Fabrication of an integrated PDMS microchip incorporating an LED-induced fluorescence device

A microfluidic device with an integrated fluorescence detection system has been developed in order to miniaturize the entire analytical system. A blue or green light-emitting diode (LED) and an optical fiber were mounted in a polydimethylsiloxane-based microchip. The performance of this device was evaluated by microchip electrophoresis. When a green LED was used as the light source, the calibration curve of Sulforhodamine-101 was linear over the range 1–100 M. The detection limit was found to be 600 nM (240 amol) for a S/N ratio of 3. When using a blue LED, the calibration curve of Fluorescein was linear over the range 0.2–100 M. The detection limit was estimated to be 120 nM (50 amol) (S/N=3). The detection sensitivity per unit power was comparable to that of LIF. The RSD values for the migration time, peak height and peak area were 0.74, 7.18 and 9.45%, respectively. The integrated microfluidic device was successfully used to determine amino acid derivatives.     

高性能聚偏氟乙烯基柔性压电材料的设计策略进展

压电现象在新能源开发、 传感、 医药材料设计及可穿戴电子设备中具有广泛的潜在应用, 并受到普遍重视. 在压电材料中, 聚偏氟乙烯(PVDF)及其共聚物因具有良好的柔韧性、 易加工性、 稳定性和生物相容性等优点而备受关注. 本文综合评述了近年来在制备工艺和材料复合两个维度提高PVDF基压电材料输出性能的研究进展. 在研究PVDF压电性原理的基础上, 阐释了流延法、 静电纺丝法、 拉丝法及纳米限域策略等工艺和添加小分子、 高分子、 石墨类粒子及无机纳米粒子等复合策略提升其压电性能的机理. 这些制备工艺的提高和填料的掺杂有助于偶极子的排列和高β相的形成. 最后, 对目前存在的一些挑战进行了概述和讨论, 并对PVDF基材料的发展前景提出展望.     

Functional Poly(ionic liquid) Porous Membranes: From Fabrications to Advanced Applications†

Polyelectrolyte porous membranes (PPMs) belong to the most interesting classes of materials, because the synergy of tunable pore sizes and charge nature of polyelectrolyte endow them with wide-ranging practical applications. However, owing to the water solubility and ionic nature of the polyelectrolytes, traditional polyelectrolytes are difficult to use in scalable preparation of high-quality PPMs through the well-developed industrial methods. Poly(ionic liquid)s (PIL) are a subclass of functional polyelectrolytes bearing ionic liquid groups in their repeating unites, inheriting the advantages of ionic liquids (ILs) and macromolecular architecture features. In recent years, along with rapid development of PIL materials chemistry, considerable and significant developments involving the novel preparation methods, and structure-property-function relationships of PPMs have been made. In this review, we highlight the latest discovery and proceedings of PPMs, particularly the advancements in how to tailor structures and properties of PPMs by rational structure design of PILs. The formation mechanisms of various PPMs were also discussed in detail from the viewpoint of PILs molecular structures. A future perspective of the challenges and promising potential of PPMs is cast on the basis of these achievements. We expect that these analyses and deductions will be useful for the design of useful PPMs and serve as a source of inspiration for the design of future multifunctional PPMs.