Programming nanoparticle valence bonds with single-stranded DNA encoders

The nucleic acid reactions on the nanomaterials surface for biomedicine

Integrating nucleic acids (NAs) with nanomaterials has substantially advanced biomedical research, enabling critical applications in biosensing, drug delivery, therapeutics, and the synthesis of nanomaterials. At the core of these advances are the reactions of NAs on nanomaterial surfaces, encompassing conjugation (covalent and non-covalent), detachment (physical and chemical), and signal amplification (enzyme-mediated signal amplification, enzyme-free signal amplification, and DNA Walker). Here, we review the fundamental mechanisms and recent progress in nucleic acid reactions on nanomaterial surfaces, discuss emerging applications for diagnostics, nanomedicine, and gene therapy, and explore persistent challenges in the field. We offer a forward-looking perspective on how future developments could better control, optimize, and harness these reactions for transformative advances in nanomedicine and biomedical engineering.

Electron Perturbation for Chiral DNA Point Mutation

Advances in molecular nanotechnology have enabled the design of systems that exploit nanoscale interactions for enhanced biosensing and diagnostics. Here, we present a plasmonic nematic film (PNF) that leverages nanoscale plasmonic hotspots to amplify electron perturbations induced by DNA mutations. Sequence-specific mismatches, particularly point mutations, significantly alter the local electromagnetic environment, leading to distinct and quantifiable spectral shifts in circular dichroism (CD), denoted as Δλdip. These shifts exhibit a strong correlation with target DNA concentration (R2 > 0.99), enabling precise, quantitative detection of mutation-induced asymmetry. The underlying mechanism is modeled by the asymmetric chiral signal Iasy = ∫ΨPNF*(Ω)ΨPNF dV, where ΨPNF is the wave function of the PNF and Ω represents its chiroptical response. Simulations and electric field analysis further validate that mutation-driven perturbations at the PNF-DNA interface enhance local field intensity at λdip, while no significant changes occur at nonresonant wavelengths. Through this mechanism, the PNF platform achieves over 240% enhancement in chiroptical signal compared to wild-type DNA and enables mutation detection down to 1534 pg. These findings highlight the system's potential for high-specificity diagnostics of clinically relevant mutations, including those associated with hereditary hearing impairment, and may inform the development of future chiral biosensing platforms.

Convergence of DNA nanotechnology and polymer chemistry to 'synthesize' nanopolymers with branching architectures: a computational perspective

Polymer-like superstructures termed nanopolymers from the self-assembly of atom-like nanoparticles are an emerging class of structured metamaterials with enhanced functionalities, but the controllable 'synthesis' of nanopolymers with non-linear architecture and spatially defined dimensions remains a challenge. Inspired by synthetic concepts of branched polymers, we propose a hierarchical polymerization-like protocol for the programmable coassembly of DNA-based multicomponent mixtures into non-linear nanopolymers with well-defined branching architecture and predictable spatial dimensions. By employing computational simulations, it is theoretically demonstrated that the synergy of sequence-designed DNA motifs and the proposed protocol enables the precise control over the assembly kinetics of atom-like nanoparticles and the branching architectures of nanopolymers, in agreement with the predictions of the generalized polymerization kinetics model. Furthermore, it is demonstrated that the fundamental correlations between the spatial dimension and branching architecture of nanopolymers satisfy the scaling law acquired in polymer science. These findings will facilitate the programmable coassembly of DNA supramolecules into structured metamaterials with architectural complexity observed in nature.

A cofactor mediated supramolecular oligo-adenine triplex for reprogrammable macroscopic hydrogel assembly

Noncanonical DNA structures mediated by low-molecular-weight cofactors significantly enrich the arsenal of the DNA toolbox and expand its functional applications. In this study, cyanuric acid (CA), a cofactor with three thymine-like edges, is employed to assemble adenine-rich strands (A-strands) into a parallel noncanonical A-CA triplex configuration through Watson-Crick and Hoogsteen interactions. This assembly occurs at a system pH value below the pKa of the CA cofactor (6.9), where CA is protonated, while its deprotonation at higher pH levels leads to the dissociation of the A-CA triplex into single A-strands and free CA cofactors. The structural transition is fully pH reversible. The A-CA triplex is further utilized as a crosslinking element for reprogrammable macroscopic object assembly, exemplified by hydrogel cubes (5 × 5 × 5 mm), a topic that has been less explored compared to nano- and microscopic constructs. Controlled, modular assembly and disassembly of various configurations, such as square, line, and T-shape, are demonstrated through reversible pH adjustments. This strategy offers a streamlined approach using a single DNA sequence and cofactor for hydrogel modification and complex construction, providing cost-effective, recyclable, and stimuli-responsive functionality, which inspires the development of versatile and adaptive supramolecular systems in chemistry and materials science.

Prescribing DNA Origami Barrel-Directed Subtractive Patterning of Nanoparticles for Crystalline Superstructure Assembly

Long-range ordered lattices formed by the directed arrangement of colloidal particles hold significant promise for applications such as photonic crystals, plasmonic metamaterials, and semiconductor electronics. Harnessing regioselective interactions through DNA-mediated assembly is a promising approach to advancing colloidal assembly. Despite efforts to engineer microscale patchy particles using sequence-specific binding properties of DNA, the control of patch formation on nanoscale isotropic spherical nanoparticles remains challenging. We demonstrate a subtractive patterning strategy using barrel-shaped DNA origami (DNA barrel) to selectively block surfaces of DNA-coated gold nanospheres and create regiospecific patches. By designing binding positions and geometric parameters of DNA barrels, we can achieve controlled accessibility to nanosphere surfaces, forming patchy nanoparticles with tunable patch numbers and sizes. This strategy enables the construction of multidimensional superstructures with well-defined stereo relationships, represented by an unprecedented graphane-like bilayered superlattice. Furthermore, we developed a geometrical model that accounts for anisotropic particle bonding and steric hindrance, elucidating the relationship between architectural outcomes and the structural parameters of DNA-barrel-directed patchy nanoparticles, and enabling reverse engineering designs of potential assembly symmetries. This approach opens new avenues for generating nanoparticle assemblies with distinct symmetries and properties.

Molecular-Cellular Two-Pronged Reprogramming of Inflammatory Soft-Tissue Interface with an Immunosuppressive Pure DNA Hydrogel

Effective modulation of persistent inflammation is crucial for chronic wound healing. However, the interaction cascade between inflammatory factors and immune cells at the soft-tissue wound interface poses an incredible challenge for this purpose. Here, we report an immunosuppressive pure DNA hydrogel (Is-pDNAgel) that reprograms inflammatory responses from both molecular and cellular dimensions. Specifically, high-density negative charges enable Is-pDNAgel to efficiently scavenge free chemokines, mitigating neutrophil and macrophage infiltration. Moreover, its immunosuppressive domain synergistically acts on activated residual immune cells and suppresses multiple proinflammatory signaling pathways, thereby creating a positive circuit to boost anti-inflammatory efficacy. Is-pDNAgel can further facilitate migration and proliferation of endogenous endothelial cells owing to its intrinsic extracellular matrix-mimicking structure, promoting re-epithelialization and neovascularization for tissue regeneration without additional bioactive components. Such an "all-in-one" hydrogel outperforms a commercial dressing to accelerate the healing of chronic wounds in a diabetic mouse model, offering a valuable tool for developing regenerative medicine.

DNA-Guided Self-Assembly of Carbon Nanotubes and Quantum Dots

The ability to robustly and with scalability detect single photons in the visible spectrum with wavelength resolution would transform many imaging applications. Theoretical studies propose an array of carbon nanotubes (CNTs) functionalized with semiconductor quantum dots (QDs) as a physical realization of such photon sensors. In this work, we report approaches to synthesize these CNT-QD nanostructures using DNA as a smart glue to connect CNTs to QDs.

Directional Self-Assembly of Programmable Atom-like Nanoparticles into Colloidal Molecules

Colloidal molecules, novel nanoparticle clusters with molecular-like structures, can enhance material performance and broaden applications in nanotechnology and materials science. However, constructing them with a precise, controllable architecture remains challenging. Inspired by the concepts of chemical reaction, we theoretically design a novel type of nanoparticles bifunctionalized by DNA strands and polymer chains and propose a stepwise strategy to hierarchically program the assembly of bifunctionalized nanoparticles into well-defined colloidal molecules by virtue of coarse-grained molecular dynamics simulations. This method leverages the synergistic effects of polymers and DNA to create programmable atom-like nanoparticles with various valence domains. By carefully designing strands, these nanoparticles are programmed to coassemble into various colloidal molecules with distinct symmetries and coordination numbers, which can be finely tuned by the molecular design of nanoparticles as well as the composition design of the coassembly system. Our strategy provides a novel protocol for the controlled coassembly of nanoparticles into customized colloidal molecules, expanding nanomaterial manufacturing techniques.

Recent advances in nucleic acid-functionalized metallic nanoparticles

Nucleic acid-functionalized metallic nanoparticles (N-MNPs) precisely integrate the advantageous characteristics of nucleic acids and metallic nanomaterials, offering various abilities such as resistance to enzymatic degradation, penetration of physiological barriers, controllable mobility, biomolecular recognition, programmable self-assembly, and dynamic structure-function transformation. These properties demonstrate significant potential in the field of biomedical diagnostics and therapeutics. In this review, we examine recent advancements in the construction and theranostic applications of N-MNPs. We briefly summarize the methodologies employed in the conjugation of nucleic acids with metallic nanoparticles and the formation of their superstructural assemblies. We highlight recent representative applications of N-MNPs in biomolecular diagnosis, imaging, and smart delivery of theranostic agents. We also discuss challenges currently faced in this field and provide an outlook on future development directions and application prospects.

DNA‑Directed Assembly of Photonic Nanomaterials for Diagnostic and Therapeutic Applications

DNA-directed assembly has emerged as a versatile and powerful approach for constructing complex structured materials. By leveraging the programmability of DNA nanotechnology, highly organized photonic systems can be developed to optimize light-matter interactions for improved diagnostics and therapeutic outcomes. These systems enable precise spatial arrangement of photonic components, minimizing material usage, and simplifying fabrication processes. DNA nanostructures, such as DNA origami, provide a robust platform for building multifunctional photonic devices with tailored optical properties. This review highlights recent progress in DNA-directed assembly of photonic nanomaterials, focusing on their applications in diagnostics and therapeutics. It provides an overview of the latest advancements in the field, discussing the principles of DNA-directed assembly, strategies for functionalizing photonic building blocks, innovations in assembly design, and the resulting optical effects that drive these developments. The review also explores how these photonic architectures contribute to diagnostic and therapeutic applications, emphasizing their potential to create efficient and effective photonic systems tailored to specific healthcare needs.

Molecular Circuit-Controlled Nanoparticle Folders for Programmable DNA Information Access

DNA storage has become an attractive alternative to long-term, stable digital data storage because of its high storage density and strong stability. Recently, numerous efforts have been made to develop DNA data access methods to improve the efficiency and accuracy of molecular data reading. However, most current data access methods were achieved by well-developed polymerase chain reaction (PCR) and DNA hybridization, which lack the exploration of dynamic and programmable operations for data access. Here, we propose a programmable DNA data access strategy in which the nanoparticle folders are controlled by DNAzyme circuits to achieve specific information manipulation. We experimentally demonstrate three kinds of circuit programs that access specific information in YES, AND, and OR logic manner. In addition, the selective information access was performed by using a DNAzyme circuit to obtain the target information from a DNA data pool. Importantly, we have extended the circuit-controlled framework to multiple manipulation modes, demonstrating four manipulations on two AuNP folders to access different information on demand. The programmable access strategy provides a paradigm for integrated DNA computing and storage systems and has more applications in the fields of molecular computation and DNA data storage.

Rapid Genotyping of FecB Mutation in Sheep Using CRISPR-Cas12a Integrated with DNA Nanotree Biosensing Platform

The A-to-G mutation (FecB) in the BMPR1B gene is strongly linked to fertility in sheep, significantly increasing ovulation rates and litter sizes compared to wild-type populations. The rapid and reliable screening of the FecB gene is therefore critical for advancing sheep breeding programs. This study aimed to develop a fast and accurate method for detecting the FecB mutation and genotyping the gene to enhance sheep reproduction and productivity. To achieve this, we integrated the CRISPR-Cas12a system with an optimized amplification refractory mutation system (ARMS). A similar DNA origami technique-based fluorescence reporter nanotree structure was synthesized using gold nanomagnetic beads as carriers to amplify the fluorescence signal further. The resulting biosensing platform, termed CRISPR-ARMS, demonstrated excellent sensitivity for detecting FecB mutations, with a detection limit as low as 0.02 pmol. Therefore, this innovative approach shows great promise for single-base mutation detection and represents a pioneering tool for high-yield genetic screening.

Advanced Synthesis of Spherical Nucleic Acids: A Limit-Pursuing Game with Broad Implications

Spherical nucleic acids (SNAs) consist of DNA strands arranged radially and packed densely on the surface of nanoparticles. Due to their unique properties, which are not found in naturally occurring linear or circular DNA, SNAs have gained widespread attention in fields such as sensing, nanomedicine, and colloidal assembly. The rapidly evolving applications of SNAs have driven a modernization of their syntheses to meet different needs. Recently, several advanced approaches have emerged, enabling ultrafast, quantitative, and low-cost SNA synthesis with maximal DNA grafting through "counterintuitive" processes like freezing and dehydration. This concept paper discusses these critical developments from a synthetic perspective, focusing on their underlying mechanisms and broad implications, with a goal of inspiring future research in related fields.

Advances, Challenges, and Opportunities in Plasmonic Nanogap-Enhanced Raman Scattering with Nanoparticles

Surface-enhanced Raman scattering has been widely used for molecular/material characterization and chemical and biological sensing and imaging applications. In particular, plasmonic nanogap-enhanced Raman scattering (NERS) is based on the highly localized electric field formed within the nanogap between closely spaced metallic surfaces to more strongly amplify Raman signals than the cases with molecules on metal surfaces. Nanoparticle-based NERS offers extraordinarily strong Raman signals and a plethora of opportunities in sensing, imaging and many different types of biomedical applications. Despite its potential, several challenges still remain for NERS to be widely useful in real-world applications. This Perspective introduces various plasmonic nanogap configurations with nanoparticles, discusses key advances and critical challenges while addressing possible misunderstandings in this field, and provides future directions for NERS to generate stronger, more uniform, and stable signals over a large number of structures for practical applications.

Tetrahedral DNA Framework-Based Spherical Nucleic Acids for Efficient siRNA Delivery

Spherical nucleic acids (SNAs) hold substantial therapeutic potential for the delivery of small interfering RNAs (siRNAs). Nevertheless, their potential remains largely untapped due to the challenges of cytosolic delivery. Inspired by the dynamic, spiky architecture of coronavirus, an interface engineering approach based on a tetrahedral DNA framework (tDF) is demonstrated for the development of coronavirus-mimicking SNAs. By exploiting their robustness and precise construction, tDFs are evenly arranged on the surface of core nanoparticles (NPs) with flexible conformations, generating a dynamic, spiky architecture. This spiky architecture in tetrahedral DNA framework-based SNAs (tDF-SNAs) substantially improve siRNAs duplex efficiency from 20 % to 95 %. Meanwhile, tDF-SNAs changed the endocytosis pathway to clathrin-independent cellular engulfment pathway and enhanced the cellular uptake efficiency. Due to these advances, the delivery efficiency of siRNA molecules by tDF-SNAs is 1-2 orders of magnitude higher than that of SNAs, resulting in a 2-fold increase in gene silencing efficacy. These results show promise in the development of bioinspired siRNAs delivery systems for intracellular applications.

Multivalent Weak Protections Ultimately Enable Customizable DNA Grafting on Pristine Ag Colloids for Nanoplasmonics

Silver nanoparticles (AgNPs) have superior plasmonic properties surpassing other metals. However, a long-standing difficulty in valence/density-tunable DNA grafting of AgNPs disfavors their use in DNA-directed nanoplasmonics. Herein a close-to-ideal surface protection of pristine AgNPs against various notorious stability issues of Ag is achieved based on multidentate weak nucleobase bindings of non-programming FSDNA (fish sperm DNA). This further allows grafting of thiolated DNA with tunable valence/density on AgNPs. The end-on format of the thiolated DNA grafts and the very thin FSDNA layer benefit DNA hybridization and plasmon coupling, respectively. Significantly promoted optical coupling and Raman enhancing are achieved. The compatibility of FSDNA-capped AgNPs with Au enables DNA-bonded symmetry-broken Au-Ag heterodimers with strong near-field coupling and an easily seen Fano-induced feature. Our work provides a treasured freedom of using AgNPs in DNA-programmed, better-behaving plasmonic devices.

Empowering DNA-Based Information Processing: Computation and Data Storage

Information processing is a critical topic in the digital age, as silicon-based circuits face unprecedented challenges such as data explosion, immense energy consumption, and approaching physical limits. Deoxyribonucleic acid (DNA), naturally selected as a carrier for storing and using genetic information, possesses unique advantages for information processing, which has given rise to the emerging fields of DNA computing and DNA data storage. To meet the growing practical demands, a wide variety of materials and interfaces have been introduced into DNA information processing technologies, leading to significant advancements. This review summarizes the advances in materials and interfaces that facilitate DNA computation and DNA data storage. We begin with a brief overview of the fundamental functions and principles of DNA computation and DNA data storage. Subsequently, we delve into DNA computing systems based on various materials and interfaces, including microbeads, nanomaterials, DNA nanostructures, hydrophilic-hydrophobic compartmentalization, hydrogels, metal-organic frameworks, and microfluidics. We also explore DNA data storage systems, encompassing encapsulation materials, microfluidics techniques, DNA nanostructures, and living cells. Finally, we discuss the current bottlenecks and obstacles in the fields and provide insights into potential future developments.

Neuromorphic Computing Primitives Using Polymer-Networked Nanoparticles

Nanoparticle networks have potential applications in brain-like computing yet their ability to adopt different states remains unexplored. In this work, we reveal the dynamics of the attachment of polyelectrolytes onto gold nanoparticles (AuNPs), using a bottom-up two-bead-monomer dissipative particle dynamics (TBM-DPD) model to show the heterogeneity of polymer coverage. We found that the use of one polyelectrolyte homopolymer limits the complexity of the possible engineered nanoparticle networks (ENPNs) that can be built. In addressing this challenge, we first found the commensurability rules between the numbers of AuNPs and poly(allylamine hydrochloride)s (PAHs). This gives rise to a well-defined valency of a AuNP which is the maximum number of PAHs that it can accommodate. We further use an engineered block copolymer, which has a conductive middle block to mediate the distance between a dimer of AuNP. We argue that by controlling the length of conductive block that is connecting the AuNPs and their respective topology, we can have ENPNs potentially adopt multiple states necessary for primitive neuromorphic computing.

Freezing Functional Nucleic Acids: From Molecular Reactions to Surface Immobilization

Biochemical reactions are typically slowed down by decreasing temperature. However, accelerated reaction kinetics have been observed for a long time. More recent examples have highlighted the unique role of freezing in fabricating supermaterials, degrading environmental contaminants, and accelerating bioreactions. Functional nucleic acids are DNA or RNA oligonucleotides with versatile properties, including target recognition, catalysis, and molecular co4mputing. In this review, we discuss the current observations and understanding of freezing-facilitated reactions involving functional nucleic acids. Molecular reactions such as ligation/conjugation, cleavage, and hybridization are discussed. Moreover, freezing-induced DNA-nanoparticle conjugations are introduced. Then, we describe our effect in immobilizing DNA on bulk surfaces. Finally, we address some critical questions and research opportunities in the field.

Emerging near-infrared targeting diagnostic and therapeutic strategies for ischemic cardiovascular and cerebrovascular diseases

Ischemic cardiovascular and cerebrovascular diseases (ICCDs), including thrombosis, ischemic stroke and atherosclerosis, represent a significant threat to human health, and there is an urgent requirement for the implementation of emerging diagnostic and therapeutic approaches to improve symptoms and prognosis. As a promising noninvasive modality offering high spatial and temporal resolution with favorable biocompatible properties, near-infrared (NIR) light has demonstrated a vast and profound potential in the biomedical field in recent years. Meanwhile, nanomedicine carriers are undergoing rapid development due to their high specific surface area, elevated drug loading capacity, and unique physicochemical properties. The combination of NIR light with targeted nanoprobes modified with different functional components not only maintains the high penetration depth of NIR irradiation in biological tissues but also significantly enhances the targeting specificity at the lesion site. This strategy allows for the realization of on-demand drug release and photothermal effects, thus inspiring promising avenues for the diagnosis and treatment of ICCDs. However, the clinical translation of NIR imaging and therapy is still hindered by significant obstacles. The existing literature has provided a comprehensive overview of the advancements in NIR-based nanomedicine research. However, there is a notable absence of reviews that summarize the NIR-mediated targeting strategies against ICCDs in imaging and therapy. Therefore, this review concludes the application of the emerging targeting probes combined with NIR radiation for ICCDs classified by molecular targets, analyzes the current challenges, and provides improvement strategies and prospects for further clinical translation. STATEMENT OF SIGNIFICANCE: Ischemic cardiovascular and cerebrovascular diseases (ICCDs) represent a significant threat to human health. Recently, near-infrared (NIR) light combined with targeting probes have been employed for the diagnosis and treatment of ICCDs, offering exceptional advantages including rapid feedback, high penetration depth, on-demand drug release, and favorable biocompatibility. However, there is a notable absence of reviews that summarize the NIR light-mediated targeting strategies for the imaging and therapy of ICCDs. Therefore, this review summarizes the emerging targeting probes combined with NIR light classified by molecular targets, and the proposes potential improvement strategies for clinical translation. This review elucidates the potential and current status of NIR-based techniques in ICCDs, while also serving as a reference point for additional targeted therapeutic strategies for ICCDs.

Oligo-Adenine Derived Secondary Nucleic Acid Frameworks: From Structural Characteristics to Applications

Oligo-adenine (polyA) is primarily known for its critical role in mRNA stability, translational status, and gene regulation. Beyond its biological functions, extensive research has unveiled the diverse applications of polyA. In response to environmental stimuli, single polyA strands undergo distinctive structural transitions into diverse secondary configurations, which are reversible upon the introduction of appropriate counter-triggers. In this review, we systematically summarize recent advances of noncanonical structures derived from polyA, including A-motif duplex, A-cyanuric acid triplex, A-coralyne-A duplex, and T ⋅ A-T triplex. The structural characteristics and mechanisms underlying these conformations under specific external stimuli are addressed, followed by examples of their applications in stimuli-responsive DNA hydrogels, supramolecular fibre assembly, molecular electronics and switches, biosensing and bioengineering, payloads encapsulation and release, and others. A detailed comparison of these polyA-derived noncanonical structures is provided, highlighting their distinctive features. Furthermore, by integrating their stimuli-responsiveness and conformational characteristics, advanced material development, such as pH-cascaded DNA hydrogels and supramolecular fibres exhibiting dynamic structural transitions adapting environmental cues, are introduced. An outlook for future developments is also discussed. These polyA derived, stimuli-responsive, noncanonical structures enrich the arsenal of DNA "toolbox", offering dynamic DNA frameworks for diverse future applications.

From Structure to Application: The Evolutionary Trajectory of Spherical Nucleic Acids

Since the proposal of the concept of spherical nucleic acids (SNAs) in 1996, numerous studies have focused on this topic and have achieved great advances. As a new delivery system for nucleic acids, SNAs have advantages over conventional deoxyribonucleic acid (DNA) nanostructures, including independence from transfection reagents, tolerance to nucleases, and lower immune reactions. The flexible structure of SNAs proves that various inorganic or organic materials can be used as the core, and different types of nucleic acids can be conjugated to realize diverse functions and achieve surprising and exciting outcomes. The special DNA nanostructures have been employed for immunomodulation, gene regulation, drug delivery, biosensing, and bioimaging. Despite the lack of rational design strategies, potential cytotoxicity, and structural defects of this technology, various successful examples demonstrate the bright and convincing future of SNAs in fields such as new materials, clinical practice, and pharmacy.

Co-Assembly of Soft and Hard Nanoparticles into Macroscopic Colloidal Composites with Tailored Mechanical Property and Processability

Colloidal composites, translating the great potential of nanoscale building bricks into macroscopic dimensions, have emerged as an appealing candidate for new materials with applications in optics, energy storage, and biomedicines. However, it remains a key challenge to bridge the size regimes from nanoscopic colloidal particles to macroscale composites possessing mechanical robustness. Herein, a bottom-up approach is demonstrated to manufacture colloidal composites with customized macroscopic forms by virtue of the co-assembly of nanosized soft polymeric micelles and hard inorganic nanoparticles. Upon association, the hairy micellar corona can bind with the hard nanoparticles, linking individual hard constituents together in a soft-hard alternating manner to form a collective entity. This permits the integration of block copolymer micelles with controlled amounts of hard nanoparticles into macroscopic colloidal composites featuring diverse internal microstructures. The resultant composites showed tunable microscale mechanical strength in a range of 90-270 MPa and macroscale mechanical strength in a range of 7-42 MPa for compression and 2-24 MPa for bending. Notably, the incorporation of soft polymeric micelles also imparts time- and temperature-dependent dynamic deformability and versatile capacity to the resulting composites, allowing their application in the low-temperature plastic processing for functional fused silica glass.

Nucleic acid-responsive smart systems for controlled cargo delivery

Stimulus-responsive delivery systems allow controlled, highly regulated, and efficient delivery of various cargos while minimizing side effects. Owing to the unique properties of nucleic acids, including the ability to adopt complex structures by base pairing, their easy synthesis, high specificity, shape memory, and configurability, they have been employed in autonomous molecular motors, logic circuits, reconfigurable nanoplatforms, and catalytic amplifiers. Moreover, the development of nucleic acid (NA)-responsive intelligent delivery vehicles is a rapidly growing field. These vehicles have attracted much attention in recent years due to their programmable, controllable, and reversible properties. In this work, we review several types of NA-responsive controlled delivery vehicles based on locks and keys, including DNA/RNA-responsive, aptamer-responsive, and CRISPR-responsive, and summarize their advantages and limitations.

Surface Orthogonal Patterning and Bidirectional Self-Assembly of Nanoparticles Tethered by V-Shaped Diblock Copolymers

We investigated the surface orthogonal patterning and bidirectional self-assembly of binary hairy nanoparticles (NPs) constructed by uniformly tethering a single NP with multiple V-shaped AB diblock copolymers using Brownian dynamics simulations in a poor solvent. At low concentration, the chain collapse and microphase separation of binary polymer brushes can lead to the patterning of the NP surface into A- and B-type orthogonal patches with various numbers of domains (valency), n = 1-6, that adopt spherical, linear, triangular, tetrahedral, square pyramidal, and pentagonal pyramidal configurations. There is a linear relationship between the valency and the average ratio of NP diameter to the polymers' unperturbed root-mean-square end-to-end distance for the corresponding valency. The linear slope depends on the grafting density and is independent of the interaction parameters between polymers. At high concentration, the orthogonal patch NPs serve as building blocks and exhibit directional attractions by overlapping the same type of domains, resulting in self-assembly into a series of fascinating architectures depending on the valency and polymer length. Notably, the 2-valent orthogonal patch NPs have the bidirectional bonding ability to form the two-dimensional (2D) square NP arrays by two distinct pathways. Simultaneously patching A and B blocks enables the one-step formation of 2D square arrays via bidirectional growth, whereas step-by-step patching causes the directional formation of 1D chains followed by 2D square arrays. Moreover, the gap between NPs in the 2D square arrays is related to the polymer length but independent of the NP diameter. These 2D square NP arrays are of significant value in practical applications such as integrated circuit manufacturing and nanotechnology.

Welded Gold Nanoparticle Assemblies Defined Plasmonic Coupling

Nanoparticle assemblies with interparticle ohmic contacts are crucial for nanodevice fabrication. Despite tremendous progress in DNA-programmable nanoparticle assemblies, seamlessly welding discrete components into welded continuous three-dimensional (3D) configurations remains challenging. Here, we introduce a single-stranded DNA-encoded strategy to customize welded metal nanostructures with tunable morphologies and plasmonic properties. We demonstrate the precise welding of gold nanoparticle assemblies into continuous metal nanostructures with interparticle ohmic contacts through chemical welding in solution. We find that the welded gold nanoparticle assemblies show a consistent morphology with welded efficiency over 90%, such as the rod-like, triangular, and tetrahedral metal nanostructures. Next, we show the versatility of this strategy by welding gold nanoparticle assemblies of varied sizes and shapes. Furthermore, the experiment and simulation show that the welded gold nanoparticle assemblies exhibit defined plasmonic coupling. This single-stranded DNA encoded welding system may provide a new route for accurately building functional plasmonic nanomaterials and devices.

Formation of Linear Plasmonic Heterotrimers Using Nanoparticle Docking to DNA Origami Cages

The fabrication of complex assemblies with interesting collective properties from plasmonic nanoparticles (NPs) is often challenging. While DNA-directed self-assembly has emerged as one of the most promising approaches to forming such complex assemblies, the resulting structures tend to have large variability in gap sizes and shapes, as the DNA strands used to organize these particles are flexible, and the polydispersity of the NPs leads to variability in these critical structural features. Here, we use a new strategy termed docking to DNA origami cages (D-DOC) to organize spherical NPs into a linear heterotrimer with a precisely defined geometrical arrangement. Instead of binding NPs to the exterior of the DNA templates, D-DOC binds the NPs to either the interior or the opening of a 3D cage, which significantly reduces the variability of critical structural features by incorporating multiple diametrically arranged capture strands to tether NPs. Additionally, such a spatial arrangement of the capture strand can work synergistically with shape complementarity to achieve tighter confinement. To assemble NPs via D-DOC, we developed a multistep assembly process that first encapsulates an NP inside a cage and then binds two other NPs to the openings. Microscopic characterization shows low variability in the bond angles and gap sizes. Both UV-vis absorption and surface-enhanced Raman scattering (SERS) measurements showed strong plasmonic coupling that aligned with predictions by electrodynamic simulations, further confirming the precision of the assembly. These results suggest D-DOC could open new opportunities in biomolecular sensing, SERS and fluorescence spectroscopies, and energy harvesting through the self-assembly of NPs into more complex 3D assemblies.

Weakly ionized gold nanoparticles amplify immunoassays for ultrasensitive point-of-care sensors

Gold nanoparticle-based lateral flow immunoassays (AuNP LFIAs) are widely used point-of-care (POC) sensors for in vitro diagnostics. However, the sensitivity limitation of conventional AuNP LFIAs impedes the detection of trace biomarkers. Several studies have explored the size and shape factors of AuNPs and derivative nanohybrids, showing limited improvements or enhanced sensitivity at the cost of convenience and affordability. Here, we investigated surface chemistry on the sensitivity of AuNP LFIAs. By modifying surface ligands, a surface chemistry strategy involving weakly ionized AuNPs enables ultrasensitive naked-eye LFIAs (~100-fold enhanced sensitivity). We demonstrated how this surface chemistry-amplified immunoassay approach modulates nanointerfacial bindings to promote antibody adsorption and higher activity of adsorbed antibodies. This surface chemistry design eliminates complex nanosynthesis, auxiliary devices, or additional reagents while efficiently improving sensitivity with advantages: simplified fabrication process, excellent reproducibility and reliability, and ultrasensitivity toward various biomarkers. The surface chemistry using weakly ionized AuNPs represents a versatile approach for sensitizing POC sensors.

Monodispersed and Monofunctionalized DNA-Caged Au Nano-Clusters with Enhanced Optical Properties for STED Imaging

The performance of Stimulated Emission Depletion (STED) microscopy depends critically on the fluorescent probe. Ultrasmall Au nanoclusters (Au NCs) exhibit large Stokes shift, and good stimulated emission response, which are potentially useful for STED imaging. However, Au NCs are polydispersed in size, sensitive to the surrounding environment, and difficult to control surface functional group stoichiometry, which results in reduced density and high heterogeneity in the labeling of biological structures. Here, this limitation is overcome by developing a method to encapsulate ultrasmall Au NCs with DNA cages, which yielded monodispersed, and monofunctionalized Au NCs that are long-term stable. Moreover, the DNA-caging also greatly improved the fluorescence quantum yield and photostability of Au NCs. In STED imaging, the DNA-caged Au NCs yielded ≈40 nm spatial resolution and are able to resolve microtubule line shapes with good labeling density and homogeneity. In contrast, without caging, the Au NCs-DNA conjugates only achieved ≈55 nm resolution and yielded spotted, poorly resolved microtubule structures, due to the presence of aggregates. Overall, a method is developed to achieve precise surface functionalization and greatly improve the monodispersity, stability, as well as optical properties of Au NCs, providing a promising class of fluorescent probes for STED imaging.

Concept and Development of Algebraic Topological Framework Nucleic Acids

Nucleic acids are considered as promising materials for developing exquisite nanostructures from one to three dimensions. The advances of DNA nanotechnology facilitate ingenious design of DNA nanostructures with diverse shapes and sizes. Especially, the algebraic topological framework nucleic acids (ATFNAs) are functional DNA nanostructures that engineer guest molecules (e. g., nucleic acids, proteins, small molecules, and nanoparticles) stoichiometrically and spatially. The intrinsic precise properties and tailorable functionalities of ATFNAs hold great promise for biological applications, such as cell recognition and immunotherapy. This Perspective highlights the concept and development of precisely assembled ATFNAs, and outlines the new frontiers and opportunities for exploiting the structural advantages of ATFNAs for biological applications.

Binding Site Programmable Self-Assembly of 3D Hierarchical DNA Origami Nanostructures

DNA nanotechnology has broad applications in biomedical drug delivery and programmable materials. Characterization of the self-assembly of DNA origami and quantum dots (QDs) is necessary for the development of new DNA-based nanostructures. We use computation and experiment to show that the self-assembly of 3D hierarchical nanostructures can be controlled by programming the binding site number and their positions on DNA origami. Using biotinylated pentagonal pyramid wireframe DNA origamis and streptavidin capped QDs, we demonstrate that DNA origami with 1 binding site at the outer vertex can assemble multimeric origamis with up to 6 DNA origamis on 1 QD, and DNA origami with 1 binding site at the inner center can only assemble monomeric and dimeric origamis. Meanwhile, the yield percentages of different multimeric origamis are controlled by the QD:DNA-origami stoichiometric mixing ratio. DNA origamis with 2 binding sites at the αγ positions (of the pentagon) make larger nanostructures than those with binding sites at the αβ positions. In general, increasing the number of binding sites leads to increases in the nanostructure size. At high DNA origami concentration, the QD number in each cluster becomes the limiting factor for the growth of nanostructures. We find that reducing the QD size can also affect the self-assembly because of the reduced access to the binding sites from more densely packed origamis.

Universal Click-Chemistry Approach for the DNA Functionalization of Nanoparticles

Nanotechnology has revolutionized the fabrication of hybrid species with tailored functionalities. A milestone in this field is the deoxyribonucleic acid (DNA) conjugation of nanoparticles, introduced almost 30 years ago, which typically exploits the affinity between thiol groups and metallic surfaces. Over the last decades, developments in colloidal research have enabled the synthesis of an assortment of nonmetallic structures, such as high-index dielectric nanoparticles, with unique properties not previously accessible with traditional metallic nanoparticles. However, to stabilize, integrate, and provide further functionality to nonmetallic nanoparticles, reliable techniques for their functionalization with DNA will be crucial. Here, we combine well-established dibenzylcyclooctyne-azide click-chemistry with a simple freeze-thaw method to achieve the functionalization of silica and silicon nanoparticles, which form exceptionally stable colloids with a high DNA surface density of ∼0.2 molecules/nm2. Furthermore, we demonstrate that these functionalized colloids can be self-assembled into high-index dielectric dimers with a yield of over 50% via the use of DNA origami. Finally, we extend this method to functionalize other important nanomaterials, including oxides, polymers, core-shell, and metal nanostructures. Our results indicate that the method presented herein serves as a crucial complement to conventional thiol functionalization chemistry and thus greatly expands the toolbox of DNA-functionalized nanoparticles currently available.

DNA Origami Plasmonic Nanoantenna for Programmable Biosensing of Multiple Cytokines in Cancer Immunotherapy

Herein, we report a DNA origami plasmonic nanoantenna for the programmable surface-enhanced Raman scattering (SERS) detection of cytokine release syndrome (CRS)-associated cytokines (e.g., tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ)) in cancer immunotherapy. Typically, the nanoantenna was made of self-assembled DNA origami nanotubes (diameter: ∼19 nm; length: ∼90 nm) attached to a silver nanoparticle-modified silicon wafer (AgNP/Si). Each DNA origami nanotube contains one miniature gold nanorod (AuNR) inside (e.g., length: ∼35 nm; width: ∼7 nm). Intriguingly, TNF-α and IFN-γ logically regulate the opening of the nanotubes and the dissociation of the AuNRs from the origami structure upon binding to their corresponding aptamers. On this basis, we constructed a complete set of Boolean logic gates that read cytokine molecules as inputs and return changes in Raman signals as outputs. Significantly, we demonstrated that the presented system enables the quantification of TNF-α and IFN-γ in the serum of tumor-bearing mice receiving different types of immunotherapies (e.g., PD1/PD-L1 complex inhibitors and STING agonists). The sensing results are consistent with those of the ELISA. This strategy fills a gap in the use of DNA origami for the detection of multiple cytokines in real systems.

DNA-Programmed Four-Bit Quaternary Fluorescence Encoding (FLUCO) Enables 51-Colored Bioimaging Analysis

Color encoding plays a crucial role in painting, digital photography, and spectral analysis. Achieving accurate, target-responsive color encoding at the molecular level has the potential to revolutionize scientific research and technological innovation, but significant challenges persist. Here, we propose a multibit DNA self-assembly system based on computer-aided design (CAD) technology, enabling accurate, target-responsive, amplified color encoding at the molecular level, termed fluorescence encoding (FLUCO). As a model, we establish a quaternary FLUCO system using four-bit DNA self-assembly, which can accurately encode 51 colors, presenting immense potential in applications such as spatial proteomic imaging and multitarget analysis. Notably, FLUCO enables the simultaneous imaging of multiple targets exceeding the limitations of channels using conventional imaging equipment, and marks the integration of computer science for molecular encoding and decoding. Overall, our work paves the way for target-responsive, controllable molecular encoding, facilitating spatial omics analysis, exfoliated cell analysis, and high-throughput liquid biopsy.

DNA-Mediated Magnetic-Dimer Assembly for Fault-Free Ultra-High-Field Magnetic Resonance Imaging of Tumors

Ultra-high-field (UHF) magnetic resonance imaging (MRI) stands as a pivotal cornerstone in biomedical imaging, yet the challenge of false imaging persists, constraining its full potential. Despite the development of dual-mode contrast agents improving conventional MRI, their effectiveness in UHF remains suboptimal due to the high magnetic moment, resulting in diminished T1 relaxivity and excessively enhanced T2 relaxivity. Herein, we report a DNA-mediated magnetic-dimer assembly (DMA) of iron oxide nanoparticles that harnesses UHF-tailored nanomagnetism for fault-free UHF-MRI. DMA exhibits a dually enhanced longitudinal relaxivity of 4.42 mM-1·s-1 and transverse relaxivity of 26.23 mM-1·s-1 at 9 T, demonstrating a typical T1-T2 dual-mode UHF-MRI contrast agent. Importantly, DMA leverages T1-T2 dual-modality image fusion to achieve artifact-free breast cancer visualization, effectively filtering interference from hundred-micrometer-level false-positive signals with unprecedented precision. The UHF-tailored T1-T2 dual-mode DMA contrast agents hold promise for elevating the accuracy of MR imaging in disease diagnosis.

Symmetry-Breaking of Nanoparticle Surface Function Via Conformal DNA Design

Asymmetric surface functionalization of complex nanoparticles to control their directional self-assembly remains a considerable challenge. Here, we demonstrated a conformal DNA design strategy for flexible remodeling of the surface of complex nanoparticles, taking Au nanobipyramids (AuNBPs) as a model. We sheathed one or both tips of AuNBPs into conformal DNA origami with an exceptionally accurate orientation control. Such asymmetrically and symmetrically distributed surface patches possess regioselective, sequence, and site-specific DNA binding capabilities. As a result, we realized a series of prototypical multicomponent "colloidal molecules" made of AuNBPs and Au nanospheres (AuNSs) with defined directionality and number of "bonding valence" as well as 1D and 3D hierarchical assemblies, e.g., inverse core-satellites of AuNBPs and AuNSs, side-by-side and tip-to-tip linear assemblies of AuNBPs, and 3D helical superstructures of AuNBPs with tunable twists. These findings inspire new opportunities for nanoparticle surface engineering and the high-order self-assembly of nanoarchitectures with higher complexity and broadened functionalities.

Catalytic Gold Nanoparticle Assembly Programmed by DNAzyme Circuits

Assembled gold nanoparticle (AuNP) superstructures can generate unique physicochemical characteristics and be used in various applications, thus becoming an attractive research field. Recently, several DNA-assisted gold nanoparticle assembly methods have been rigorously developed that typically require a non-catalytic equimolar molecular assembly to guarantee the designed assembly. Although efficient and accurate, exploring such non-catalytic nanoparticle assemblies in the complex cellular milieu under low trigger concentrations remains challenging. Therefore, developing a catalytic method that facilitates gold nanoparticle assemblies with relatively low DNA trigger concentrations is desirable. In this report, a catalytic method to program gold nanoparticle assemblies by DNAzyme circuits is presented, where only a small number of DNA triggers are able to induce the production of a large number of the desired nanoparticle assemblies. The feasibility of using logic DNAzyme circuits to control catalytic nanoparticle assemblies is experimentally verified. Additionally, catalytic AuNP assembly systems are established with cascading and feedback functions. The work provides an alternative research direction to enrich the tool library of nanoparticle assembly and their application in biosensing and nanomedicine.

Programmable DNA Interphase Layers for High-Performance Anode-Free Lithium Metal Batteries

Anode-free lithium (Li) metal batteries are promising candidates for advanced energy storage, attributed to their appealing characteristics such as high energy density, low cost, and convenient production. However, their major challenges lie in the poor cycling and rate performance owing to the inferior reversibility and kinetics of Li plating and stripping, which significantly hinder their real-world applications. Here, it is demonstrated that deoxyribonucleic acid (DNA), the most important genetic material in nature, can serve as a highly programmable interphase layer for innovation of anode-free Li metal batteries. It is found that the abundant base pairs in DNA can contribute transient Li-N bonds that facilitate homogeneous Li+ flux, thus resulting in excellent Li plating/stripping kinetics and reversibility even at a harsh areal current of 15 mA cm-2. The anode-free LiFePO4 full batteries based on an ultrathin (0.12 µm) and ultralight (≈0.01 mg cm-2) DNA interphase layer show high CEs (≈99.1%) over 400 cycles, corresponding to an increase of ≈186% compared with bare copper (Cu) foil. These results shed light on the excellent programmability of DNA as a new family of interphase materials for anode-free batteries, and provide a new paradigm for future battery innovation toward high programmability, high sustainability, and remarkable electrochemical performance.

Programmable Colloids with Analogous Hypercoordination Complex Architectures

Colloidal molecule clusters (CMCs) are promising building blocks with molecule-like symmetry, offering exceptional synergistic properties for applications in plasmonics and catalysis. Traditional CMC fabrication has been limited to simple molecule-like structures utilizing isotropic particles. Here, we employ molecular dynamics simulation to investigate the co-assembly of anisotropic nanorods (NRs) and the stimulus-responsive polymer (SRP) via reversible adsorption. The results of the simulation show that it is possible to fabricate hypercoordination complex structures with high symmetry from the co-assembly of NRs and the SRP, even in analogy to the Th(BH4)4 structure. The coordination number of these CMCs can be precisely programmed by adjusting the shape and size of the ends of the NRs and the SRP cohesion energy. Furthermore, a finite-difference time-domain simulation indicates these hypercoordination structures exhibit significantly enhanced optical activity and plasmonic coupling effects. These findings introduce a new design approach for complex molecule-like structures utilizing anisotropic nanoparticles and may expand the applications of CMCs in photonics.

Intelligent Biomaterialomics: Molecular Design, Manufacturing, and Biomedical Applications

Materialomics integrates experiment, theory, and computation in a high-throughput manner, and has changed the paradigm for the research and development of new functional materials. Recently, with the rapid development of high-throughput characterization and machine-learning technologies, the establishment of biomaterialomics that tackles complex physiological behaviors has become accessible. Breakthroughs in the clinical translation of nanoparticle-based therapeutics and vaccines have been observed. Herein, recent advances in biomaterials, including polymers, lipid-like materials, and peptides/proteins, discovered through high-throughput screening or machine learning-assisted methods, are summarized. The molecular design of structure-diversified libraries; high-throughput characterization, screening, and preparation; and, their applications in drug delivery and clinical translation are discussed in detail. Furthermore, the prospects and main challenges in future biomaterialomics and high-throughput screening development are highlighted.

DNA as a universal chemical substrate for computing and data storage

DNA computing and DNA data storage are emerging fields that are unlocking new possibilities in information technology and diagnostics. These approaches use DNA molecules as a computing substrate or a storage medium, offering nanoscale compactness and operation in unconventional media (including aqueous solutions, water-in-oil microemulsions and self-assembled membranized compartments) for applications beyond traditional silicon-based computing systems. To build a functional DNA computer that can process and store molecular information necessitates the continued development of strategies for computing and data storage, as well as bridging the gap between these fields. In this Review, we explore how DNA can be leveraged in the context of DNA computing with a focus on neural networks and compartmentalized DNA circuits. We also discuss emerging approaches to the storage of data in DNA and associated topics such as the writing, reading, retrieval and post-synthesis editing of DNA-encoded data. Finally, we provide insights into how DNA computing can be integrated with DNA data storage and explore the use of DNA for near-memory computing for future information technology and health analysis applications.

Programmable Atom-Like Nanoparticle Reporters for High-Precision Urinalysis of In Situ Membrane Proteins

The expression of disease-specific membrane proteins (MPs) is a crucial indicator for evaluating the onset and progression of diseases. Urinalysis of in situ MPs has the potential for point-of-care disease diagnostics, yet remains challenging due to the lack of molecular reporter to transform the expression information of in situ MPs into the measurable urine composition. Herein, a series of tetrahedral DNA frameworks (TDFs) are employed as the cores of programmable atom-like nanoparticles (PANs) to direct the self-assembly of PAN reporters with defined ligand valence and spatial distribution. With the rational spatial organization of ligands, the interaction between PAN reporters and MPs exhibits superior stability on cell-membrane interface under renal tubule-mimic fluid microenvironment, thus enabling high-fidelity conversion of MPs expression level into binding events and reverse assessment of in situ MP levels via measurement of the renal clearance efficiency of PAN reporters. Such PAN reporter-mediated signal transformation mechanism empowers urinalysis of the onset of acute kidney injury at least 6 h earlier than the existing methods with an area under the curve of 100%. This strategy has the potential for urinalysis of a variety of in situ membrane proteins.

Topological Single-stranded DNA Encoding and Programmable Assembly of Molecular Nanostructures for NIR-II Cancer Theranostics

Molecular nanotechnology promises to offer privileged access to developing NIR-II materials with precise structural and functional manipulation for transformable theranostic applications. However, the lack of an affordable, yet general, method makes this goal currently inaccessible. By virtue of the intriguing nucleic acid chemistry, here we present an artificial base-directed topological single-strand DNA encoding design that enables one-step synthesis of valence-controlled NIR-II molecular nanostructures and spatial assembly of these nanostructures to modulate their behaviors in living systems. As proof-of-concept studies, we construct ultrasmall Ag2 S quantum dots and pH-responsive, size-tunable CuS assemblies for in vivo NIR-II fluorescence imaging and deep tumor photothermal therapy. This work paves a new way for creating functionally diversified architectures and broadens the scope of DNA-encoded material engineering.

Photo-Induced Self-assembly of Copolymer-Capped Nanoparticles into Colloidal Molecules

Colloidal molecules (CMs) are precisely defined assemblies of nanoparticles (NPs) that mimic the structure of real molecules, but externally programming the precise self-assembly of CMs is still challenging. In this work, we show that the photo-induced self-assembly of complementary copolymer-capped binary NPs can be precisely controlled to form clustered ABx or linear (AB)y CMs at high yield (x is the coordination number of NP-Bs, and y is the repeating unit number of AB clusters). Under UV light irradiation, photolabile p-methoxyphenacyl groups of copolymers on NP-A*s are converted to carboxyl groups (NP-A), which react with tertiary amines of copolymers on NP-B to trigger the directional NP bonding. The x value of ABx can be precisely controlled between 1 and 3 by varying the irradiation duration and hence the amount of carboxyl groups generated on NP-As. Moreover, when NP-A* and NP-B are irradiated after mixing, the assembly process generates AB clusters or linear (AB)y structures with alternating sequence of the binary NPs. This assembly approach offers a simple yet non-invasive way to externally regulate the formation of various CMs on demand without the need of redesigning the surface chemistry of NPs for use in drug delivery, diagnostics, optoelectronics, and plasmonic devices.

Mercury-Mediated Epitaxial Accumulation of Au Atoms for Stained Hydrogel-Improved On-Site Mercury Monitoring

Trivalent Au ions are easily reduced to be zerovalent atoms by coexisting reductant reagents, resulting in the subsequent accumulation of Au atoms and formation of plasmonic nanostructures. In the absence of stabilizers or presence of weak stabilizers, aggregative growth of Au nanoparticles (NPs) always occurs, and unregular multidimensional Au materials are consequently constructed. Herein, the addition of nanomole-level mercury ions can efficiently prevent the epitaxial accumulation of Au atoms, and separated Au NPs with mediated morphologies and superior plasmonic characteristics are obtained. Experimental results and theoretical simulation demonstrate the Hg-concentration-reliant formation of plasmonic nanostructures with their mediated sizes and shapes in the presence of weak reductants. Moreover, the sensitive plasmonic responses of reaction systems exhibit selectivity comparable to that of Hg species. As a concept of proof, polymeric carbon dots (CDs) were used as the initial reductant, and the reactions between trivalent Au and CDs were studies. Significantly, Hg atoms prevent the epitaxial accumulation of Au atoms, and plasmonic NPs with decreased sizes were in situ synthesized, corresponding to varied surface plasmonic resonance absorption performance of the CD-induced hybrids. Moreover, with the integration of sensing substrates of CD-doped hydrogels, superior response stabilities, analysis selectivity, and sensitivity of Hg2+ ions were achieved on the basis of the mercury-mediated in situ chemical reactions between trivalent Au ions and reductant CDs. Consequently, a high-performance sensing strategy with the use of Au NP-staining hydrogels (nanostaining hydrogels) was exhibited. In addition to Hg sensing, the nanostaining hydrogels facilitated by doping of emerging materials and advanced chem/biostrategies can be developed as high-performance on-site monitoring routes to various pollutant species.

Supramolecular Integration of Multifunctional Nanomaterial by Mannose-Decorated Azocalixarene with Ginsenoside Rb1 for Synergistic Therapy of Rheumatoid Arthritis

The complexity and progressive nature of diseases require the exploitation of multifunctional materials. However, introducing a function inevitably increases the complexity of materials, which complicates preparation and decreases reproducibility. Herein, we report a supramolecular integration of multifunctional nanomaterials based on mannose-modified azocalix[4]arene (ManAC4A) and ginsenoside Rb1 (Rb1), which showed advances of simplicity and reproducibility. ManAC4A possesses reactive oxygen species (ROS) scavenging capacity and hypoxia-responsiveness, together with macrophage-targeting and induction functionality. Collectively, the Rb1@ManAC4A assembly simply prepared by two components is integrated with multifunction, including triple targeting (ELVIS targeting, macrophage-targeting, and hypoxia-targeted release) and triple therapy (ROS scavenging, macrophage polarization, and the anti-inflammatory effect of Rb1). The spontaneous assembly and recognition of ManAC4A, with its precise structure and molecular weight, facilitated the simple and straightforward preparation of Rb1@ManAC4A, leading to excellent batch consistency. Progress in simplicity and reproducibility, as directed by this research, will catalyze the clinical translation of multifunctional materials.

Luminescent Gold Nanoparticles with Discrete DNA Valences for Precisely Controlled Transport at the Subcellular Level

Ultrasmall luminescent gold nanoparticles (AuNPs) with excellent capabilities to cross biological barriers offer great promise in designing intelligent model nanomedicines for investigating structure-property relationships at the subcellular level. However, the strict surface controllability of ultrasmall AuNPs is challenging because of their small size. Herein, we report a facile in situ method for precisely controlling DNA aptamer valences on the surface of luminescent AuNPs with emission in the second near-infrared window using a phosphorothioate-modified DNA aptamer, AS1411, as a template. The discrete DNA aptamer number of AS1411-functionalized AuNPs (AS1411-AuNPs, ≈1.8 nm) with emission at 1030 nm was controlled in one aptamer (V1), two aptamers (V2), and four aptamers (V4). It was then discovered that not only the tumor-targeting efficiencies but also the subcellular transport of AS1411-AuNPs were precisely dependent on valences. A slight increase in valence from V1 to V2 increased tumor-targeting efficiencies and resulted in higher nucleus accumulation, whereas a further increase in valence (e.g., V4) significantly increased tumor-targeting efficiencies and led to higher cytomembrane accumulation. These results provide a basis for the strict surface control of nanomedicines in the precise regulation of in vivo transport at the subcellular level and their translation into clinical practice in the future.

DNA-Based Gold Nanoparticle Assemblies: From Structure Constructions to Sensing Applications

Gold nanoparticles (Au NPs) have become one of the building blocks for superior assembly and device fabrication due to the intrinsic, tunable physical properties of nanoparticles. With the development of DNA nanotechnology, gold nanoparticles are organized in a highly precise and controllable way under the mediation of DNA, achieving programmability and specificity unmatched by other ligands. The successful construction of abundant gold nanoparticle assembly structures has also given rise to the fabrication of a wide range of sensors, which has greatly contributed to the development of the sensing field. In this review, we focus on the progress in the DNA-mediated assembly of Au NPs and their application in sensing in the past five years. Firstly, we highlight the strategies used for the orderly organization of Au NPs with DNA. Then, we describe the DNA-based assembly of Au NPs for sensing applications and representative research therein. Finally, we summarize the advantages of DNA nanotechnology in assembling complex Au NPs and outline the challenges and limitations in constructing complex gold nanoparticle assembly structures with tailored functionalities.

Semiconducting Polymer Nanospherical Nucleic Acid Probe for Transcriptomic Imaging of Cancer Chemo-Immunotherapy

Real-time in vivo imaging of RNA can enhance the understanding of physio-pathological processes. However, most nucleic acid-based sensors have poor resistance to nucleases and limited photophysical properties, making them suboptimal for this purpose. To address this, a semiconducting polymer nanospherical nucleic acid probe (SENSE) for transcriptomic imaging of cancer immunity in living mice is developed. SENSE comprises a semiconducting polymer (SP) backbone covalently linked with recognition DNA strands, which are complemented by dye-labeled signal DNA strands. Upon detection of targeted T lymphocyte transcript (Gzmb: granzyme B), the signal strands are released, leading to a fluorescence enhancement correlated to transcript levels with superb sensitivity. The always-on fluorescence of the SP core also serves as an internal reference for tracking SENSE uptake in tumors. Thus, SENSE has the dual-signal channel that enables ratiometric imaging of Gzmb transcripts in the tumor of living mice for evaluating chemo-immunotherapy; moreover, it has demonstrated sensitivity and specificity comparable to flow cytometry and quantitative polymerase chain reaction,  yet offering a faster and simpler means of T cell detection in resected tumors. Therefore, SENSE represents a promising tool for in vivo RNA imaging.

DNA Framework Programmed Conformational Reconstruction of Antibody Complementary Determining Region

The conformation of complementary determining region (CDR) is crucial in dictating its specificity and affinity for binding with an antigen, making it a focal point in artificial antibody engineering. Although desirable, programmable scaffolds that can regulate the conformation of individual CDRs with nanometer precision are still lacking. Here, we devise a strategy to program the CDR conformation by anchoring both ends of a free CDR loop to specific sites of a DNA framework structure. This method allows us to define the span of a single CDR loop with an ∼2 nm resolution. Using this approach, we create a series of DNA framework based artificial antibodies (DNFbodies) with varied CDR loop spans, leading to different antibody-antigen binding affinities. We find that an optimized single CDR loop (∼2.3 nm span) exhibits ∼3-fold improved affinity relative to natural antibodies, confirming the critical role of the CDR conformation. This study may inspire the rational design of artificial antibodies.