Sealing is one of the inevitable process in microfluidic chip fabrication to form complex networks for the biosensing applications. Currently, only a few materials can be used in microfluidic biosensor due to the lack of reliable bonding technique for most materials. To solve the problem of versatility for chip sealing, a novel adhesive bonding method as simple as “tear off–paste on” is developed. PDMS is mixed with a small amount of polyethylenimine solution to prepare a sticky thin layer, which works like a tape to paste on different materials. Various substrates including glass, plastic, metal and ceramics are used for preparation of microfluidic chips with good bonding strength. This method is appealing for its compatibility to traditional replication method using PDMS and SU8 channel mold while the small surface structures of channel walls can be retained. This method is reliable and versatile for microfluidic biosensor sealing, especially for those with biological sensitive recognition elements on the surfaces since neither aggressive chemicals, high temperature nor high-energy plasma is used. The applicability of the developed method is demonstrated to fabricate a novel long-term cell culture 3D microfluidic chip which keeps bacteria viable for more than 7 days.

密封是微流控芯片制造中形成生物传感应用复杂网络的必然过程之一。目前，由于大多数材料缺乏可靠的键合技术，因此仅有几种材料可用于微流控生物传感器。为了解决芯片密封的通用性问题，开发了一种新颖的粘合剂粘合方法，如“撕开-粘贴”。将PDMS与少量的聚乙烯亚胺溶液混合以制备粘性薄层，该粘性层的作用就像胶带一样，可以粘贴在不同的材料上。使用包括玻璃，塑料，金属和陶瓷在内的各种基材来制备具有良好结合强度的微流控芯片。此方法因其与使用PDMS和SU8通道模具的传统复制方法的兼容性而吸引人，同时可以保留通道壁的小表面结构。这种方法对于微流体生物传感器密封是可靠且通用的，特别是对于那些在表面具有生物敏感识别元素的传感器，因为没有使用腐蚀性化学物质，高温或高能等离子体。证明了所开发方法的适用性，可制造出一种新型的长期细胞培养3D微流控芯片，该芯片可使细菌存活7天以上。