。结 果：磁性纳米粒在电镜下呈现核壳样球型微粒，平均粒径为20 nm，纳米粒载药量为26.71%，包封率为64.76%。结论： 叶酸受体-磁双重载药纳米粒为肿瘤的靶向治疗提供了一种可能的新剂型，有较好的临床应用前景。     

甲氨蝶呤叶酸受体-磁双重靶向纳米粒的制备及评价

目的：以甲氨蝶呤为药物模型，制备用于肿瘤靶向治疗的叶酸受体-磁双重靶向纳米药物。方法：未采用 预成型的磁性纳米粒，一步合成磁性纳米粒核二氧化硅壳超顺磁性的纳米粒，并借助透射、扫描电镜观察微球形态，用 硅烷偶联剂进行表面修饰，在表面化学偶联上叶酸，修饰甲氨蝶呤后利用紫外可见分光光度计测量载药量及包封率。结 果：磁性纳米粒在电镜下呈现核壳样球型微粒，平均粒径为20 nm，纳米粒载药量为26.71%，包封率为64.76%。结论： 叶酸受体-磁双重载药纳米粒为肿瘤的靶向治疗提供了一种可能的新剂型，有较好的临床应用前景。     

甲氨蝶呤叶酸受体-磁双重靶向纳米粒的制备及评价

目的：以甲氨蝶呤为药物模型,制备用于肿瘤靶向治疗的叶酸受体-磁双重靶向纳米药物。方法：未采用 预成型的磁性纳米粒,一步合成磁性纳米粒核二氧化硅壳超顺磁性的纳米粒,并借助透射、扫描电镜观察微球形态,用 硅烷偶联剂进行表面修饰,在表面化学偶联上叶酸,修饰甲氨蝶呤后利用紫外可见分光光度计测量载药量及包封率。结 果：磁性纳米粒在电镜下呈现核壳样球型微粒,平均粒径为20 nm,纳米粒载药量为26.71%,包封率为64.76%。结论： 叶酸受体-磁双重载药纳米粒为肿瘤的靶向治疗提供了一种可能的新剂型,有较好的临床应用前景。     

壳聚糖修饰的托氟啶固体脂质纳米粒的制备

摘 要 目的： 研究托氟啶固体脂质纳米粒及壳聚糖修饰的托氟啶固体脂质纳米粒的制备方法。方法: 采用薄膜 超声分散法制备托氟啶固体纳米脂质粒（TFu-SLNs）及壳聚糖修饰的TFu-SLNs,并对纳米粒的形态、粒径和表面电位进行测定,通过单因素考察及正交设计优化制备方法,同时考察处方稳定性。结果: 薄膜 超声分散法制备的TFu-SLNs平均粒径为160.2 nm,Zeta电位为－33.12 mV,壳聚糖修饰TFu-SLNs平均粒径为400.3 nm,Zeta电位为+12.87 mV。经壳聚糖修饰后,随着壳聚糖浓度的增加,电位逐渐增大。优化后的处方重复性、稳定性良好。结论:通过采用正交设计法对TFu固体脂质纳米粒处方进行优化,得到TFu固体脂质纳米粒及壳聚糖修饰的TFu固体脂质纳米粒的优化处方。     

超顺磁性氧化铁纳米粒表面改性及其在生物医学应用研究进展

超顺磁性氧化铁作为近年来发展起来的一种新型超顺磁性造影剂,由于其具有优良的性能,已成为磁共振成像研究热点.本文就超顺磁性氧化铁纳米粒表面改性及其在生物医学领域中的应用做一综述.     

Tumor selectivity of stealth multi-functionalized superparamagnetic iron oxide nanoparticles

Superparamagnetic iron oxide nanoparticles (SPIO-NPs) have traditionally been used as MRI contrast agent for disease imaging via passive targeting. However, there has been an increasing interest in the development of SPIO-NPs to cellular-specific targeting for imaging and drug delivery currently. The objective of our study was to develop a novel active tumor-targeting SPIO-NPs system by surface-modifying superparamagnetic iron oxide nanoparticles (SPIO-NPs) with o-carboxymethyl chitosans (OCMCS) and folic acid (FA) to improve their biocompatibility and ability to target specific tumor cells as well as to evade reticuloendothelial system (RES). The results in vitro indicated the covalent surface-modification of SPIO-NPs with OCMCS significantly reduced not only the nano-cytotoxicity but also the capture of SPIO-NPs by macrophage cells. On the other hand, the folic acid modification promoted the uptake of nanoparticles by FR-positive tumor cell lines, but had little impact on other cells without folate receptor (FR). MRI image and tumor histological analysis demonstrated the FA-OCMCS-SPIO-NPs had the ability to target tumor cells with FR in vivo. OCMCS and folic acid modification of SPIO-NPs could significantly improve both the SPIO-NPs biocompatibility and the FR target for MRI imaging, potential carrier for drug targeting and hyperthermia.     

Suspension of Fe(3)O(4) nanoparticles stabilized by chitosan and o-carboxymethylchitosan

In this study, a well-dispersed suspension of superparamagnetic Fe₃O₄ nanoparticles was stabilized by chitosan (CS) and o-carboxymethylchitosan (OCMCS), respectively. The resulting magnetic Fe₃O₄ nanoparticles were characterized by dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscope (TEM), zeta-potential measurement and vibrating sample magnetometry (VSM). TEM results demonstrated a spherical or ellipsoidal morphology with an average diameter of 14–20 nm. The adsorbed layer of CS and OCMCS on the magnetite surface was confirmed by FTIR. XRD illustrated that the resulting magnetic nanoparticles have a spinel structure and lastly VSM results showed the modified magnetic Fe₃O₄ nanoparticles were superparamagnetic. The adsorption mechanism of CS and OCMCS onto the surface of Fe₃O₄ nanoparticles is believed to be the electrostatic and coordination interactions, respectively. The mechanisms of both CS and OCMCS stabilizing the suspension of Fe₃O₄ nanoparticles were supposed electrostatic repulsion. These well-dispersed superparamagnetic Fe₃O₄ nanoparticles stabilized by the biocompatible CS or OCMCS dispersant should have potential applications in biotechnology fields.     

Endoplasmic reticulum stress mediates inflammatory response triggered by ultra-small superparamagnetic iron oxide nanoparticles in hepatocytes

Abstract

Ultra-small superparamagnetic iron oxide nanoparticles (USPIO-NPs) are widely used as clinical magnetic resonance imaging contrast agents for hepatic diseases diagnosis. USPIO-NPs often damage the hepatocytes and affect the function of liver but its mechanism of action remains unclear. In the present study, USPIO-NPs caused higher cytotoxicity and lactate dehydrogenase (LDH) leakage in hepatic L02 cells than SPIO-NPs. Subsequently, USPIO-NPs affected more genes’ expression than SPIO-NPs analyzed through microarray and bioinformatics analysis. The affected genes were involved in several biological processes, including calcium ion homeostasis, inflammatory response-related leukocyte chemotaxis, and migration. In addition, the level of endoplasmic reticulum (ER) calcium ion was increased by USPIO-NPs. USPIO-NPs also upregulated the genes related to acute-phase inflammation, including IL1B, IL6, IL18, TNFSF12, TNFRSF12, SAA1, SAA2, JAK1, STAT5B, and CXCL14. Furthermore, interleukin-6 (IL-6) secretion was elevated by USPIO-NPs as detected using ELISA. On the other hand, USPIO-NPs changed the morphology of ER and triggered the ER stress and unfolded protein response PERK/ATF4 pathway. Furthermore, blocking ER stress with inhibitor or ATF4 small interfering RNA counteracted IL-6-related acute-phase inflammation and cytotoxicity caused by USPIO-NPs. Taken together, we found that the USPIO-NPs could trigger stronger IL-6-related acute-phase inflammation than SPIO-NPs in hepatocytes. We demonstrated, for the first time, that IL-6-related acute-phase inflammation caused by NPs was regulated by PERK/ATF4 signaling. The PERK/ATF4 pathway explored in this study could be a candidate for diagnostic and therapeutic target against NPs-induced liver injury and cytotoxicity, which would be helpful for USPIO-NPs medical application.     

Temozolomide loaded PLGA-based superparamagnetic nanoparticles for magnetic resonance imaging and treatment of malignant glioma

Polysorbate 80 coated temozolomide-loaded PLGA-based superparamagnetic nanoparticles (P80-TMZ/SPIO-NPs) were successfully synthesized and characterized as drug carriers and diagnosis agent for malignant brain glioma. The mean size of P80-TMZ/SPIO-NPs was 220 nm with narrow hydrodynamic particle size distribution. The superparamagnetic characteristic of P80-TMZ/SPIO-NPs was proved by vibration simple magnetometer. P80-TMZ/SPIO-NPs exhibited high drug loading and encapsulation efficiency as well as good sustained drug release performance for 15 days. MTT assay demonstrated the antiproliferative effect of P80-TMZ/SPIO-NPs for C6 glioma cells. Significant cellular uptake of P80-TMZ/SPIO-NPs was evaluated in C6 glioma cells by fluorescence microscopy, Prussian blue staining, and atomic absorption spectrophotometer (AAS) for qualitative and quantitative study, respectively. MRI scanning analyses in vitro indicated that P80-TMZ/SPIO-NPs could be used as a good MRI contrast agent. Polysorbate 80 coated temozolomide-loaded PLGA-based superparamagnetic nanoparticles could be able to promise a multifunctional theragnostic carrier of brain cancer.     

High-content analysis for mitophagy response to nanoparticles: A potential sensitive biomarker for nanosafety assessment

Mitophagy, a selective autophagy of mitochondria, clears up damaged mitochondria to maintain cell homeostasis. We performed high-content analysis (HCA) to detect the increase of PINK1, an essential protein controlling mitophagy, in hepatic cells treated with several nanoparticles (NPs). PINK1 immunofluorescence-based HCA was more sensitive than assays and detections for cell viability and mitochondrial functions. Of which, superparamagnetic iron oxide (SPIO)-NPs or graphene oxide-quantum dots (GO-QDs) was selected as representatives for positive or negative inducer of mitophagy. SPIO-NPs, but not GO-QDs, activated PINK1-dependent mitophagy as demonstrated by recruitment of PARKIN to mitochondria and degradation of injured mitochondria. SPIO-NPs caused the loss of mitochondrial membrane potential, decrease in ATP, and increase in mitochondrial reactive oxide species and Ca²⁺. Blocking mitophagy with PARKIN siRNA aggravated the cytotoxicity of SPIO-NPs. Taken together, PINK1 immunofluorescence-based HCA is considered to be an early, sensitive, and reliable approach to evaluate the bioimpacts of NPs.     

Mannosylated nanoparticulate carriers of rifabutin for alveolar targeting

The objective of the present study was to evaluate the prospective of engineered nanoparticles for selective delivery of an antituberculosis drug, rifabutin, to alveolar tissues. Drug-loaded solid lipid nanoparticles (SLNs) were synthesized and efficiently mannosylated. The formation of uncoated and coated SLNs was characterized by FTIR spectroscopy and SEM studies. A variety of physicochemical parameters such as drug loading, particle size, polydispersity index, zeta potential, and in vitro drug release were determined. The toxicity and targeting potential of the prepared formulation were assessed with alveolar macrophage uptake, hematological studies, and in vivo studies of uncoated and coated SLNs. Ex vivo cellular uptake studies of SLNs formulations in alveolar macrophages depicted almost six times enhanced uptake due to mannose coating. The hematological studies proved mannose-conjugated system to be less immunogenic and suitable for sustained delivery as evaluated against uncoated formulation. Further, the serum level and organ distribution studies demonstrated efficiency of the system for prolonged circulation and spatial delivery of rifabutin to alveolar tissues. Finally, it was concluded that mannose-conjugated SLNs can be exploited for effective and targeted delivery of rifabutin compared to its uncoated formulation and ultimately increasing the therapeutic margin of safety while reducing the side effects.     

Novel superparamagnetic iron oxide nanoparticles for tumor embolization application: preparation, characterization and double targeting

The goal of this study was to develop novel embolic nanoparticles for targeted tumor therapy with dual targeting: magnetic field-guided and peptide-directed targeting. The embolic nanoparticles SP5.2/tTF-OCMCs-SPIO-NPs were prepared by surface-modifying of superparamagnetic iron oxide nanoparticles (SPIO-NPs) with o-carboxymethylchitosans (OCMCs) and SP5.2/tTF (SP5.2: a peptide binding to VEGFR-1; tTF: truncated tissue factor) to improve their stability and to target over-expressing VEGFR-1 cells. The physicochemical characterization results showed that the OCMCs-SPIO-NPs have a spherical or ellipsoidal morphology with an average diameter of 10-20 nm. And they possess magnetism with a saturation magnetization of 66.1 emu/g, negligible coercivity and remanence at room temperature. In addition, the confocal microscopy, Prussian blue staining and FX activation analysis respectively demonstrated the peptide-directed targeting, magnetic field-guided targeted and blood coagulation activity of the SP5.2/tTF-OCMCs-SPIO-NPs. These properties separately belong to SP5.2, Fe(3)O(4) and tTF moieties of the SP5.2/tTF-OCMCs-SPIO-NPs. Thus these SP5.2/tTF-OCMCs-SPIO-NPs with double-targeting function should have a potential application in embolization therapy of tumor blood vessels.