Thread based electrofluidic platform for direct metabolite analysis in complex samples.

Area of Science:

• Analytical Chemistry
• Biomaterials Science

Background:

• Developing low-cost, accessible diagnostic assays is crucial for point-of-care testing.
• Traditional electrophoresis methods can be complex and expensive, limiting widespread application.
• Metabolite quantification in complex biological matrices like urine requires sensitive and selective separation techniques.

Purpose of the Study:

• To investigate the use of commercial threads as a platform for electrophoresis-based diagnostics.
• To develop a low-cost, rapid assay for the separation and quantification of low-abundance metabolites, specifically riboflavin in human urine.

Main Methods:

• Evaluation of eight commercially available threads for zone electrophoresis, assessing electroosmotic flow (EOF) and electrophoretic mobility.
• Selection of a nylon thread bundle based on performance metrics like band dispersion, resolution, EOF, and joule heating.
• Design and implementation of a novel 3D-printed modular platform to facilitate electrophoresis and enable multiplexing.

Main Results:

• Several synthetic threads showed higher EOF and improved mobility for model compounds (rhodamine 6G, B, fluorescein).
• The selected nylon thread platform demonstrated reduced band dispersion, higher resolution, and a significant relative EOF.
• The thread-based electrophoresis system successfully quantified riboflavin in human urine within 2 minutes, with a linear working range of 0.1–15 μg/mL.

Conclusions:

• Commercial threads, particularly nylon, offer a viable and cost-effective platform for electrophoresis-based diagnostic assays.
• The developed 3D-printed modular system enhances usability and holds potential for multiplexed and complex analyses.
• This thread-based electrophoresis method provides a rapid and accurate approach for riboflavin determination in urine, comparable to capillary electrophoresis.