Fabrication of laser printed microfluidic paper-based analytical devices (LP-µPADs) for point-of-care applications

Abstract

Microfluidic paper-based analytical devices (µPADs) have provided a breakthrough in portable and low-cost point-of-care diagnostics. Despite their significant scope, the complexity of fabrication and reliance on expensive and sophisticated tools, have limited their outreach and possibility of commercialization. Herein, we report for the first time, a facile method to fabricate µPADs using a commonly available laser printer which drastically reduces the cost and complexity of fabrication. Toner ink is used to pattern the µPADs by printing, without modifying any factory configuration of the laser printer. Hydrophobic barriers are created by heating the patterned paper which melts the toner ink, facilitating its wicking into the cross-section of the substrate. Further, we demonstrate the utilization of the fabricated device by performing two assays. The proposed technique provides a versatile platform for rapid prototyping of µPADs with significant prospect in both developed and resource constrained region.

Hybrid 3D printed-paper microfluidics

“…Devices were developed from conceptualization to use in as little as 1 h without the need for photomasks or any specialized equipment except for a commercially available FDM printer. These print times are somewhat longer and more expensive than other commonly-used hydrophobic µPAD materials such as wax 28 – 32 and ink resins 33 , 34 , but the numerous substrates capable of being 3D-printed allows barrier materials to be chosen based on application. For instance, materials can be printed that exhibit low bioanalyte absorption unlike polydimethylsiloxane 35 or those that are compatible with organic solvents unlike many waxes or chemical modification methods 36 .…”

Microfluidic Point-of-Care Testing: Commercial Landscape and Future Directions

“…With global competition and a constant time pressure, establishing a dominant position in the market can be time consuming as it requires lengthy clinical validation studies, complex regulatory approvals and slow clinical adoption (Chin et al, 2012 ). Another key aspect preventing promising technology to convert into a commercial product is the lack of standardization, which increases the complexity of manufacturing these devices making the entire manufacturing process labor intensive with increased production cost (Mohammed et al, 2015 ; Ghosh et al, 2019 ). Complexity in manufacturing & integrating several components together also thwart the process of large-scale production (Becker, 2009 ; Mohammed et al, 2015 ; Ghosh et al, 2019 ).…”

Microfluidic Point-of-Care Devices: New Trends and Future Prospects for eHealth Diagnostics

“…Paper-based microfluidic devices appear to be advantageous for their cost effectiveness, capillary fluid-flow (power-free), high surface-area-to-volume ratio, and the ability to store reagents in active form within the fiber network [42]. Microfluidic channels have been produced through an automated laser printer deposition of hydrophobic ink on paper for PoC applications [43], as illustrated in Figure 1A. Permanent fixation of the hydrophobic barriers on the cellulose's capillaries of the paper is reached upon heating at 165 • C for 15 min, as depicted in the cross-section view at the bottom of Figure 1A.…”