A General Signal Amplifier of Self-Assembled DNA Micelles for Sensitive Quantification of Biomarkers

Abstract

Owing to the excellent structural rigidity and programmable reaction sites, DNA nanostructures are more and more widely used, but they are limited by high cost, strict sequence requirements, and time-consuming preparation. Herein, a general signal amplifier based on a micelle-supported entropy-driven circuit (MEDC) was designed and prepared for sensitive quantification of biomarkers. By modifying a hydrophobic cholesterol molecule onto a hydrophilic DNA strand, the amphiphilic DNA strand was first prepared and then self-assembled into DNA micelles (DMs) driven by hydrophobic effects. The as-developed DM showed unique advantages of sequence-independence, easy preparation, and low cost. Subsequently, amplifier units DMF and DMTD were successfully fabricated by connecting fuel strands and three-strand duplexes (TDs) to DMs, respectively. Finally, the MEDC was triggered by microRNA-155 (miR-155), which herein acted as a model analyte, resulting in dynamic self-assembly of poly-DNA micelles (PDMs) and causing the recovery of cyanine 3 (Cy3) fluorescence as the DMTD dissociated. Benefiting from the “diffusion effect”, the MEDC herein had a nearly 2.9-fold increase in sensitivity and a nearly 97-fold reduction in detection limit compared to conventional EDC. This amplifier exhibited excellent sensitivity of microRNAs, such as miR-155 detection in a dynamic range from 0.05 to 4 nM with a detection limit of 3.1 pM, and demonstrated outstanding selectivity with the distinguishing ability of a single-base mismatched sequence of microRNAs. Overall, the proposed strategy demonstrated that this sequence-independent DNA nanostructure improved the performance of traditional DNA probes and provided a versatile method for the development of DNA nanotechnology in biosensing.

Unraveling the Possibilities: Recent Progress in DNA Biosensing

“…This structure enhances the resistance to nuclease degradation, and the high-density nucleic acids on the surface also improve reaction rates [ 123 , 124 ]. There are also studies using carbon nanotubes [ 125 ], graphene [ 126 ], upconversion materials [ 127 , 128 ], or micelles [ 129 , 130 ] to engineer DNA nanostructures. This strategic incorporation of materials with diverse properties has greatly broadened the application scenarios of DNA sensing.…”

DNA Nanospheres Assisted Spatial Confinement Signal Amplification for MicroRNA Imaging in Live Cancer Cells

“…DNA assemblies are commonly used in biosensing, particularly for microRNA (miRNA). MiRNA is an endogenous noncoding small RNA, approximately 19–23 nucleotides long, which plays a crucial role in cell growth regulation. , DNA assemblies with enzyme-free signal amplification, such as catalytic hairpin assembly (CHA), , hybridization chain reaction (HCR), , entropy-driven circuit (EDC), , and DNA artificial enzyme (DNAzyme), , have been developed to address the limited and scarce presence of miRNA. The Kong group reported a DNA nanolantern, which could be easily integrated with the HCR to realize the multisignal output of a single-molecule target .…”

Multiple miRNA Detection through a Suspended Microbead Array Encoded by Triple-Color Upconversion Luminescent Nanotags via Bi-Beam Splitter Hybrid-Multitrap Optical Tweezers

“…MiR-342-3p related to BRCA 1 expression and miR-155 playing a key role in inducing angiogenesis and tumor growth in breast tumors are upregulated by a large margin in TNBC, , while miR-199a-5p has a tumor-suppressive effect and shows lower expression in TNBC . There have been relevant reports on the detection of the three kinds of target miRNAs for indicating TNBC. − …”