Influence of Structural Features on the Cellular Uptake Behavior of Non‐Targeted Polyester‐Based Nanocarriers

The development of delivery systems efficiently uptaken by cells is of due importance since sites of drug action are generally localized in subcellular compartments. Herein, naked and core–shell polymeric nanoparticles (NPs) have been produced from poly(lactic‐co‐glycolic acid)—PLGA, poly(ethylene oxide)‐b‐poly(ε‐caprolactone)—PEO‐b‐PCL, and poly(ethylene oxide)‐b‐poly(lactic acid)—PEO‐b‐PLA. The nanostructures are characterized and the cellular uptake behavior is evaluated. The data evidence that cellular uptake is enhanced as the length of the hydrophilic PEO‐stabilizing shell reduces and that high negative surface charge restricts cellular uptake. Furthermore, NPs of higher degree of hydrophobicity (PEO‐b‐PCL) are more efficiently internalized as compared to PEO‐b‐PLA NPs. Accordingly, taking into account our recent published results 1 and the findings of the current investigation, there should be a compromise regarding protein fouling and cellular uptake as resistance to nonspecific protein adsorption and enhanced cellular uptake are respectively directly and inversely related to the length of the PEO‐stabilizing shell.

     

准固态染料敏化太阳能电池中电解质体系的研究进展

染料敏化太阳能电池(Dye Sensitized Solar Cells)是新一代将光能转化为电能的重要能源转换装置。它具有低廉的材料和器件制作成本、较高的光电转换效率以及电池制作过程简单等诸多优点,拥有广阔的应用空间和巨大的潜在商业价值,因而吸引了广泛的研究关注。染料敏化太阳能电池主要由染料敏化的光阳极、电解质和对电极三个部分组成。其中,电解质作为染料敏化太阳能电池的重要组成部分,其对离子的传导和扩散,以及促进染料再生的能力极大地影响着染料敏化太阳能电池的电荷传输和光电性能。本文聚焦于染料敏化太阳能电池准固态电解质体系,主要从聚合物凝胶电解质、有机小分子凝胶电解质和无机纳米粒子凝胶电解质三大方面综述讨论了该研究领域当前最新研究进展,并对其未来研究趋势进行了展望。     

染料聚集态中空穴传递的顺磁共振研究

本文应用了顺磁共振波谱技术,研究了染料J-聚集体对染料正空穴俘获电子的影响。实验所用乳剂是未经化学增感的溴化银(AgBr),染料用量2.5×10^-4摩尔染料/摩尔银。涂片厚度为3微米左右。     

纳米银粒子表面包覆分子共振吸收峰的红移现象

本文首次发现了两种电性不同的染料分子若丹明6G及荧光素钠包覆纳米银粒子时,染料分子共振吸收峰的红移现象,以及产生红移的条件。前者只有在KC1、KBr、KI等电解质存在时才产生红移;而后者则无需这些电解质存在。其红移量分别为27um及13nm.并对产生红移的机理进行了讨论。     

固态类杂芪分子一阶超极化率测定及溶剂效应

用溶致变色法研究溶剂对反式－（４－Ｎ,Ｎ－二甲氨基）－（４－Ｎ－甲基吡啶基）杂芪碘（ＤＡＳＰＩ）、反式、（２－Ｎ－比咯基）－（４－Ｎ－甲基吡啶基）杂芪碘３＊（ＭＰＰＳＩ）,反式－２（２－吡咯基）－２（４－Ｎ－比啶基）杂芪磺（ＰＰＳＩ）、反式－（２－呋喃基）－（４－Ｎ＿甲基吡啶基）杂芪碘（ＦＰＳＩ）、反式－（２－噻吩基）－（４－Ｎ－甲基吡啶基）杂芪磺（ＴＰＳＩ）和反式＿４－Ｎ－Ｌ在吡啶基）杂芪碘（Ｐ     

Pulse Duration Dependent Asymmetry in Molecular Transmembrane Transport Due to Electroporation in H9c2 Rat Cardiac Myoblast Cells In Vitro

Electroporation (EP) is one of the successful physical methods for intracellular drug delivery, which temporarily permeabilizes plasma membrane by exposing cells to electric pulses. Orientation of cells in electric field is important for electroporation and, consequently, for transport of molecules through permeabilized plasma membrane. Uptake of molecules after electroporation are the greatest at poles of cells facing electrodes and is often asymmetrical. However, asymmetry reported was inconsistent and inconclusive—in different reports it was either preferentially anodal or cathodal. We investigated the asymmetry of polar uptake of calcium ions after electroporation with electric pulses of different durations, as the orientation of elongated cells affects electroporation to a different extent when using electric pulses of different durations in the range of 100 ns to 100 µs. The results show that with 1, 10, and 100 µs pulses, the uptake of calcium ions is greater at the pole closer to the cathode than at the pole closer to the anode. With shorter 100 ns pulses, the asymmetry is not observed. A different extent of electroporation at different parts of elongated cells, such as muscle or cardiac cells, may have an impact on electroporation-based treatments such as drug delivery, pulse-field ablation, and gene electrotransfection.     

Density Functional Theory Study on Organic Dye Sensitizers Containing Bis-dimethylfluorenyl Amino Benzofuran

运用密度泛函理论和含时密度泛函理论研究了两种含二-二甲基芴氨基苯并呋喃基团的有机染料敏化剂的几何结构、电子结构、极化率和超极化率以及紫外可见谱. 基于理论计算和实验结果的一致性指认了电子吸收谱的特征. 可见区的吸收带都与光诱导电荷转移过程有关,二甲基芴氨基苯并呋喃基团是在光电转换敏化中起主要作用的基团. 通过对两种染料敏化剂的比较,分析了亚乙烯基对几何结构、电子结构和光谱特性影响.     

清末传世纺织品的材质鉴别和所用染料的微量分析

从早期纺织品保护的视角出发,通过对这一行业国内外大量文献资料梳理分析,对比了织物的常规系统分析方法,结合现代的科学技术方法,对早期纺织品的面料种类、所用染料种类以及染色工艺进行测定分析。面对目前服饰博物馆清末传世朱红女袄保藏面临的严峻考验,运用傅里叶变换红外光谱仪鉴定该纺织品的材质,以萃取法提取纺织品上的染料,用反射分光色度仪对提取前后的纺织品进行表面颜色分析,并用高压液相色谱和质谱对色素进行结构分析,尝试确定分析早期纺织品上染料的结构成分和上染方式。将现代分析技术（液质联用）和理念（色度学）融入传统研究中,使用客观科学技术获取更多有效数据和信息,佐证以主观目鉴方法得出的结论,弥补这一研究领域的空白,使对于传统服饰的研究更具深度。与传统的纺织品鉴别方法横向比较,现代的科学技术方法获得的相关信息更加详尽可靠。有利于根据不同染料特性和不同纤维种类特性提出具有针对性的保藏措施,对博物馆馆藏纺织品的保护和保存具有重要的意义。采用傅里叶变换红外仪对样品的面料进行简单分析,通过不同的特殊特征峰确定了样品为蚕丝面料。该研究建立了一种普遍适用的染料提取方法,采用丙酮、乙腈、吡啶：水（1∶1）、N,N-二甲基甲酰胺、0.1%乙二胺四乙酸水溶液/N,N-二甲基甲酰胺（1∶1）、甲醇六种不同的溶剂提取样品上的染料,采用反射分光光度仪对样品表面剥色前后的颜色进行色度测量分析。结果表明,吡啶的水溶液对染料具有最佳的提取效果;发现提取染料时加入少量乙二胺四乙酸,会提高剥色效率,即染色方式可能是媒染法,因为乙二胺四乙酸可以破坏染料和媒染金属离子间的络合作用。从染料提取前后织物的颜色变化可以推断样品的颜色可能是由染料拼色得到,利用液质联用技术（LC-MS）对提取的染料进行检测,根据染料上染方式和分子量推测分析,纺织品上染料可能含有小檗碱。经过标准小檗碱染料进行验证,进一步证明了染色纺织品上其中一种染料为小檗碱。     

Four Coordination Polymers Assembled with a New Biscarboxyl-functionalized Schiff Base Ligand

Based on a new biscarboxyl-functionalized Schiff base ligand 1,2-cyclohexanediamino-N,N'-bis[3-methoxyl-5-(p-carboxyl-phenylazo)] salicylidene(H₄L), four polymers,[(CH₃)₂NH₂]₂·[Mn₃(L)₂(H₂O)₄]·2DMF(CP1),[Fe₂(L)(H₂O)(DMF)](CP2),[(CH₃)₂NH₂]·[Cu(HL)]·H₂O(CP3) and[Ni₂(L)(teta)]·2DMF·H₂O(CP4), have been synthesized(teta=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane). In CP1, both of the internal[N₂O₂] pocket and the external carboxylate groups of L^4- anion are ligated by Mn²⁺ ions, and the structure displays a layer. In CP2, the Fe²⁺ cations are linked by L^4- anions to form a binuclear double chain. CP3 displays a[Cu₂(HL)₂] dimer. In CP4, the Ni²⁺ ions are connected by L^4- anions to form a chain. The structures are further linked by hydrogen bonds to form 2D or 3D supramolecular architectures, respectively. CP1 exhibits adsorption ability to three organic dyes.