One-Step Fabrication of a Microfluidic Device with an Integrated Membrane and Embedded Reagents by Multimaterial 3D Printing

Abstract

One of the largest impediments in the development of microfluidic-based smart sensing systems is the manufacturability of integrated, complex devices. Here we propose multimaterial 3D printing for the fabrication of such devices in a single step. A microfluidic device containing an integrated porous membrane and embedded liquid reagents was made by 3D printing and applied for the analysis of nitrate in soil. The manufacture of the integrated, sealed device was realized as a single print within 30 min. The body of the device was printed in transparent acrylonitrile butadiene styrene (ABS) and contained a 400 μm wide structure printed from a commercially available composite filament. The composite filament can be turned into a porous material through dissolution of a water-soluble material. Liquid reagents were integrated by briefly pausing the printing before resuming for sealing the device. The devices were evaluated by the determination of nitrate in a soil slurry containing zinc particles for the reduction of nitrate to nitrite using the Griess reagent. Using a consumer digital camera, the linear range of the detector response ranged from 0 to 60 ppm, covering the normal range of nitrate in soil. To ensure that the sealing of the reagent chamber is maintained, aqueous reagents should be avoided. When using the nonaqueous reagent, the multimaterial device containing the Griess reagent could be stored for over 4 days but increased the detection range to 100-500 ppm. Multimaterial 3D printing is a potentially new approach for the manufacture of microfluidic devices with multiple integrated functional components.

3D Printing in analytical sample preparation

“…Relying on the porous property of the printing material, separation membranes can be fabricated directly via different 3D printing techniques. Breadmore's group utilized an FDM 3D printer for direct separation membrane fabrication [32,36–38]. A microfluidic device with a printed integrated membrane was fabricated using a multi‐material FDM printer for direct colorimetric analysis of nitrate in the soil as shown in Figure 3.…”

“…To date, 3D printing has contributed to the improvement of devices for SPE using directly the 3D printed material as extraction sorbent [26], or as holders to pack conventional sorbents [30]. 3D printing has also been used to facilitate LLE [31], and membrane separation [32] (Figure 2). Different reviews have been published covering the applications and potential of 3D printing in the field of analytical chemistry, including separation science [33,34], and online sample handling [35].…”

3D Micropatterned All‐Flexible Microfluidic Platform for Microwave‐Assisted Flow Organic Synthesis

“…3D printing has been used in the area of microfluidics to fabricate microfluidic networks and chips utilizing microvascular networks, for tissue engineering and for chemical synthesis applications . Also, 3D printed mesoreactors have been reported in the literature .…”

“…These are:1 )inkjet 3D printing in which both drop-on-demand and continuous printing modes are applicable, [25] 2) stereolithography,i nw hich objects are printed layer-by-layer using photo-polymerization of monomers, [26] and 3) the two-photon polymerization method, in which near-infrared femtosecond laser irradiation is applied to amaterial for polymerization. [27,28] 3D printing has been used in the area of microfluidics [29,30] to fabricate microfluidic networks andc hips utilizing microvascular networks, [29] for tissue engineering [31][32][33][34] and for chemical synthesis applications. [35] Also, 3D printed mesoreactors have been reported in the literature.…”

A Printed Equilibrium Dialysis Device with Integrated Membranes for Improved Binding Affinity Measurements

“…In a recent example of overcoming such obstacles, innovative work by Breadmore et al described successful use of a multiple-material FDM 3D printer to integrate a polymer Lay–Felt membrane directly into a microfluidic device without leakage. 25 Here, we describe a novel and simple Print–Pause–Print technique for seamlessly integrating any membrane directly into 3D-printed devices via a polyjet printer without the use of adhesives or O-rings. The device, which was developed for measuring the equilibrium-binding constants of important biological ligands to a carrier protein, enables the user to choose any membrane for their experiments.…”