Electrochemiluminescence Analysis of Multiple Glycans on Single Living Cell with a Closed Bipolar Electrode Array Chip

Abstract

The profiling of multiple glycans on a single cell is important for elucidating glycosylation mechanisms and accurately identifying disease states. Herein, we developed a closed bipolar electrode (BPE) array chip for live single-cell trapping and in situ galactose and sialic acid detection with the electrochemiluminescence (ECL) method. Methylene blue-DNA (MB-DNA) as well as biotin-DNA (Bio-DNA) codecorated AuNPs were prepared as nanoprobes, which were selectively labeled on the cell surface through chemoselective labeling techniques. The individual cell was captured and labeled in the microtrap of the cathodic chamber, under an appropriate potential, MB molecules on the cellular membrane underwent oxidation, triggering the reduction of [Ru(bpy) 3 ] 2+ /TPA and consequently generating ECL signals in the anodic chamber. The abundance of MB groups on the single cell enabled selective monitoring of both sialic acid and galactosyl groups with high sensitivity using ECL. The sialic acid and galactosyl content per HepG2 cell were detected to be 0.66 and 0.82 fmol, respectively. Through comprehensive evaluation of these two types of glycans on a single cell, tumor cells, and normal cells could be effectively discriminated and the accuracy of single-cell heterogeneous analysis was improved. Additionally, dynamic monitoring of variations in galactosyl groups on the surface of the single cell was also achieved. This work introduced a straightforward and convenient approach for heterogeneity analysis among single cells.

Numerical Simulation of the Influence of Non-Uniform ζ Potential on Interfacial Flow

“…Due to the widespread existence of interfacial phenomena [ 1 , 2 , 3 , 4 , 5 ], EDL and its dynamics play important roles in many fields, such as microfluidic technology [ 6 , 7 , 8 ], electrochemical analysis [ 9 ], energy systems [ 10 , 11 ], and biomedical applications (e.g., pharmaceutical analysis [ 12 ] and cell detection [ 13 ]). Relying on the electric properties of EDL, the electrokinetic (EK) flow (like electroosmotic flow) under the action of electric field have been broadly applied, to control flow [ 14 ], deliver drugs [ 15 ], enhance mixing in micro-/nanofluidic devices [ 16 , 17 ], etc.…”