Thread based electrofluidic platform for direct metabolite analysis in complex samples

Abstract

The application of electrophoresis upon commercial threads is investigated for development of low-cost diagnostics assays, designed for the matrix separation and quantification of low abundance metabolites in complex samples - in this work riboflavin in human urine. Zone electrophoresis was evaluated upon 8 commercially available threads, with several synthetic threads exhibiting higher electroosmotic flow (EOF) and increased electrophoretic mobility of the rhodamine 6G, rhodamine B, and fluorescein. Of those tested, a nylon bundle was selected as the best platform, offering less band dispersion and higher resolution, a high relative EOF, whilst minimising the contribution of joule heating. A novel 3D printed platform was designed, based on a modular system, facilitating the electrophoresis process and rapid assembly, whilst offering the potential for multiplexed analysis or investigation of more complex systems. Using the thread-based electrophoresis system, riboflavin was determined in less than 2 min. The device exhibited a linear working range from 0.1 to 15 μg/mL of riboflavin in urine, and was in good agreement with capillary electrophoresis measurements.

Electrofluidic control of bioactive molecule delivery into soft tissue models based on gelatin methacryloyl hydrogels using threads and surgical sutures

“…When external electric field was applied, the electrokinetic phenomenon of electrophoresis was observed and ultimately caused the presence of a charged interface on the surface and the consequent migration of molecules. Electrofluidic dynamics depend mostly on the physicochemical properties of the thread, the physical properties of the hydrogel, and the composition of the electrolyte/buffer used 9,12 . Thread resistance (referred to the buffer suspended in the thread) changes with the thread diameter, length and wettability (material hydrophilicity), whereas hydrogel electrical resistance depends on gel dimensions, structure of crosslinked networks and water content (Fig.…”

“…bioanalysis [8][9][10][11][12][13][14] , and embedded in a hydrogel as a network for chemotaxis studies 15 or multilayer feeding of cell cultures 16 . This capillary action subsequently drives the fluid along the thread, and it is directly related to the material hydrophilicity on the surface.…”

Thread/Cord-Based Microfluidic Devices in Modern Analysis

“…Cotton threads are light, hydrophilic, and flexible and do not require any patterning of hydrophobic barriers to restrict liquids within channels. Also, cotton never becomes brittle when wetted by liquids, which is of a different quality from paper [20][21][22][23][24]. Thread has various advantages that make it appropriate to be useful in microfluidicsbased technologies which include its low price, its lightweight, its easy availability, and its hydrophilic nature.…”

Thread integrated smart-phone imaging facilitates early turning point colorimetric assay for microbes

“…[25][26][27][28] In recent years there has been growing interest in using mTADs for numerous assays, 9 including enzyme-linked immune-sorbent assay (ELISA) for detecting antibodies, 29 immuno-chromatographic assays, 30,31 glucose assays [32][33][34] and other applications. [34][35][36][37][38][39][40][41][42][43][44] Furthermore, literature reveals that the utilization of TADs for colorimetric assays, with simple thread acting as a medium for holding test reagents and the white color of it providing a perfect background for colorimetric signal development and processing. 25,[45][46][47] In addition, smartphones have also been employed for image analysis of threadbased colorimetric assays.…”