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Updated: Jan 23, 2026

Detection and Monitoring of Tumor Associated Circulating DNA in Patient Biofluids
Published on: June 8, 2019
Coaxial sensing bio-amplifier for ultrasensitive detections of circulating tumor DNAs
Zhen Zhang1, Mengting Zhu2, Zichao Chen1
1Shandong Province Key Laboratory of Detection Technology for Tumor Markers, College of Chemistry and Chemical Engineering, Linyi University, Linyi, 276000, PR China.
Abstract:
We herein report the first attempt to engineer a coaxial-sensing 3D amplifier able to achieve dynamic self-assembly in response to a mutated-ctDNA target. A bio-nanofiber is firstly manufactured via an ingenious double-channel electrostatic spinning and DNA rolling circle replication (RCR) technology, which offered an ideal scaffold for assembly of 3D amplifier activated by target recognition. The coaxial-controllable signal amplifier presented several advantages. (1) Given its "coaxial sensing effect", the proposed bio-amplifier played the coaxial transduction for signal enrichment to vastly increase sensitivity, capable of discriminating a single-base mismatched sequence from the perfectly complementary one, using ctDNA-134A as a model analyte. (2) Due to "covalent bridges lock effect" in an identifying chip with locked nucleic acid beacons, this 3D amplifier expressed high specificity and biostability toward seven different mutated-ctDNAs. (3) Profiting from special configuration of bioactive nanofibers and DNA replication programming, this catalytic bio-amplifier possessed "signal enrichment effect", which enhanced dynamic range toward ctDNA-134A detection and hybridized without any external indicators. This innovative bio-amplifier has a detection limit of 5.1 aM for ctDNA-134A with superior specificity, excellent sensitivity, and good performance. This pioneered method was further applied for broadly differentiate cells and evaluate changes in the expression levels of intracellular mutated-ctDNAs.
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