Polymer Components for Paper‐Based Analytical Devices

Abstract

In recent years, paper has become an essential substrate material for developing different types of sensors, from wearable devices to single‐use test strips and biosensors. In parallel, a polymer‐based toolbox has emerged in order to add additional functions to these paper‐based analytical devices. In this article, examples are compiled from the recent literature showing microfluidic systems based on printing impermeable polymer barriers with different methods as well as the implementation of electrochemical, fluorescent, and colorimetric polymer‐based transducers in paper‐based analytical platforms. Externally actuated or dissolvable polymer valves and reservoirs, analyte concentrators, and separation devices, as well as polymer‐based recognition elements (molecularly imprinted polymers) printed on paper substrates are also reviewed. The search has revealed a plethora of possibilities for developing complex lab‐on‐chip devices implementing different polymer‐based components in them. The ability of patterning these polymers with common printing methods that do not require specialized facilities paves the way for mass producing this kind of advanced paper‐based analytical device.

Engineering a Point-of-Care Paper-Microfluidic Electrochemical Device Applied to the Multiplexed Quantitative Detection of Biomarkers in Sputum

“…As a disposable component, this paper enables the sequential additions of the MNPs dispersion upon sample pretreatment, washing steps, and measuring solution to be performed without the need for any external mechanical components. Among the different paper patterning approaches that have been reported, 42 wax printing has been widely applied to the simple parallel fabrication of a variety of features. 43 This technique involves a three-step method that includes pattern drawing, paper printing using a commercial wax printer, and a thermal step carried out at a low temperature using an oven or a hot plate to allow impregnation of the wax across the paper to reach the back-paper side.…”

“…The further incorporation of all of the required reagents in the paper component while working on device storage stability and achieving an ideal sample-in answer-out performance is being addressed. Lyophilization reagent procedures could aid in the incorporation of the different biocomponents, while the integration of some simple actuating structures on the paper component may allow for the sequential performance of the required assay steps in a semi-automatic fashion . This might bring the presented technology closer to the so-called target product profiles defined for different analytical platforms applied in the diagnostic of diseases under specific conditions of use …”