A polyphosphoester-conjugated camptothecin prodrug with disulfide linkage for potent reduction-triggered drug delivery
作者:Qingqing Zhang、Jinlin He、Mingzu Zhang、Peihong Ni
DOI:10.1039/c5tb00623f
日期:——
of a biodegradable diblock polyphosphoester (PBYP-b-PEEP), and a modified CPT is linked onto the pendant alkynes of PBYP via Cu(i)-catalyzed azide-alkyne cycloaddition (CuAAC) "click" reaction to yield the polymeric prodrug, abbreviated as (PBYP-g-ss-CPT)-b-PEEP. The resulting prodrug could self-assemble into uniform prodrug micelles in aqueous solution. Since the releasable disulfide carbonate between
已开发出一种新型的可还原裂解的喜树碱(CPT)前药,其中聚合物主链由可生物降解的二嵌段聚磷酸酯(PBYP-b-PEEP)组成,并且经过修饰的CPT通过以下方式连接到PBYP的侧链炔烃上Cu(i)催化的叠氮化物-炔烃环加成(CuAAC)“点击”反应可生成聚合物前药,缩写为(PBYP-g-ss-CPT)-b-PEEP。所得的前药可以在水溶液中自组装成均匀的前药胶束。由于CPT和聚磷酸酯之间的可释放的二硫化碳在细胞内还原环境下会被破坏,因此前药胶束的解离可能导致CPT母体药物的快速释放。中间聚合物和聚合物前药的化学结构已通过1 H NMR和FT-IR分析得到了充分表征,而分子量和分子量分布则通过凝胶渗透色谱法(GPC)进行了测量。通过荧光探针法,动态光散射(DLS)和透射电子显微镜(TEM)分析研究了前药的自组装行为。DLS结果表明,这些前药胶束在中性pH介质中相对稳定,但在还原条件下可能被降解
Sheddable, degradable, cationic micelles enabling drug and gene delivery
作者:Yongyong Li、Xue Lei、Haiqing Dong、Tianbin Ren
DOI:10.1039/c3ra46756b
日期:——
In this work, sheddable, degradable, cationic micelles were designed and developed based on intermediate disulfide-linked poly(ε-caprolactone)-b-poly(N,N-dimethylamino-2-ethylmethacrylate) (PCL-SS-PDMA) diblock copolymers, for glutathione (GSH)-mediated intracellular delivery of anticancer drug doxorubicin (DOX) and gene. The PCL-SS-PDMA diblock polymers with different PDMA block lengths were prepared by a combination of ring opening polymerization (ROP) and atom transfer radical polymerization (ATRP). Driven by hydrophobic interaction, these polymers self-assembled into nanoscaled micelles with size ranging from 70 to 200 nm, and positive surface charges from +24 to +37 mV. The PDMA length was found to determine the surface charge and in turn affect the physiochemical properties and cumulative drug release. More importantly, glutathione mediated intracellular drug release was observed by intracellular fluorescence arising from DOX for the GSH treated cells. The accelerated drug release was induced by the structural disassembly after disulfide cleavage. The PCL-SS-PDMA block polymers exhibited high DNA binding affinity and cellular uptake efficiency. The gene transfection efficiency of PCL-SS-PDMA/DNA complex showed relatively low transfection efficiency in 293 T and HeLa cells, compared to PEI 25K. However, the transfection efficacy dramatically outperformed PEI 25K in human oral carcinoma cell lines (KB and CAL-27 cells). A ten-fold population of the transfected cells was found for the PS-SS-PDMA polymer, compared with PEI. The experimental results show the great potential of the new micelles in gene and drug delivery for cancer therapy.
Temperature- and redox-responsive magnetic complex micelles for controlled drug release
作者:Hui Zou、Weizhong Yuan
DOI:10.1039/c4tb01518e
日期:——
PCL-SS-PDMAEMA/Fe3O4 magnetic complex micelles can present dual temperature- and redox-responses, magnetism and magnetothermal properties.
PCL-SS-PDMAEMA/Fe3O4磁性复合微胶束具有双重温度和氧化还原响应、磁性和磁热性能。
Exploring Self-Condensing Vinyl Polymerization of Inimers in Microemulsion To Regulate the Structures of Hyperbranched Polymers
作者:Robert W. Graff、Xiaofeng Wang、Haifeng Gao
DOI:10.1021/acs.macromol.5b00278
日期:2015.4.14
fast polymerization rate with quantitative conversion of methacrylate groups within 0.5 h. At high conversion, there was essentially one hyperbranched polymer per discrete latex particle, whose dimension (hydrodynamic diameter Dh = 10.95–20.13 nm in water) and uniformity directly determined the molecular weight and polydispersity of the hyperbranched polymer. The DB of hyperbranched polymers was quantitatively
已成功开发出一种合成方法,该方法利用微乳液中的受限胶束空间来调节分子的原子转移自由基聚合(ATRP),从而生产出结构明确的超支化聚合物。对实验变量的系统探索,包括基于甲基丙烯酸酯的五个种类的惰性分子,两个ATRP配体以及不同数量的惰性分子和催化剂,产生了一系列涵盖了广泛分子量的超支化聚合物(M n = 194–1301 kg / mol ),高支化度(DB = 0.26-0.41)和窄分子量分布(M w / M n= 1.1–1.7)。微乳液介质中引发剂的ATRP表现出快速的聚合速率,并在0.5小时内实现了甲基丙烯酸酯基团的定量转化。在高转化率下,每个离散的乳胶颗粒基本上都存在一种超支化聚合物,其尺寸(在水中的流体动力学直径D h = 10.95–20.13 nm)和均匀性直接决定了超支化聚合物的分子量和多分散性。超支化聚合物的DB使用反门控13定量测定13 C NMR光谱法,其值受几个参
Folic Acid and Trastuzumab Functionalized Redox Responsive Polymersomes for Intracellular Doxorubicin Delivery in Breast Cancer
作者:Shantanu V. Lale、Arun Kumar、Shyam Prasad、Alok C. Bharti、Veena Koul
DOI:10.1021/acs.biomac.5b00244
日期:2015.6.8
Redox responsive biodegradable polymersomes comprising of poly(ethylene glycol)-polylactic acid-poly(ethylene glycol) [PEG-s-s-PLA-s-s-PLA-s-s-PEG] triblock copolymer with multiple disulfide linkages were developed to improve intracellular delivery and to enhance chemotherapeutic efficacy of doxorubicin in breast cancer with minimal cardiotoxicity. Folic acid and trastuzumab functionalized monodispersed polymersomes of size ∼150 nm were prepared by nanoprecipitation method while achieving enhanced doxorubicin loading of ∼32% in the polymersomes. Multiple redox responsive disulfide linkages were incorporated in the polymer in order to achieve complete disintegration of polymersomes in redox rich environment of cancer cells resulting in enhanced doxorubicin release as observed in in vitro release studies, where ∼90% doxorubicin release was achieved in pH 5.0 in the presence of 10 mM glutathione (GSH) as compared to ∼20% drug release in pH 7.4. Folic acid and trastuzumab mediated active targeting resulted in improved cellular uptake and enhanced apoptosis in in vitro studies in breast cancer cell lines. In vivo studies in Ehrlich ascites tumor bearing Swiss albino mice showed enhanced antitumor efficacy and minimal cardiotoxicity of polymersomes with ∼90% tumor regression as compared to ∼38% tumor regression observed with free doxorubicin. The results highlight therapeutic potential of the polymersomes as doxorubicin delivery nanocarrier in breast cancer therapy with its superior antitumor efficacy and minimal cardiotoxicity.