Membrane-anchored DNA nanodevice with allosteric aptamer arms enables parallel probing and on-site drug delivery

A Light-Controlled DNA Nanoclaw Machine: Integrated Multiplexed Recognition, Spatiotemporally Programmable Therapy, and Real-Time Electrochemical Signaling for Precision Receptor Regulation

Cell membrane receptors are pivotal targets in precise therapeutics, yet their ubiquitous expression across tissues remains a fundamental barrier to achieving cell-specific intervention. To overcome the limitations of conventional monotargeting approaches, we developed a light-gated DNA nanoclaw machine (L-DNM) that integrates high-specificity recognition, spatiotemporally controlled therapy, and real-time monitoring of molecular activation within a unified nanoplatform. The L-DNM employed a multivalent targeting mechanism directed against a triple-marker signature, epithelial cell adhesion molecule (EpCAM), MUC1, and nucleolin (NCL), achieving exceptional targeting accuracy toward MCF-7 human breast cancer cells even in heterogeneous environments. Its novel photocleavable aptamer design ensures that the Met-inhibiting function remains biologically inert until activated by UV irradiation. This strategy enables precise spatiotemporal control over receptor tyrosine kinase (RTK) inhibition with minimal off-target effects. Furthermore, the system couples therapeutic activation with instantaneous electrochemiluminescence (ECL) reporting, transforming molecular recognition events into quantifiable signals with high signal-to-noise ratio in complex matrices. By unifying multiplexed targeting, light-gated activation, and self-reporting capability, the L-DNM platform represents a transformative shift from conventional therapeutics to adaptive, intelligent theranostic systems.

Co-Localization-Gated Multivalent DNA Logic Gate for Programmable Cell Recognition.

Achieving precise and robust cell-surface recognition in complex biological environments is challenging due to inherent trade-offs in affinity, specificity, and off-target binding. Herein, we present a programmable molecular device that integrates Boolean logic computation with spatial confinement to overcome these limitations. Our system employs valence-controllable, split DNAzyme modules assembled on a tetrahedral DNA nanostructure (TDN). The peroxidase-mimicking activity is stringently gated by a cell-surface AND logic, requiring the co-localization of two adjacent modules on target protein clusters for activation. This spatial constraint effectively eliminates stochastic or unintended signal leakage originating from solution-phase reactions or nontarget cells. Upon activation, the DNAzyme catalyzes the biotinylation of neighboring membrane protein clusters, generating stable multivalent adhesion sites. Quantitative dissociation kinetics reveal that the trivalent design of the DNAzyme modules promotes highly cooperative binding, resulting in uniform, long-lived complexes on target cells. We demonstrate that this approach enables specific recognition and highly efficient isolation of target cells from mixed cell populations and clinical samples, showcasing a strategy for programming high-fidelity molecular interactions on interested cell surfaces.

A dual-recognition fluorescence chip utilizing a substrate-borne DNA walker for precision profiling of small extracellular vesicles.

We report a fluorescence chip based on a membrane-anchored, bipedal DNAzyme walker assembled on small extracellular vesicles (sEVs) surfaces via catalytic hairpin assembly (CHA). Unlike previously reported single-arm or proximity-ligation-dependent walkers on nanoparticle supports, this CHA-triggered DNAzyme walker is designed with a bipedal architecture and operates directly on the sEVs membrane. In our design, CHA simultaneously generates two DNAzyme arms on the same sEVs, enabling faster substrate cleavage kinetics and superior signal amplification. The assay achieves a theoretical detection limit of 2.8 particles/μL, approximately 1.5-fold lower than a comparable single-arm architecture. Dual recognition of the sEVs lipid bilayer and surface EpCAM protein (using a cholesterol-modified substrate and an anti-EpCAM antibody) effectively eliminates false-positive signals from free EpCAM or soluble interferents. The entire reaction cascade is integrated onto a chip platform, improving reproducibility and point-of-care potential. The chip performs robustly in fetal bovine serum and clinical serum samples, with recovery rates of 99.1-103.8% and strong correlation with nanoparticle tracking analysis. By establishing a CHA-assisted, bipedal walking mechanism on biological membranes, this work opens a new paradigm for designing efficient DNA nanomachines on membrane-enveloped targets.

Potentiating In Vivo Precision Cancer Therapy With Modularized Aptamer-Chemotherapeutics Conjugates Based on DNA Tiling-Mediated Structural Nanotechnology.

While DNA origami nanotubes have been often used in the biomedical field, the technical challenges in the assembly at large scale and the susceptibility to degradation limit their exploration for clinical application. In the current contribution, we propose a structural DNA nanotechnology (TMM) for the construction of a degradation-resistant DNA nanotube (DNT) via periodically tiling two structural modules (M) into a modularized (M) tubular DNA nano-architecture. The tube circumference is 118.6 nm, the tube length is 478 nm and the assembly efficiency is almost up to 90%. Upon installation of up-down tumor cell-binding aptamers onto each structural module in a highly precise manner, a protective outer layer was formed. Compared with Biotin-DNA nanowire, the relative nuclease degradation resistance of AS1411-DNT is improved by about 92-fold. Via using commercially synthesized 5-FU-embedded DNA components, we constructed a tumor cell-targeting therapeutic agent-loaded nanoconjugate, AS1411-DNT-5-FU, which exhibits significantly higher therapeutic outcomes than clinic free 5-FU in MCF-7 tumor-bearing mouse models without observable systemic toxicity. While DNA DNT holds great potential for precise drug delivery for cancer therapy, the modularization-based TMM structural DNA nanotechnology is expected to promote the development of next-generation multifunctional 3D-DNA nanostructures and clinical application in precision medicine.

Aptamer Circuit-Engineered Bio-Nanovesicles With Self-Promoted Tumor-Targeting Loop for Efficient Immunogenic Chemotherapy.

Targeted delivery of chemodrugs to tumor sites is highly desirable for efficient chemotherapy. Extracellular vesicles (EVs)-based carrier is an ideal candidate for drug delivery in cancer therapy. However, the insufficient tumor-targeting capability remains to be solved. Herein, we designed an aptamer circuit with cascade recognition capacity to guide the vesicles for tumor targeting. The sequential signal transduction triggered by the specific binding between aptamers and their targets leads to the preferential binding of vesicles with cancerous cells rather than noncancerous cells with fewer targets. Moreover, a self-promoted tumor-targeting loop induced by Doxorubicin Hydrochloride (DOX) released from vesicles further amplified the targeting capability of the vesicle-based drug carrier to tumor sites through up-regulating PDL1 marker on the surface of tumor cells. Ultimately, the accumulation of DOX in tumor cells resulted in the immunogenic cell death (ICD) for evoking anti-tumor immune response. Overall, this work presents a self-promoted tumor-targeting strategy for vesicle-based carrier by coupling the cascade recognition and tumor-targeting loop, which improves the therapeutic effect of immunogenic chemotherapy.

A programmable DNA tetrahedron platform for selective and efficient capture of cells and proteins.