A microchip electrophoresis-assisted triple-cycle cascade chemiluminescence signal amplification strategy for the ultrasensitive detection of microRNA-141 in cells

Based on the microchip electrophoresis chemiluminescence detection (MCE-CL) platform, an ultrasensitive method was developed for the detection of microRNA-141 (miRNA-141) by using T7 exonuclease (T7 Exo)assisted triple-cycle cascade chemiluminescence signal amplification strategy. In this method, the horseradish peroxidase (HRP)-labeled single strand DNA (HRP-DNA) was used as a signal probe for the cascade signal amplification identification of miRNA-141 in cancer cells. Under the optimized experimental conditions, the chemiluminescence intensity and logarithm of the miRNA-141 concentration showed a good linear relationship. The detection limit for miRNA-141 assay reached 9.1 x 10-17 M (S/N = 3). This method displayed excellent specificity for differentiating miRNAs with base mismatch, and was applied to determine miRNA-141 in the lysates of cancer cells. This method shows important applications when using limited amounts of biological samples for clinical diagnostics and biomedical research of miRNAs.

Automated summary

Based on the microchip electrophoresis chemiluminescence detection platform, an ultrasensitive method was developed for the detection of microRNA-141 by using a triple-cycle cascade chemiluminescence signal amplification strategy. This method showed excellent specificity and a very low detection limit for miRNA-141 assay. It has important applications in clinical diagnostics and biomedical research of miRNAs.