Predicting Dimensions in Microfluidic Paper Based Analytical Devices

Abstract

The main problem for the expansion of the use of microfluidic paper-based analytical devices and, thus, their mass production is their inherent lack of fluid flow control due to its uncontrolled fabrication protocols. To address this issue, the first step is the generation of uniform and reliable microfluidic channels. The most common paper microfluidic fabrication method is wax printing, which consists of two parts, printing and heating, where heating is a critical step for the fabrication of reproducible device dimensions. In order to bring paper-based devices to success, it is essential to optimize the fabrication process in order to always get a reproducible device. Therefore, the optimization of the heating process and the analysis of the parameters that could affect the final dimensions of the device, such as its shape, the width of the wax barrier and the internal area of the device, were performed. Moreover, we present a method to predict reproducible devices with controlled working areas in a simple manner.

Spatial and temporal detection of root exudates with a paper-based microfluidic device

“…In this study, we propose the development of a paper-based microfluidic device to extract root exudates from precise locations along the root at regular time intervals. In order to do that, wax patterns were printed using commercial a printer (Carrilho et al, 2009; Lind et al, 2021) to create well defined fluidic channels able to direct the flow of liquid with the exudates though the paper (Potter et al, 2019; Catalan-Carrio et al, 2021). We used the technique to print vertical channels that transport exudates towards a TiO 2 nanotubes (TNT)/alginate hydrogel-based glucose sensor polymerised at the outlet of the paper channel (Gunatilake et al, 2021).…”

A Parametric Study on a Paper-Based Bi-Material Cantilever Valve

“…Although they generally offer users more temporal control, active flow control techniques are more difficult to build and generally necessitate the use of external instruments [23][24][25]. Passive approaches, on the other hand, often require the users to modify the system's physical [12] and/or chemical features [26], such as the size of the transport channel [27], the viscosity of the fluid [28], or the hydrophilicity and wettability of the transport channel [29]. In our previous publications, we described a novel autonomously activated paper-based cantilever (PBC) [30] and the bi-material cantilever (B-MaC) [31,32] that offer several unique advantages for use in paper-based microfluidic devices.…”