Printed microfluidic filter for heparinized blood

Inkjet Printing and 3D Printing Strategies for Biosensing, Analytical, and Diagnostic Applications

Inkjet printing and 3D inkjet printing have found many applications in the fabrication of a great variety of devices, which have been developed with the aim to improve and simplify the design, fabrication, and performance of sensors and analytical platforms. Here, developments of these printing technologies reported during the last 10 years are reviewed and their versatile applicability for the fabrication of improved sensing platforms and analytical and diagnostic sensor systems is demonstrated. Illustrative examples are reviewed in the context of particular advantages provided by inkjet printing technologies. Next to aspects of device printing and fabrication strategies, the utilization of inkjet dispensing, which can be implemented into common analytical tools utilizing customized inkjet printing equipment as well as state-of-the-art consumer inkjet printing devices, is highlighted. This review aims to providing a comprehensive overview of examples integrating inkjet and 3D inkjet printing technologies into device layout fabrication, dosing, and analytical applications to demonstrate the versatile applicability of these technologies, and furthermore, to inspire the utilization of inkjet printing for future developments.

High-Performance Passive Plasma Separation on OSTE Pillar Forest

Plasma separation is of high interest for lateral flow tests using whole blood as sample liquids. Here, we built a passive microfluidic device for plasma separation with high performance. This device was made by blood filtration membrane and off-stoichiometry thiol-ene (OSTE) pillar forest. OSTE pillar forest was fabricated by double replica moldings of a laser-cut polymethylmethacrylate (PMMA) mold, which has a uniform microstructure. This device utilized a filtration membrane to separate plasma from whole blood samples and used hydrophilic OSTE pillar forest as the capillary pump to propel the plasma. The device can be used to separate blood plasma with high purity for later use in lateral flow tests. The device can process 45 μL of whole blood in 72 s and achieves a plasma separation yield as high as 60.0%. The protein recovery rate of separated plasma is 85.5%, which is on par with state-of-the-art technologies. This device can be further developed into lateral flow tests for biomarker detection in whole blood.

Flow induced particle separation and collection through linear array pillar microfluidics device

Particle filtration and concentration have great significance in a multitude of applications. Physical filters are nearly indispensable in conventional separation processes. Similarly, microfabrication-based physical filters are gaining popularity as size-based particle sorters, separators, and prefiltration structures for microfluidics platforms. The work presented here introduces a linear combination of obstructions to provide size contrast-based particle separation. Polystyrene particles that are captured along the crossflow filters are packed in the direction of the dead-end filters. Separation of polydisperse suspension of 5 μm and 10 μm diameter polystyrene microspheres is attained with capture efficiency for larger particles as 95%. Blood suspension is used for biocharacterization of the device. A flow induced method is used to improve particle capture uniformity in a single microchannel and reduce microgap clogging to about 30%. This concept is extended to obtain semiquantification obtained by comparison of the initial particle concentration to captured-particle occupancy in a microfiltration channel.

Investigation of Bifurcation Effect on Various Microfluidic Designs for Blood Separation

In this project, a microfluidic device for blood separation will be designed and tested in order to separate plasma from whole blood for diagnostic purposes. The design will be based on previously implemented designs that will be further discussed in the next sections. When designing microfluidic devices, it is essential to consider the different physical phenomena that arise from switching from the macro scale to the micro scale. Parameters such as the Reynolds number and the forces affecting the fluid must be studied in order to produce a suitable and effective design. Finite element methods have been implemented prior to the production of the microfluidic devices. Various geometries/designs have been tested using Fluent ANSYS software. Later on, the successful design was fabricated using micromachining on an acrylic substrate and was tested using simulated blood through of a syringe pump.

3D-printed miniaturized fluidic tools in chemistry and biology

3D printing (3DP), an additive manufacturing (AM) approach allowing for rapid prototyping and decentralized fabrication on-demand, has become a common method for creating parts or whole devices. The wide scope of the AM extends from organized sectors of construction, ornament, medical, and R&D industries to individual explorers attributed to the low cost, high quality printers along with revolutionary tools and polymers. While progress is being made but big manufacturing challenges are still there. Considering the quickly shifting narrative towards miniaturized analytical systems (MAS) we focus on the development/rapid prototyping and manufacturing of MAS with 3DP, and application dependent challenges in engineering designs and choice of the polymeric materials and provide an exhaustive background to the applications of 3DP in biology and chemistry. This will allow readers to perceive the most important features of AM in creating (i) various individual and modular components, and (ii) complete integrated tools.