荧光

Abstract(#br)We present a microfluidic cell plate for endocrine disrupting chemicals (EDCs) detection, like estrogenic activity, in waterish solution. This platform technology consists of four independent micro flow units made of polydimethylsiloxane (PDMS) and glass, which enables a selective detection of up to four species of the EDCs per one-way chip containing the corresponding immobilized receptor. The concept of the detection is based on direct fluorescence analysis.

Abstract(#br)This work describes a quantitative method to detect DNA damage in the presence of Pb and Cd ions using a surface modified microarray chip and a laser induced fluorescence microscopy (LIFM). The detection was carried out by the immobilization of a single-stranded DNA oligomer, tagged with a Cy5 fluorophore on a polydimethylsiloxane (PDMS) microarray chip followed by LIFM. Sulfosuccinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (Sulfo-SMCC) was attached as a cross-linker via the formation of covalent amide bonds.

Abstract(#br)In this work, a simple, flexible and low-cost sample-introduction technique was developed and integrated with droplet platform. The sample-introduction strategy was realized based on connecting the components of positive pressure input device, sample container and microfluidic chip through the tygon tubing with homemade polydimethylsiloxane (PDMS) adaptor, so the sample was delivered into the microchip from the sample container under the driving of positive pressure.

多环芳烃( PAHs )代表一类有机物。鱼油已被确定为食品中持久性有机污染物水平的最重要贡献者之一。事实上，由于鱼类的代谢能力较低，鱼油中可能含有较高水平的亲脂性污染物，如PAHs。鱼油中PAHs的测定由于脂肪基质的存在而比较复杂，对提取效率和分析数据质量都有不利影响。利用织物相吸附萃取( FPSE )从营养补充剂中成功提取目标化合物，为洗脱PAHs，将制备好的溶胶-凝胶苯基/聚二甲基硅氧烷( PDMS )涂层织物相吸附萃取膜用乙腈反萃取，洗脱后的样品用荧光检测的高效液相色谱( HPLC )分析。PAHs在C18 125×4 mm，5μm色谱柱上洗脱，烘箱温度30℃，乙腈和水梯度洗脱。分别在270和390 nm波长处测定芘和芘，290和430 nm波长处测定苯并( a )芘，方法的线性范围(芘和芘2.5 ~ 75 ng / m L，苯并( a )芘2.5 ~ 100 ng / m L )、精密度和真实性(日内和日间)、回收率( 63.2 % ~ 102.3 % )均得到验证。本工作首次提出了一种新的FPSE采样/样品清理程序，该程序最近在生物、环境、化妆品和食品基质的分析中显示了其优势。

一种简单而高效的机械变色设计是基于在含有荧光染料的聚二甲基硅氧烷( PDMS )基底上由溅射镀金属光屏蔽层构成的双层结构，拉伸时呈现横向和/或纵向微尺度裂纹。拉伸/释放时光屏蔽层上的裂纹张开宽度使得紫外辐射激活PDMS基体中的荧光染料表现出发光颜色，可以随荧光染料的选择而方便地调谐。在制备过程中施加不同程度的预拉伸应变，可以对裂纹张开宽度的应变响应进行微调，从而产生可定制的机械变色响应。制备了三种机械色器件作为典型的例子。这些器件的荧光强度可以随应变的增大而增大或减小，或者在工作应变范围内先减小后增大。此外，该系统还可以进一步修改为具有数字显示功能的动态应变传感器，使设备的应变程度可以直接读取。这种设计策略很容易被其他研究人员采用，有望为各种动态自适应光学的机械色响应调节开辟一条全新的途径。