Microfluidic chip-capillary electrophoresis with adjustable on-chip sample dilution for profiling of urinary markers

Abstract

The paper reports the development of a microfluidic chip-capillary electrophoresis device using UV/Vis detection for profiling of urinary markers with adjustable on-chip sample dilution. A PMMA polymer microfluidic chip-CE device with on-chip ferrofluid valve control for adjustable sample dilution is developed for profiling of urinary markers related to metabolism disorders for clinical diagnosis. On-chip sample dilution up to a 100 folds can be achieved prior to separation in a running buffer containing 3mM 1,3,5-benzenetricarboxylic acid (BTA), 1.5 mM tetraethylenepentamine (TEPA) and 15mM tris(hydroxyl) aminomethane (Tris buffer) solution with pH adjusted to 8.4 by lithium hydroxide.