Related Experiment Video
Updated: Feb 15, 2026

Low Molecular Weight Protein Enrichment on Mesoporous Silica Thin Films for Biomarker Discovery
Published on: April 17, 2012
Sensitive electrochemical detection of microRNA-21 based on propylamine-functionalized mesoporous silica with
Kun Deng1, Yong Zhang2, Xuedong Tong2
1Department of Clinical Laboratory, The Third Affiliated Hospital, Chongqing Medical University, Chongqing, 401120, China. dr_dengkun@yeah.net.
Abstract:
A new homogeneous electrochemical sensing system was developed for sensitive detection of microRNA-21 (miRNA-21) based on target-induced glucose release from propylamine-functionalized mesoporous silica nanoparticle (MSN) with glucometer readout. Glucose molecules (as the signal tracers) were initially gated into the pores through the interaction of the negatively charged anchor DNA with the aminated MSN. Upon addition of target miRNA, the analyte competitively hybridized with anchor DNA to form the RNA-DNA duplex, thus resulting in detachment of anchor DNA from the MSN accompanying the pore opening. The loaded glucose molecules released out from the pores because of concentration gradients, which could be detected by using a portable personal glucometer (PGM). Experimental results indicated that the PGM signal increased with the increasing miRNA level, and exhibited a good linear dependence on the miRNA-21 concentration from 50 pM to 5.0 nM with a detection limit of 19 pM under optimum conditions. Additionally, multifunctional mesoporous silica nanoparticles also showed good stability and favorable selectivity, and satisfactory accuracy for the miRNA detection in cell lysates with quantitative real-time polymerase chain reaction (qRT-PCR). Such good analytical performance endows it as a promising scheme for the efficient and convenient detection of miRNA in clinical diagnosis and therapy. Graphical abstract An electrochemical sensing system is designed for detection of microRNA-21 based on target-induced glucose release from propylamine-functionalized mesoporous silica nanoparticle with glucometer readout.
Related Concept Videos
MicroRNAs
MicroRNAs
What is an Electrochemical Gradient?
The chemical gradient relies on differences in the abundance of a substance on the outside versus the inside of a cell and flows from areas of high to low ion concentration. In contrast, the electrical gradient revolves around an...
Exponential Functions with Base e
Silica Gel Column Chromatography: Overview
Polar components tend to bind strongly to the silica gel, causing them to move slowly through the column. In contrast, nonpolar compounds...
Interfacial Electrochemical Methods: Overview

