This work presents a 3D-printed, modular, electrochemical sensor-integrated transwell system for monitoring cellular and molecular events in situ without sample extraction or microfluidics-assisted downstream omics. Simple additive manufacturing techniques such as 3D printing, shadow masking, and molding are used to fabricate this modular system, which is autoclavable, biocompatible, and designed to operate following standard operating protocols (SOPs) of cellular biology. Integral to the platform is a flexible porous membrane, which is used as a cell culture substrate similarly to a commercial transwell insert. Multimodal electrochemical sensors fabricated on the membrane allow direct access to cells and their products. A pair of gold electrodes on the top side of the membrane measures impedance over the course of cell attachment and growth, characterized by an exponential decrease (~160% at 10 Hz) due to an increase in the double layer capacitance from secreted extracellular matrix (ECM) proteins. Cyclic voltammetry (CV) sensor electrodes, fabricated on the bottom side of the membrane, enable sensing of molecular release at the site of cell culture without the need for downstream fluidics. Real-time detection of ferrocene dimethanol injection across the membrane showed a three order-of-magnitude higher signal at the membrane than in the bulk media after reaching equilibrium. This modular sensor-integrated transwell system allows unprecedented direct, real-time, and noninvasive access to physical and biochemical information, which cannot be obtained in a conventional transwell system.

这项工作提出了一种 3D 打印、模块化、电化学传感器集成的 transwell 系统，用于原位监测细胞和分子事件，无需样品提取或微流体辅助下游组学。简单的增材制造技术（例如 3D 打印、遮蔽和成型）用于制造这种模块化系统，该系统可高温高压灭菌、生物相容，并设计为按照细胞生物学的标准操作协议 (SOP) 进行操作。该平台集成了一个柔性多孔膜，它用作细胞培养基质，类似于商业化的 transwell 插入物。在膜上制造的多模式电化学传感器允许直接访问细胞及其产品。膜顶部的一对金电极测量细胞附着和生长过程中的阻抗，由于分泌的细胞外基质 (ECM) 蛋白的双层电容增加，其特点是指数下降（10 Hz 时约 160%）。循环伏安法 (CV) 传感器电极制造在膜的底部，无需下游流体学即可检测细胞培养部位的分子释放。对二茂铁二甲醇注入跨膜的实时检测显示，在达到平衡后，膜上的信号比散装介质中的信号高三个数量级。这种集成传感器的模块化 transwell 系统允许前所未有的直接、实时和非侵入性访问物理和生化信息，这是传统 transwell 系统无法获得的。