Beyond Wax Printing: Fabrication of Paper-Based Microfluidic Devices Using a Thermal Transfer Printer

Abstract

Paper-based microfluidic devices, also known as microPADs, are an emerging analytical platform with the potential to improve point-of-care diagnostics. MicroPADs are fabricated by patterning hydrophobic inks onto sheets of paper to create hydrophilic channels and test zones. One of the main advantages of microPADs is that they are inexpensive and simple to fabricate, making them accessible even to researchers with limited budgets or no prior fabrication expertise. Wax printing, where a solid ink printer is used to pattern wax on paper, has been the most convenient and popular method for fabricating paper-based microfluidic devices. Unfortunately, solid ink printers were discontinued in 2016 and are no longer available commercially. Here we introduce a method for fabricating microPADs using a portable thermal transfer printer that retains the convenience of wax printing. Devices fabricated by thermal transfer printing were comparable to devices fabricated via wax printing and laser printing. The low cost, convenience, and portability of the thermal transfer printer make this approach an exciting prospect for replacing wax printing and facilitating the continued development of paper-based microfluidics.

Detection of Bile Acids in Complex Matrices Using a Transcription Factor-Based Biosensor

“…In the literature, a variety of approaches have been taken to develop point-of-use assays, such as implementing digital polymerase chain reactions on miniaturized platforms 13,14 interpret without using any specialized equipment. 15,16 Likewise, there are several reports of the development of portable biosensors that detect bile acids in serum and urine using electrochemical platforms. 17,18 However, these sensors have not yet achieved the desired functionality, in terms of either stability over time or analyte sensitivity.…”

A paper-analytical device for detecting bisphenol-A in foods

“…In addition, PADs are easy to fabricate, portable, low cost, and simple to operate, and they do not require large instruments. [14][15][16][17] Techniques such as wax printing, 18,19 stamping, 20 photolithography, 21 etching, 22 and thermal transfer printer, 23 have been used to fabricate PADs in previous literature studies. In 2007, Martinez and team members proposed a method where paper was used as a novel material for fabricating microuidic analytical devices.…”

Fully integrated colorimetric sensor based on transparency substrate for salbutamol determination

“…Since first development in 2007, the µPAD has experienced rapid growth over the past decade because of their affordable, simple and portable properties [ 24 , 25 ]. Due to the sustainability and superior mechanical properties of cellulose, the µPADs possess the capillary-driven fluid flow, allowing the sample and the reagent to flow through the hydrophilic fibrous area within the device without the requirement of external instruments [ 26 , 27 ]. With this aspect, the µPADs have been developed in several patterns and in different types of platforms depending on their applications such as the storage of liquid reagents [ 28 , 29 ], the stop flow devices [30] and the channels for sample pretreatment [31] .…”