共载阿霉素和siRNA的还原敏感型前药纳米粒的制备及体外评价

目的：构建共载阿霉素（DOX）和siRNA的还原敏感型前药纳米粒（PSCSD NPs）,并对其理化性质、细胞摄取和体外细胞毒性进行考察。方法：采用核磁共振氢谱（1H NMR）和傅里叶红外光谱（FT-IR）对羧甲基壳聚糖-二硫键-DOX(CMCSS-DOX)进行结构表征;超声法制备PSCSD NPs,考察其粒径、载药量、包封率、血清稳定性、溶血率和体外释药特性等;采用荧光显微镜和流式细胞术考察4T1细胞对PSCSD NPs的摄取;通过MTT实验测定PSCSD NPs的体外细胞毒性。结果：1H NMR和FT-IR结果表明CMC-SS-DOX成功合成;PSCSD NPs的粒径为（155.1±4.0） nm(PDI=0.144±0.028),Zeta电位为（–29.9±1.0） mV,载药量为（8.25±0.47）%,包封率为（78.41±4.52）%;透射电镜观察PSCSD NPs为球形,且具有良好的血液相容性和血清稳定性。PSCSD NPs具有还原响应释药特性,可在肿瘤部位快速释药。细胞摄取和MTT实验结果表明PSCSD NPs可以有效共载DOX和siRNA进入肿瘤细胞内以发挥抗肿瘤作用。...     

阿霉素修饰纳米银的制备及其体外抗肿瘤活性研究

摘要： 目的 设计合成一类新型的具有pH响应性的阿霉素-纳米银 （DOX-Ag NPs） 联合抗肿瘤药物, 对其理化性质进行表征, 并研究其体外响应性释药行为和抗肿瘤活性。方法 通过硫辛酰肼 （LA-NHNH2 ） 连接纳米银 （Ag NPs） 和阿霉素 （DOX）, 得到DOX-Ag NPs。利用核磁氢谱 （1 H NMR） 和高分辨质谱 （HRMS） 对硫辛酰肼-阿霉素 （LA- NHN=DOX） 进行结构确证; 通过动态光散射 （DLS） 和透射电镜 （TEM） 分析纳米粒的粒径和形貌; 通过紫外-可见吸收光谱和荧光光谱表征纳米粒的光学性质; 通过透析法结合荧光光谱检测DOX-Ag NPs在不同pH下的DOX释放行为; 采用噻唑蓝比色法研究DOX-Ag NPs对HepG2肿瘤细胞的增殖抑制效果。结果 LA-NHN=DOX的1 H NMR数据及HRMS检测到746.275 6处的分子离子峰均证明LA-NHN=DOX成功合成。DOX-Ag NPs为粒径 （40.4±3.8） nm的球形纳米粒; 在弱酸性条件下DOX-Ag NPs能够快速响应性释放DOX; DOX-Ag NPs对HepG2肿瘤细胞增殖抑制呈现浓度依赖性, 当DOX浓度为0.5~20 mg/L （Ag浓度为0.45~18 mg/L） 时, DOX-Ag NPs组细胞生存率均明显低于DOX 组和Ag NPs组 （均P＜0.05）。结论 DOX-Ag NPs是一种具有pH响应性的联合抗肿瘤纳米制剂, 能在肿瘤组织快速释放DOX, 并通过与Ag NPs的协同治疗, 发挥良好的体外抗肿瘤作用。     

双重响应靶向双药协同递送纳米系统的制备及体外评价

目的:制备双重响应靶向性双载药纳米粒(DOX/CMCS-ss-MTX NPs),并进行体外抗肿瘤考察。方法:甲氨蝶呤(MTX)通过二硫键接枝到羧甲基壳聚糖(CMCS)上,核磁共振氢谱(¹H-NMR)、红外光谱(IR)确证结构。离子交联法制备纳米粒,对粒径、Zeta电位进行表征;测定载阿霉素(DOX)和甲氨蝶呤(MTX)的DOX/CMCS-ss-MTX NPs包封率和载药量;MTT实验考察DOX/CMCS-ss-MTX NPs体外抗肿瘤活性。结果:DOX/CMCS-ss-MTX NPs粒径为(148.3±2.5)nm,阿霉素载药量为(17.10±0.28)%,包封率为(71.32±3.54)%;甲氨蝶呤载药量为(19.35±0.33)%,包封率为(86.9±2.35)%。实验证明其具有pH和还原响应,肿瘤微环境下可快速释放。MTT实验表明DOX/CMCS-ss-MTX NPs对正常肝细胞没有明显影响,对肝癌细胞有明显抑制作用。结论:DOX/CMCS-ss-MTX NPs粒径均一、载药量较高,具有良好的pH响应性和还原响应性,共同递送甲氨蝶呤和阿霉素,具有协同抗肿瘤效...     

阿霉素壳寡糖纳米粒的制备及体外抗肿瘤研究

目的制备负载阿霉素的壳寡糖纳米粒,并研究其理化性质和体外抗肿瘤细胞毒性。方法采用离子凝胶法制备负载阿霉素的壳寡糖纳米粒;透射电镜观察纳米粒形态,激光粒度仪测定粒径和表面电位,紫外分光光度法测量包封率、载药量,考察载药纳米粒的体外释药特性;采用MTT法对载药壳寡糖纳米粒在体外乳腺癌细胞株MCF-7的细胞毒作用进行评价。结果制得的阿霉素壳寡糖纳米粒呈球形或类球形,形态较为完整,平均粒径为(136.77±1.21)nm,表面电位为(20.53±0.31)m V,包封率为(56.99±1.40)%,载药量为(15.49±0.38)%,168 h的累积释放率为72.15%;阿霉素和载药纳米粒对MCF-7细胞增殖的抑制作用存在明显的浓度和时间依赖性,且载药纳米粒对MCF-7细胞增殖的抑制作用随时间增加而逐渐强于游离阿霉素。结论此方法制备的阿霉素壳寡糖纳米粒粒径较小,药物释放具有明显的缓释作用,并具有较好的抗肿瘤作用。     

酸敏感阿霉素前药纳米粒的合成及其在治疗脑胶质瘤中的作用

摘要： 目的 合成一类新的具有酸敏感性能的阿霉素前药纳米粒 （PEG-DOX NPs）, 对其结构进行表征, 并研究其在体外抗脑胶质瘤中的作用和透过血脑屏障的效率。方法 通过席夫碱反应合成具有酸敏感的聚乙二醇-阿霉素 （PEG-DOX） 单体, 通过自组装制备 PEG-DOX NPs。利用动态光散射 （DLS） 和核磁对单体进行结构表征, 通过透射电镜 （TEM） 对纳米粒的微观形貌进行观察, 紫外检测法测定 PEG-DOX NPs 在酸性条件下的释放行为, 荧光显微镜观察脑胶质瘤细胞对 PEG-DOX NPs 的摄取行为。利用MTT 法测定 PEG-DOX NPs 与阿霉素 （DOX） 对脑胶质瘤细胞的杀伤作用。PEG-DOX NPs 修饰吐温 80 （PS-80） 获得 PS80-PEG-DOX NPs。将 9 只 BALB/c 小鼠随机均分为 Free DOX 组、 PEG-DOX NPs 组和 PS80-PEG-DOX NPs 组, 利用小动物活体成像系统比较其修饰前后脑及主要脏器内 DOX 的荧光强度。结果 PEG-DOX 能够自组装成直径 100 nm 左右的纳米粒; 在酸性条件下 PEG-DOX NPs 能够快速释放 DOX, 肿瘤细胞对 PEG-DOX NPs 的摄取虽然比 DOX 慢, 但蓄积时间更长; PEG-DOX NPs 和 Free DOX 对 C6 细胞的增殖抑制均呈现浓度依赖性, PEG-DOX NPs 组细胞增殖抑制率在各个浓度下均低于 Free DOX 组。 PS-80 修饰后, PS80-PEG-DOX NPs 透过血脑屏障的效率显著高于 DOX 和 PEG-DOX NPs 组。结论 PEG-DOX NPs 具有良好的体外抗肿瘤作用, 修饰后可高效透过血脑屏障, 使其体内治疗脑胶质瘤成为可能。     

壳寡糖-水杨酸接枝物纳米粒用于释放阿霉素的研究

目的 考察壳寡糖/水杨酸纳米粒负载碱化阿霉素的可能性,评价制备而得的微粒给药系统理化性质及其体外释放行为。方法 以碳二亚胺为交联偶合剂合成壳寡糖/水杨酸接枝共聚物,三硝基苯磺酸法测定水杨酸接枝率。运用超声分散法制备壳寡糖/水杨酸空白纳米粒,芘荧光法测定纳米粒临界聚集浓度,动态光散射法测定微粒粒径和表面电位,MTT法考察空白纳米粒的细胞毒性。以碱化阿霉素为模型药物,透析法制备壳寡糖/水杨酸载药纳米粒,经透射电镜考察载药纳米粒的形态,对其体外释放行为进行了研究。结果 合成得到的壳寡糖分子量=9000/水杨酸理论投料量=50%的实际接枝率为16.92%,空白纳米粒的临界聚集浓度为867.0 μg/mL,空白纳米粒的粒径和表面Zeta电位分别为434.0 nm和48.6 mV,对人肝癌细胞Hep-G2的半数抑制浓度为1745μg/mL。在碱化阿霉素理论投药量为10%时壳寡糖/水杨酸载药纳米粒的实际载药量为8.52%,包封率为93.15%。;载药纳米粒的粒径和表面电位分别为214.2 nm和33.6 mV。体外释放结果表明药物的释放呈现pH敏感性;并主要以溶蚀的方式从载体内部释放出来。结论 壳寡糖/水杨酸接枝物可以有效包裹碱化阿霉素并成为粒径均一的纳米粒给药系统。载药纳米粒具有pH敏感和缓释作用。壳寡糖/水杨酸接枝物有望成为潜在的难溶性药物的载体材料。     

PLGA-TPGS 负载α-TIF-siRNA 纳米粒对疱疹病毒1的抑制作用

目的：研究以 PLGA-TPGS 生物可降解材料为载体包载α-TIF-siRNA 的纳米粒对 HSV1的抑制作用。方法以 PLGA-TPGS 为载体,采用双乳蒸发法制备包载α-TIF-siRNA 的 PLGA-TPGS 纳米粒（命名为 PLGA-TPGS/α-TIF-siRNA NPs）,并对其进行表征,包括粒径大小、zeta 电位、包封率和释放率,用 MTT 法检测纳米粒对上皮细胞和HeLa 细胞的细胞毒作用,免疫荧光观察纳米粒在细胞内的释放,用空斑实验研究体外研究纳米粒对 HSV1病毒的抑制作用。结果 PLGA-TPGS/α-TIF-siRNA NPs 的粒径大小为（257±2.94）nm,zeta 电位为（-31.25±1.70）mV,siRNA的包封率为（56.23±3.68）％,纳米释放 siRNA 呈双相,即在96 h 释放达到50％,之后呈缓慢释放,用 MTT 法分析 PL-GA-TPGS/α-TIF-siRNA NPs 对原代角质形成细胞和 HeLa 细胞几乎无细胞毒性。荧光显微镜能观察纳米粒 siRNA 细胞内释放。PLGA-TPGS/α-TIF-siRNA NPs 能明显延长抑制感染 HeLa 细胞的 HSV1。结论 PLGA-TPGS 纳米粒可以作 siRNA 的载体。PLGA-TPGS/α-TIF-siRNA NPs 在体外对 HSV1病毒具有明显的抑制作用,可以成为治疗 HSV1-诱导的角膜炎在内的相关疾病的候选药物。     

载阿霉素透明质酸聚合物纳米粒的构建及其体外性质研究

目的 合成透明质酸（HA）接枝单油酸甘油酯（GMO）两亲性聚合物HGO,并研究其所制备载阿霉素（DOX）纳米粒的理化性质及体外抗肿瘤效果。方法 HA与GMO通过酯化反应制得载体聚合物HGO,通过核磁共振波谱法及红外光谱法对其进行结构表征;采用芘荧光探针法测定聚合物临界聚集浓度（CAC）。采用透析法制备聚合物HGO载阿霉素（DOX@HGO）纳米粒,并对其进行粒径分布、Zeta电位及微观形态的表征;通过检测其在不同离子强度、不同pH条件下的粒径变化考察纳米粒的体外稳定性;考察DOX@HGO纳米粒在不同pH条件下的体外释放行为;CCK-8法考察DOX@HGO纳米粒对MDA-MB-231细胞的体外抑瘤效果;并通过荧光显微镜研究MDA-MB-231细胞对DOX溶液、DOX@HGO纳米粒的摄取能力,以及HA预处理对DOX@HGO纳米粒摄取的影响。结果 成功制得两亲性聚合物HGO,聚合物HGO中GMO的取代度为15.8%,CAC为0.023 mg·mL^-1。DOX@HGO纳米粒呈规则的球形,平均粒径为（130.800±1.709）nm,平均电位为（-32.600±0.153）mV,包封率和载药量分别为（98.65±0.74）%和（33.03±0.17）%,在不同离子强度下、模拟胃肠液中表现出良好的稳定性;DOX@HGO纳米粒的体外释放表现出pH依赖性。体外抗肿瘤活性实验表明,DOX@HGO纳米粒对MDA-MB-231细胞的生长具有较好的抑制作用;与DOX溶液比较,DOX@HGO纳米粒显著增加肿瘤细胞对于DOX的摄取（P＜0.05） ,HA预处理显著减少肿瘤细胞对DOX@HGO的摄取（P＜0.05）。结论 所构建的DOX@HGO纳米粒具有良好的理化性质,并且具有一定的pH敏感性及靶向抗肿瘤细胞的能力,是具有应用潜力的药物载体。     

还原响应型靶向自载药纳米粒的制备及其体外评价

目的 制备靶向性的自载药纳米粒(HA-ss-Bai NPs),并考察其作为药物载体递送姜黄素(curcumin,Cur)的可行性。方法 制备二硫键连接的透明质酸(hyaluronic acid,HA)-黄芩苷(baicalin,Bai)聚合物,利用核磁共振氢谱(hydrogen nuclear magnetic resonance spectroscopy,¹H-NMR)、红外光谱(infrared spectroscopy,IR)确证聚合物的结构;采用超声法制备自组装纳米粒,并对其粒径、Zeta电位进行表征;采用芘荧光探针法测定纳米粒的临界聚集浓度(criticalaggregation concentration,CAC);测定载Cur纳米粒包封率和载药量;MTT试验考察载药纳米粒的体外抗肿瘤活性。结果 制备HA-ss-BaiNPs,最小粒径为(124.3±6.5)nm,CAC值为(0.023 8±0.003 5)mg·mL^–1。测得Cur/HA-ss-BaiNPs的粒径为(172.5±3.2)nm,载药量为(17.08±0.25)%,包...     

载多柔比星二氧化钛纳米粒的制备及体外评价

目的制备载多柔比星（doxorubicin,DOX）的二氧化钛（Ti02）纳米粒,并考察其体外释放百分率及细胞毒性。方法通过水热法合成DOX的Ti02纳米粒,采用透射电镜及X-射线衍射仪对其进行表征,紫外可见分光光度法测定载药量及体外释放,采用MTT法分析其对MCF-7细胞和Hela细胞的细胞毒性。结果所制备的纳米粒分散均匀。外观呈梭状,长度约为200nm,在水中的载药量达10．85％,体外释放具有pH敏感性,空白纳米粒细胞毒性较低,载药纳米粒的细胞毒性与游离多柔比星相当。结论所制备的TiO2纳米粒具有较高的载药量及pH敏感的体外释放性能,可作为DOX的载体。     

聚水杨酸氧化还原响应型纳米载药系统的制备及体外评价

目的 将聚水杨酸(poly-salicylic acid,PSA)连接到羧甲基壳聚糖上,使其形成自组装纳米粒(nanoparticles,NPs),并进行表征和体外评价。方法 以O-羧甲基壳聚糖(O-carboxymethyl chitosan,OCMC)作为亲水骨链,通过二硫键将PSA连接在羧甲基壳聚糖上。利用核磁共振氢谱(¹H-NMR)、红外光谱(IR)确证聚合物的结构;采用超声法制备自组装NPs,并对其粒径、Zeta电位进行表征;采用芘荧光探针法测定NPs的临界聚集浓度(critical aggregation concentration,CAC);测定载DOX NPs包封率和载药量;MTT试验考察载药NPs的体外抗肿瘤活性。结果 OCMC二硫键连接PSA NPs(OCMC-SS-PSA NPs)的粒径为(148.5±2.3)nm;CAC值为(0.069 3±0.001 3)mg·mL^-1;还原响应性和pH敏感性良好。DOX/OCMC-SS-PSA NPs的粒径为(160.5±1.7)nm,载药量为(17.43±0.56)%,包封率为(89.67±1.23)%。MTT试验表明OCMC-SS-PSA NPs具有良好的生物安全性;细胞摄取试验表明DOX/OCMC-SS-PSA NPs在细胞内滞留时间更长。结论 OCMC-SS-PSA NPs粒径较小,具有良好的还原响应性、pH敏感性和生物安全性。OCMC-SS-PSA NPs可作为兼具还原响应性和pH敏感性的纳米给药系统。     

Cytotoxicity and apoptotic gene expression in an in vitro model of the blood–brain barrier following exposure to poly(butylcyanoacrylate) nanoparticles

Background Poly(butylcyanoacrylate) (PBCA) nanoparticles (NPs) loaded with doxorubicin (DOX) and coated with polysorbate 80 (PS80) have shown efficacy in the treatment of rat glioblastoma. However, cytotoxicity of this treatment remains unclear.

Purpose The purpose of this study was to investigate cytotoxicity and apoptotic gene expression using a proven in vitro co-culture model of the blood–brain barrier.

Methods The co-cultures were exposed to uncoated PBCA NPs, PBCA-PS80 NPs or PBCA-PS80-DOX NPs at varying concentrations and evaluated using a resazurin-based cytotoxicity assay and an 84-gene apoptosis RT-PCR array.

Results The cytotoxicity assays showed PBCA-PS80-DOX NPs exhibited a decrease in metabolic function at lower concentrations than uncoated PBCA NPs and PBCA-PS80 NPs. The apoptosis arrays showed differential expression of 18 genes in PBCA-PS80-DOX treated cells compared to the untreated control.

Discussion As expected, the cytotoxicity assays demonstrated enhanced dose-dependent toxicity in the DOX loaded NPs. The differentially expressed apoptotic genes participate in both the tumor necrosis factor receptor-1 and mitochondria-associated apoptotic pathways implicated in current DOX chemotherapeutic toxicity.

Conclusion The following data suggest that the cytotoxic effect may be attributed to DOX and not the NPs themselves, further supporting the use of PBCA-PS80 NPs as an effective drug delivery vehicle for treating central nervous system conditions.     

载姜黄素的透明质酸-熊果酸-硫辛酸交联纳米粒的制备及其体外抗肿瘤活性

目的 制备载姜黄素的透明质酸-熊果酸-硫辛酸交联纳米粒（Cur/cLA-HU NPs）,并进行体外抗肿瘤活性评价。方法 以载药量、包封率为指标,采用超声法,通过单因素考察优化Cur/cLA-HU NPs的制备工艺,并对Cur/cLA-HU NPs的粒径、Zeta电位、形态和体外释药情况进行评价。通过荧光倒置显微镜分析HepG2细胞对Cur/cLA-HU NPs的摄取,以MTT法考察Cur/cLA-HU NPs对HepG2细胞的毒性。结果 最佳载药工艺为：以甲醇为药物姜黄素有机溶剂,以药质比4∶10进行投料,超声于100 W下次数为3次,每次处理3 min,超声程序设置为开2 s、停4 s。Cur/cLA-HU NPs的包封率为（87.91±1.51）%,载药量为（16.64±0.45）%,粒径为（172.3±2.57）nm,PDI为（0.174±0.021）,分散均匀,Zeta电位为（−35.3±2.12）mV。Cur/cLA-HU NPs具有还原响应性,释放药物的快慢受到GSH浓度的影响;靶向肿瘤细胞,且被细胞快速摄取;对HepG2人肝癌细胞增殖具有明显抑制作用。结论 Cur/cLA-HU NPs载药量和包封率高,其体外抗肿瘤活性稍优于姜黄素,具有肿瘤靶向性。     

Self-assembled nanoparticles of reduction-sensitive poly (lactic-co-glycolic acid)-conjugated chondroitin sulfate A for doxorubicin delivery: preparation,characterization and evaluation

In this study, reduction-sensitive self-assembled polymer nanoparticles based on poly (lactic-co-glycolic acid) (PLGA) and chondroitin sulfate A (CSA) were developed and characterized. PLGA was conjugated with CSA via a disulfide linkage (PLGA-ss-CSA). The critical micelle concentration (CMC) of PLGA-ss-CSA conjugate is 3.5?µg/mL. The anticancer drug doxorubicin (DOX) was chosen as a model drug, and was effectively encapsulated into the nanoparticles (PLGA-ss-CSA/DOX) with high loading efficiency of 15.1%. The cumulative release of DOX from reduction-sensitive nanoparticles was only 34.8% over 96?h in phosphate buffered saline (PBS, pH 7.4). However, in the presence of 20?mM glutathione-containing PBS environment, DOX release was notably accelerated and almost complete from the reduction-sensitive nanoparticles up to 96?h. Moreover, efficient intracellular DOX release of PLGA-ss-CSA/DOX nanoparticles was confirmed by CLSM assay in A549 cells. In vitro cytotoxicity study showed that the half inhibitory concentrations of PLGA-ss-CSA/DOX nanoparticles and free DOX against A549 cells were 1.141 and 1.825?µg/mL, respectively. Therefore, PLGA-ss-CSA/DOX nanoparticles enhanced the cytotoxicity of DOX in vitro. These results suggested that PLGA-ss-CSA nanoparticles could be a promising carrier for drug delivery.     

Brain-targeted delivery of doxorubicin using glutathione-coated nanoparticles for brain cancers

Abstract

Objectives: To prepare and characterize in vitro a novel brain-targeted delivery of doxorubicin using glutathione-coated nanoparticles (NPs) for the treatment of brain cancer.

Methods: Doxorubicin-loaded NPs were prepared by the nanoprecipitation method using PLGA-COOH (dl-lactide-co-glycolide). The NPs were coated with a glutathione-PEG conjugate (PEG-GSH) in order to target delivery to the brain. The NPs were characterized via in vitro studies to determine particle size, drug release, cellular uptake, immunofluorescence study, cytotoxic assay, and in vitro blood–brain barrier (BBB) assay.

Results: The NPs showed a particle size suitable for BBB permeation (particle size around 200?nm). The in vitro release profile of the NPs exhibited no initial burst release and showed sustained drug release for up to 96?h. The immunofluorescence study showed the glutathione coating does not interfere with the drug release. Furthermore, in vitro BBB Transwell? study showed significantly higher permeation of the doxorubicin-loaded NPs compared with the free doxorubicin solution through the coculture of rat brain endothelial (RBE4) and C6 astrocytoma cells (p?<?0.05).

Conclusions: We conclude that the initial in vitro characterization of the NPs demonstrates potential in delivering doxorubicin to cancer cells with possible future application in targeting brain cancers in vivo.     

Intracellular trafficking of nuclear localization signal conjugated nanoparticles for cancer therapy

Doxorubicin (DOX) is an anticancer drug with an intracellular site of action in the nucleus. For high antitumour activity, it should be effectively internalized into the cancer cells and accumulate in the nucleus. In this study, we have prepared a nuclear localization signal conjugated doxorubicin loaded Poly (d,l-lactide-co-glycolide) nanoparticles (NPs), to deliver doxorubicin to the nucleus efficiently. Physico-chemical characterization of these NPs showed that the drug is molecularly dispersed in spherical and smooth surfaced nanoparticles. NPs (～226 nm in diameter, 46% encapsulation efficiency) under in vitro conditions exhibited sustained release of the encapsulated drug (63% release in 60 days). Cell cytotoxicity results showed that NLS conjugated NPs exhibited comparatively lower IC₅₀ value (2.3 μM/ml) than drug in solution (17.6 μM/ml) and unconjugated NPs (7.9 μM/ml) in breast cancer cell line MCF-7 as studied by MTT assay. Cellular uptake studies by confocal laser scanning microscopy (CLSM) and fluorescence spectrophotometer showed that greater amount of drug is targeted to the nucleus with NLS conjugated NPs as compared to drug in solution or unconjugated NPs. Flow cytometry experiments results showed that NLS conjugated NPs are showing greater cell cycle (G2/M phase) blocking and apoptosis than native DOX and unconjugated NPs. In conclusion, these results suggested that NLS conjugated doxorubicin loaded NPs could be potentially useful as novel drug delivery system for breast cancer therapy.     

Folate-decorated poly(3-hydroxybutyrate-co-3-hydroxyoctanoate) nanoparticles for targeting delivery: optimization and in vivo antitumor activity

Abstract

Context: Doxorubicin (DOX)-loaded folate-targeted poly(3-hydroxybutyrate-co-3-hydroxyoctanoate) [P(HB-HO)] nanoparticles [DOX/FA-PEG-P(HB-HO) NPs] have potential application in clinical treatments for cervical cancer due to specific affinity of folate and folate receptor in HeLa cells.

Objective: The aim of this study was to develop an optimized formulation for DOX/FA-PEG-P(HB-HO) NPs, and investigate the targeting and efficacies of the nanoparticles.

Materials and methods: DOX/FA-PEG-P(HB-HO) NPs were prepared by W₁/O/W₂ solvent extraction/evaporation method, and an orthogonal experimental design [L₉ (3⁴)] was applied to establish the optimum conditions. The physico–chemical characteristics, microscopic observation and in vivo antitumor study of the nanoparticles were evaluated.

Results: The optimum formulation was obtained with DOX 10% (w/v), FA-PEG-P(HB-HO) 6.5% (w/v), PVA 3%(w/v) and oil phase/internal water phase volume ratio of 3/1. The size distribution, drug loading and encapsulation efficiency of the optimized nanoparticles were 150–350?nm, 29.6?±?2.9% and 83.5?±?5.7%, respectively. In vitro release study demonstrated that 80% of the drug could release from the nanoparticles within 11 days. Furthermore, in vitro microscopic observation and in vivo antitumor study showed that DOX/FA-PEG-P(HB-HO) NPs could inhibit HeLa cells effectively, and the tumor inhibition rate (TIR) in vivo was 76.91%.

Discussion and conclusions: DOX/FA-PEG-P(HB-HO) NPs have been successfully developed and optimized. In vitro drug release study suggested a sustained release profile. Moreover, DOX/FA-PEG-P(HB-HO) NPs could effectively inhibit HeLa cells with satisfying targeting, and reduce side effects and toxicity to normal tissues. DOX/FA-PEG-P(HB-HO) NPs were superior in terms of inhibiting HeLa tumor over non-targeted formulations therapy.     

In vitro Evaluation of Doxorubicin‐Incorporated Magnetic Albumin Nanospheres

Magnetic albumin nanospheres that incorporate doxorubicin (M‐DOX‐BSA‐NPs) were prepared previously by our research group to develop magnetically responsive drug carrier system. This nanocarrier was synthesized as a drug delivery system for targeted chemotherapy. In this work, cytotoxic effects of doxorubicin (DOX)‐loaded/unloaded or magnetic/non‐magnetic nanoparticles and free DOX against PC‐3 cells and A549 cells were determined with the MTT test and the results were compared with each other. DOX‐loaded magnetic albumin nanospheres (M‐DOX‐BSA‐NPs) were found more cytotoxic than other formulations. The quantitative data obtained from flow cytometry analysis further verified the higher targeting and killing ability of M‐DOX‐BSA‐NPs than free DOX on both of the cancer cell lines. Additionally, the results of cell cycle analysis have showed that M‐DOX‐BSA‐NPs affected G1 and G2 phases. Finally, cell images were obtained using spin‐disk confocal microscopy, and cellular uptake of M‐DOX‐BSA‐NPs was visualized. The findings of this study suggest that M‐DOX‐BSA‐NPs represent a potential doxorubicin delivery system for targeted drug transport into prostate and lung cancer cells.     

Breast cancer targeted chemotherapy based on doxorubicin-loaded bombesin peptide modified nanocarriers

Context: Breast cancer is the most common cancer in female population. Breast cancer chemotherapy using doxorubicin (DOX) is well illustrated. However, a significant obstacle for successful chemotherapy with DOX is multidrug resistant (MDR) in breast cancer cells. Targeted nanocarriers have emerged as frontier research for the improvement of cancer chemotherapy.

Objective: Bombesin (Bn)-modified, DOX-loaded solid lipid nanoparticles (Bn-DOX/SLNs) were constructed. Doxorubicin-resistant MCF-7/MDR human breast cancer cells and the cancer animal models were applied for the evaluation of the in vitro and in vivo anti-tumor effect of Bn-DOX/SLNs.

Methods: Bn-conjugated lipids were synthesized. DOX was then loaded into Bn-modified SLNs. The physicochemical properties of the Bn-DOX/SLNs were investigated by particle size and zeta potential measurement, drug loading and drug-entrapment efficiency, and in vitro drug release behavior. In vitro cytotoxicity against MCF-7/MDR cells was investigated, and in vivo anti-tumor of SLNs was evaluated in human breast cancer mice models.

Results: Bn-DOX/SLNs showed an excellent in vitro cytotoxicity and in vivo anti-tumor effect both in MCF-7/MDR breast cancer cells and breast cancer animal model.

Conclusion: The results demonstrated that Bn-DOX/SLNs reversed the resistance of doxorubicin, suggesting that chemotherapy using this kind of targeted nanocarriers may benefit human breast MDR cancer therapy.