鲍鱼多糖Hal-B的乙酰解研究

对鲍鱼中分离得到的硫酸脂多糖Hal—B进行了乙酰解的研究。硅胶柱层析分离得到两个组分，核磁共振和串联质谱的研究表明：这两个组分分别是全乙酰化的半乳糖和全乙酰化的寡糖混合物。     

网状纳米结构α-Fe2O3薄膜的电喷雾制备

采用自建的电喷雾装置, 以浓度为10^-6mol/L的Fe(NO₃)₃和HAuCl₄混合溶液为前驱液, 在FTO(掺杂F的SiO₂玻璃)上沉积网状纳米结构的α-Fe₂O₃薄膜， 并分别用X射线衍射（XRD）、 Raman光谱、 扫描电子显微镜（SEM）、 能量色散X射线荧光光谱仪（EDX）、 X射线光电子能谱分析（XPS）和气敏测试对所得薄膜的组成、 结构和性能进行表征. 结果表明： 所得网状纳米结构由α-Fe₂O₃纳米粒子堆积而成； 喷雾过程中氯金酸的浓度和沉积时间对网状结构的形貌具有调控作用； 电喷雾法具有原料消耗少、 产物分散度高等优点.     

电喷雾质谱法研究酸和盐诱导下蛋白质的折叠状态的改变

电喷雾质谱正离子模式研究了在酸和盐的诱导下蛋白质的折叠状态.研究表明,用酸去折叠后的溶菌酶在相同电喷雾质谱条件中有表现出比紧密折叠的蛋白质相对低的电荷状态,而细胞色素C的电荷状态却相反.在相当宽的挥发性盐浓度范围内,电喷雾质谱对蛋白质的检测都表现出良好的信号,而在高盐浓度下,传统的检测方法如圆二色谱则无法检测,这一结果为高盐浓度的下蛋白质的研究提供一个手段.同时考察了主要仪器条件的设定对测定的影响.     

麻黄生物碱类化合物电喷雾电离质谱

采用电喷雾离子阱质谱(ESI-MS)法,研究了麻黄生物碱类化合物的质谱行为及分子结构与裂解规律间的关系．样品通过直接进样,进行一级质谱正负离子全扫描(扫描范围m／z：50～800)和选择性离子二级质谱分析(扫描范围m／z：50～200)．流动相：甲醇一水(50：50V/V),流速：0．2mL／min,离子源喷雾电压：4．5kV;毛细管温度：200℃,鞘气流速：40个单位．结果显示,该类化合物在电喷雾电离一级质谱中易得到质子产生正离子,并有部分自发丢失小分子H20的碎片产生．应用碰撞诱导解离(CID)技术得到的二级质谱显示,麻黄生物碱侧链氮原子比较活跃,质谱碰撞容易失去连接在N原子上的取代基团,特征性丢失为CH2、CH4、NH4、NH2等中性碎片．一级、二级质谱图适宜作为麻黄生物碱提取物特征图谱,实验结果可应用于麻黄生物碱类化合物的结构分析研究,并为麻黄药材有效成分的鉴定提供了一种快速、准确的检测方法．     

四溴双酚A和甲状腺素运载蛋白复合物的电喷雾质谱研究

为阐明四溴双酚A(TBBPA)的内分泌干扰机制,构建了电喷雾质谱法研究四溴双酚A和甲状腺素运载蛋白(TTR)的相互作用,考察了电喷雾离子源条件对TTR蛋白和TTR蛋白质复合物多电荷峰的影响,证明了电喷雾质谱是研究蛋白质多聚体和蛋白质复合物的有力工具.结果表明:在温和的电喷雾电离条件下,四溴双酚A和TTR蛋白可形成稳定的摩尔比为1︰1和2︰1复合物,影响TTR蛋白和天然底物甲状腺素(T4)的结合,干扰甲状腺素在生物体内的正常运输和生理功能.     

Compound-fluidic electrospray: An efficient method for the fabrication of microcapsules with multicompartment structure

Microcapsules with multiple compartments are of significant importance in many applications such as smart drug delivery, microreactor, complicated sensor, and so on. Here we report a novel compound-fluidic electrospray method that could fabricate multicompartment microcapsules in a single step. The as-prepared microcapsules have multiple compartments inside. The compartments are separated from each other by inner walls made from shell materials, and different content can be independently loaded in each of them without any contact. We assemble a hierarchical compound nozzle by inserting certain numbers of metallic inner capillaries separately into a blunt metal needle. The particular configuration of the compound nozzle induces a completely and independently envelope of core fluids by shell fluid, as a result of which mulicomponent microcapsules with multicompartment structure can be obtained. And also, the number of inner compartments and the corresponding encapsulated components can be controlled by rationally designing the configuration of the compound nozzle. This general method can be readily extended to many other functional materials, especially for the effective encapsulation of active ingredients, such as sensitive and reactive materials.     

Advances and applications of electrohydrodynamics

Electrohydrodynamics (EHD) has been applied in many areas, such as EHD enhanced heat transfer, EHD pump, electrospray mass spectrometry, electrospray nanotechnology, etc. The basic theories underlying these applications and a brief review of the EHD advances are presented in this paper. As electrospray is an important branch of EHD,the applications of electrospray are particularly discussed.Finally, this paper gives some suggestions for the future research and development.     

PZT溶胶液静电雾化雾场模拟

通过对商用计算流体力学软件FLUENT进行功能扩展，实现了空气流场、空间电场和离散雾场多场耦合过程的数值模拟．由实验数据确定雾滴的滴径和电量，采用拉格朗日模型计算雾滴在重力、空气阻力、外部电场力及雾滴间相互库伦排斥力作用下的运动轨迹，并得到雾滴的速度与其空间分布密度，由此计算雾滴在衬底上的沉积通量．     

电喷法制备多功能壳聚糖微球

文章通过电喷法制备了包含磁性和荧光性能的多功能壳聚糖微球,该多功能壳聚糖微球可以对外加磁场做出快速响应。在荧光显微镜下可以观察到微球会发出强的荧光,在不同波长的激发光激发下,能够依次发绿色、黄色、红色的荧光。微球的平均尺寸约为3μm,分布均一、形貌规整。该研究为制备多功能的壳聚糖微球提供了新的方法。     

The role of apolipoprotein E in lipid metabolism in the central nervous system

The critical roles of apolipoprotein E (apoE) in regulating plasma lipid and lipoprotein levels have been extensively studied for over 2 decades. However, an understanding of the roles of apoE in the central nervous system (CNS) is less certain. This review will summarize the available experimental results on the role of apoE in CNS lipid homeostasis with respect to its modulation of sulfatide trafficking, alteration of CNS cholesterol homeostasis and apoE-induced changes in phospholipid molecular species in specialized subcellular membrane fractions. The results indicate that apoE mediates sulfatide trafficking and metabolism in the CNS. Moreover, although apoE does not affect the cholesterol mass content or the phospholipid mass levels and composition in the CNS as a whole, apoE modulates cholesterol and phospholipid homeostasis in selective subcellular membrane compartments. Through elucidating the roles of apoE in CNS lipid metabolism, new insights into overall functions of apoE in neurobiology can be accrued ultimately, leading to an increased understanding of CNS lipid metabolism and the identification of novel therapeutic targets for CNS diseases.Received 9 January 2004; received after revision 28 February 2004; accepted 10 March 2004