State Key Laboratory of Transducer Technology, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, PR China.
Biosens Bioelectron. 2010 Sep 15;26(1):255-61. doi: 10.1016/j.bios.2010.06.041. Epub 2010 Jul 1.
An ideal microfluidic-based biosensor flow cell should have not only a "soft" interface for high strength sealing with biosensing chips, but also "hard" macro-to-micro interface for tubing connection. Since these properties are exclusive of each other, no one material can provide the advantages of both. In this paper, we explore the application of a SiO(2) thin film, deposited by plasma-enhanced chemical vapor deposition (PECVD) technology, as an intermediate layer for irreversibly adhering polydimethylsiloxane (PDMS) to plastic substrate, and develop a hard-soft, compact, robust microfluidic-based biosensor flow cell for the multi-array immunoassay application of surface plasmon resonance (SPR) imaging. This hard-soft biosensor flow cell consists of one rigid, computer numerically controlled (CNC)-machined poly(methyl methacrylate) (PMMA) base coated with a 200 nm thick SiO(2) thin film, and one soft PDMS microfluidic layer. This novel microfluidic-based biosensor flow cell does not only keep the original advantage of conventional PDMS-based biosensor flow cell such as the intrinsically soft interface, easy-to-fabrication, and low cost, but also has a rigid, robust, easy-to-use interface to tubing connection and can be operated up to 185 kPa in aqueous environments without failure. Its application was successfully demonstrated with two types of experiments by coupling with SPR imaging biosensor: the real-time monitoring of the immunoglobulin G (IgG) interaction, as well as the detection of sulfamethoxazole (SMOZ) and sulfamethazine (SMZ) with the sensitivity of 3.5 and 0.6 ng/mL, respectively. This novel hard-soft microfluidic device is also useful for a variety of other biosensor flow cells.
一种理想的基于微流控的生物传感器流动池不仅应该具有与生物传感芯片进行高强度密封的“软”接口，还应该具有用于管连接的“硬”宏观到微观接口。由于这些特性彼此排斥，因此没有一种材料可以同时具有这两种优势。在本文中，我们探索了等离子体增强化学气相沉积（PECVD）技术沉积的 SiO2 薄膜作为将聚二甲基硅氧烷（PDMS）不可逆地粘附到塑料基底上的中间层的应用，并开发了一种用于表面等离子体共振（SPR）成像的多阵列免疫分析的硬-软、紧凑、坚固的基于微流控的生物传感器流动池。这种硬-软生物传感器流动池由一个刚性的、数控机床加工的聚甲基丙烯酸甲酯（PMMA）基底组成，该基底涂有 200nm 厚的 SiO2 薄膜，以及一个软 PDMS 微流层。这种新型的基于微流控的生物传感器流动池不仅保留了传统的基于 PDMS 的生物传感器流动池的固有优势，如软界面、易于制造和低成本，而且还具有刚性、坚固、易于与管连接的接口，可以在水相环境中承受高达 185kPa 的压力而不会失效。通过与 SPR 成像生物传感器耦合，成功地用两种类型的实验证明了其应用：实时监测免疫球蛋白 G（IgG）相互作用，以及检测磺胺甲恶唑（SMOZ）和磺胺甲嘧啶（SMZ）的灵敏度分别为 3.5 和 0.6ng/mL。这种新型的硬-软微流控装置也可用于各种其他生物传感器流动池。
