Electrochemical Cellulase-Linked ELASA for Rapid Liquid Biopsy Testing of Serum HER-2/neu

Ana Díaz-Fernández, Alexey Ferapontov, Mikkel Holm Vendelbo, Elena E. Ferapontova*

*Corresponding author for this work

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

9 Citations (Scopus)

Abstract

Non-invasive liquid biopsy assays for blood-circulating biomarkers of cancer allow both its early diagnosis and treatment monitoring. Here, we assessed serum levels of protein HER-2/neu, overexpressed in a number of aggressive cancers, by the cellulase-linked sandwich bioassay on magnetic beads. Instead of traditional antibodies we used inexpensive reporter and capture aptamer sequences, transforming the enzyme-linked immuno-sorbent assay (ELISA) into an enzyme-linked aptamer-sorbent assay (ELASA). The reporter aptamer was conjugated to cellulase, whose digestion of nitrocellulose film electrodes resulted in the electrochemical signal change. ELASA, optimized relative aptamer lengths (dimer vs monomer and trimer), and assay steps allowed 0.1 fM detection of HER-2/neu in the 10% human serum in 1.3 h. Urokinase plasminogen activator and thrombin as well as human serum albumin did not interfere, and liquid biopsy analysis of serum HER-2/neu was similarly robust but 4 times faster and 300 times cheaper than both electrochemical and optical ELISA. Simplicity and low cost of cellulase-linked ELASA makes it a perspective diagnostic tool for fast and accurate liquid biopsy detection of HER-2/neu and of other proteins for which aptamers are available.

Original languageEnglish
JournalACS Measurement Science Au
Volume3
Issue3
Pages (from-to)226-235
Number of pages10
DOIs
Publication statusPublished - Jun 2023

Keywords

  • antibody
  • aptamer
  • cellulase
  • electrochemical enzyme-linked aptamer-sorbent assay (ELASA)
  • electrochemical sandwich assay
  • HER-2/neu
  • magnetic beads

Fingerprint

Dive into the research topics of 'Electrochemical Cellulase-Linked ELASA for Rapid Liquid Biopsy Testing of Serum HER-2/neu'. Together they form a unique fingerprint.

Cite this