A Photoresponsive and Metal–Organic Framework Encapsulated DNA Tetrahedral Entropy-Driven Amplifier for High-Performance Imaging Intracellular MicroRNA

Abstract

The further development of high-performance fluorescent biosensors to image intracellular microRNAs is beneficial to cancer medicine. By virtue of the need for enzymes and hairpin DNA probes, the entropy-driven reaction-assisted signal amplification strategy has shown an enormous potential to accomplish this task. Nevertheless, this good option still meets with poor biostability, low cell uptake efficiency, and unsatisfactory accuracy. On the basis of these challenges, we put forward here a battery of solving pathways. First, the straight DNA probes are anchored onto the vertexes of dual DNA tetrahedrons, and thus the enzyme resistance of the whole sensing system is observably enhanced. A metal−organic framework (ZIF-8 nanoparticle), which can be effectively dissociated into a weakly acidic environment, then is employed as an additional delivery vehicle to encapsulate such a DNA tetrahedron sustained biosensor and finally bring about a more efficient endocytosis. Last, a kind of photocleavage-linker triggered photoresponsive manner is incorporated to achieve an exceptional precise target identification, by which the biosensor can only be initiated under the irradiation of an externally mild 365 nm ultraviolet light source. In accordance with the above efforts, worthy assay performance toward microRNA-196a has given rise to this newly constructed biosensor, whose sensitivity is down to 2.7 pM and also able to distinguish single-base variation. Beyond that, the amplifier can work as a powerful imaging toolbox to accurately determine the targets in living cells, providing a promising intracellular sensing platform.

Antioxidant Cascade Nanoenzyme Antagonize Inflammatory Pain by Modulating MAPK/p‐65 Signaling Pathway

“…[ 13 ] Importantly, ZIF‐8 NPs could encapsulate a variety of biological macromolecules, such as proteins (enzymes) and DNA, through a simple, low‐cost biomimetic mineralization process preventing their leakage and maintaining their biological activity. [ 14 ] Notably, ZIF‐8 NPs decompose easily under acidic conditions (pH 5–6), which is conducive to efficiently delivering and releasing composite materials in a weakly acidic inflammatory environment. [ 15 ] All these suggest that ZIF‐8 NPs are an excellent candidate for constructing multienzyme catalytic platforms; however, it has seldom been exploited for synergistic pain relief applications.…”

NIR Photocontrolled Fluorescent Nanosensor under a Six-Branched DNA Nanowheel-Induced Nucleic Acid Confinement Effect for High-Performance Bioimaging

“…As a result, seeking an effective means to confine the reactants into a restrictive contact space is another difficulty. With the rapid extension of ingenious DNA nanostructures, a concept named nucleic acid confinement effect is capable of being utilized to intensively accelerate the intermolecular mass transportation efficiency. − Among the available structure types (e.g., cage, tetrahedron, triangular prism, and wheel), the wheel case containing multiple DNA branches has not only the advantage of loading abundant fluorescence output units but also a more flexible construction.…”

Light-Driven and Metal–Organic Framework Synergetic Loaded DNA Tetrahedral Amplifier for Exonuclease III-Powered All-in-One Biosensing and Chemotherapy in Live Biosystems

“…As a result of these lost fluorescence signals, the concentration corresponding to the location where the DNA amplifiers arrive is unlikely to represent reality, and this inaccurate biosensing has limited therapeutic applications. However, there has been significant development in biosensing modes, and the light-driven concept shows promise for resolving this issue. − As a rule, a simple O -nitrobenzyl-composed photocleavage-linker (PC-linker) can be embedded into the analyte identification component. Subsequently, irradiation with 365 nm ultraviolet (UV) light induces the exposure of the target binding domain with control over the spatiotemporal behavior, thus resulting in more precise biosensing information.…”