Microfluidic Actuation via 3D-Printed Molds toward Multiplex Biosensing of Cell Apoptosis

Abstract

Multiplexed analysis of biochemical analytes such as proteins, enzymes, and immune products using a microfluidic device has the potential to cut assay time, reduce sample volume, realize high-throughput, and decrease experimental error without compromising sensitivity. Despite these huge benefits, the need for expensive specialized equipment and the complex photolithography fabrication process for the multiplexed devices have, to date, prevented widespread adoption of microfluidic systems. Here, we present a simple method to fabricate a new microfluidicbased multiplexed biosensing device by taking advantage of 3D-printing. The device is an integration of normally closed (NC) microfluidic valving units which offer superior operational flexibility by using PDMS membrane (E ∼ 1−2 MPa) and require minimized energy input (1−5 kPa). To systematically engineer the device, we first report on the geometrical and operational analysis of a single 3D-printed valving unit. Based on the characterization, we introduce a full prototype multiplexed chip comprising several microfluidic valves. The prototype offers for the first time in a 3D-printed microfluidic devicethe capability of on-demand performce of both a sequential and a parallel biochemical assay. As a proof of concept, our device has been used to simultaneously measure the apoptotic activity of 5 different members of the caspase protease enzyme family. In summary, the 3D-printed valving system showcased in this study overcomes traditional bottlenecks of microfabrication, enabling a new class of sophisticated liquid manipulation required in performing multiplexed sensing for biochemical assays.

Recent Advances in Chemically Engineered Nanostructures Impact on Ischemic Stroke Treatment

“…It is essential for fetal development, immune regulation, and tissue growth. The nucleus, mitochondria, and plasma membrane are among the intracellular structures that are destroyed during apoptosis by a group of protease enzymes called caspases . Apoptosis can still happen even though caspase activity is not required for apoptosis to occur because of the important role that caspases play in controlling programmed cell death.…”

Oncoimmunology Meets Organs-on-Chip

“…Here a paper-based immunosensor has been generated, coupled to a fluidic chamber to propagate the fluid toward the sensor area in which the CA125 protein will be detected by an ELISAbased assay (Bahavarnia et al, 2019). Similar approaches based on the immunosensors have been described in literature, useful to study apoptotic activity (Dang et al, 2019) or soluble immune checkpoint inhibitors (Reza et al, 2019) in biological fluids or clinical samples. These studies represent interesting examples of LCs to be applied for oncoimmunology applications.…”

Study on the Preparation and Test of Hydrodynamic Focusing Microfluidic Chip Fabricated by Liquid Crystal Display Mask Photo-Curing Method

“…Currently, the additive manufacturing method used for microfluidic chip processing mainly includes fused deposition manufacturing and ultraviolet (UV) curing methods, each method contains many branches. Dang et al [12] presented a simple method to fabricate a new microfluidic-based multiplexed biosensing device by combining the FDM and the molding process. The device is an integration of normally closed microfluidic valving units which offer superior operational flexibility by using polydimethylsiloxane (PDMS) membrane and require minimized energy input.…”