3D Printed Microfluidic Probes

Abstract

In this work, we fabricate microfluidic probes (MFPs) in a single step by stereolithographic 3D printing and benchmark their performance with standard MFPs fabricated via glass or silicon micromachining. Two research teams join forces to introduce two independent designs and fabrication protocols, using different equipment. Both strategies adopted are inexpensive and simple (they only require a stereolithography printer) and are highly customizable. Flow characterization is performed by reproducing previously published microfluidic dipolar and microfluidic quadrupolar reagent delivery profiles which are compared to the expected results from numerical simulations and scaling laws. Results show that, for most MFP applications, printer resolution artifacts have negligible impact on probe operation, reagent pattern formation, and cell staining results. Thus, any research group with a moderate resolution (≤100 µm) stereolithography printer will be able to fabricate the MFPs and use them for processing cells, or generating microfluidic concentration gradients. MFP fabrication involved glass and/or silicon micromachining, or polymer micromolding, in every previously published article on the topic. We therefore believe that 3D printed MFPs is poised to democratize this technology. We contribute to initiate this trend by making our CAD files available for the readers to test our “print & probe” approach using their own stereolithographic 3D printers.

Microfluidic multipoles theory and applications

“…To validate our theoretical model, multipolar microfluidic devices were fabricated using a previously published single step 3D rapid prototyping process 23 , which offers several advantages over conventional silicon-based machining: it is fast and simple, and truly 3D structures can be produced, which allows the fabrication of compact MFM with high density of fluidic ports that are connected via complex fluidic routing architectures to arbitrarily positioned apertures. MFM devices can be operated in scanning probe mode, as MFPs.…”

“…Tygon tubes (Cole Parmer, Vernon Hills, USA) were then plugged and glued to the MFMs using cyanoacrylate glue. The fabrication method is further described in a previously published article 23 . MFMs with auto-alignment pillars required no active component and were simply clamped on a glass slide using a simple 3D printed setup and a spring.…”

“…Moreover, single block printing of microfluidic devices affords full design flexibility in three dimensions that can simply not be realized using microfabrication processes dependent on iterative photolithography and microstructuring cycles. We recently presented a method for 3D printing of MFMs 23 , but a proof of concept for the fabrication of more general open-space microfluidic devices is still missing.…”

A Microfluidic Probe Integrated Device for Spatiotemporal 3D Chemical Stimulation in Cells

“…Although the methods using laminar flow have great spatial resolution in a vertical flow direction, the spatial resolution in the horizontal flow direction is quite low. A microfluidic probe (MFP) is a non-contact technology that has been proposed to regulate the microenvironment surrounding the targeted cells [16][17][18]. An MFP has two microchannels, one for injection and the other for aspiration.…”

Integrating 3D cell culture of PC12 cells with microchip-based electrochemical detection

“…Use of 3D printing technologies is becoming popular for both public interest reasons and for those doing microfluidics. [7][8][9][10][11] The development of commercially available 3D printed plastics and metals has helped bring the cost of 3D printing down to a price point that has made it useful for microfluidic researchers. Examples of this work includes work done by Chen et.…”