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The application of lipid-based nanoparticles for COVID-19 vaccines and transthyretin-mediated amyloidosis treatment have highlighted their potential for translation to cancer therapy. However, their use in delivering drugs to solid tumors is limited by ineffective targeting, heterogeneous organ distribution, systemic inflammatory responses, and insufficient drug accumulation at the tumor. Instead, the use of lipid-based nanoparticles to remotely activate immune system responses is an emerging effective strategy. Despite this approach showing potential for treating hematological cancers, its application to treat solid tumors is hampered by the selection of eligible targets, tumor heterogeneity, and ineffective penetration of activated T cells within the tumor. Notwithstanding, the use of lipid-based nanoparticles for immunotherapy is projected to revolutionize cancer therapy, with the ultimate goal of rendering cancer a chronic disease. However, the translational success is likely to depend on the use of predictive tumor models in preclinical studies, simulating the complexity of the tumor microenvironment (e.g., the fibrotic extracellular matrix that impairs therapeutic outcomes) and stimulating tumor progression. This review compiles recent advances in the field of antitumor lipid-based nanoparticles and highlights emerging therapeutic approaches (e.g., mechanotherapy) to modulate tumor stiffness and improve T cell infiltration, and the use of organoids to better guide therapeutic outcomes.

Synthetic cell exoskeletons created from abiotic materials have attracted interest in materials science and biotechnology, as they can regulate cell behavior and create new functionalities. Here, a facile strategy is reported to mimic microalgal sporulation with on-demand germination and locomotion via responsive metal-phenolic networks (MPNs). Specifically, MPNs with tunable thickness and composition are deposited on the surface of microalgae cells via one-step coordination, without any loss of cell viability or intrinsic cell photosynthetic properties. The MPN coating keeps the cells in a dormant state, but can be disassembled on-demand in response to environmental pH or chemical stimulus, thereby reviving the microalgae within 1 min. Moreover, the artificial sporulation of microalgae resulted in resistance to environmental stresses (e.g., metal ions and antibiotics) akin to the function of natural sporulation. This strategy can regulate the life cycle of complex cells, providing a synthetic strategy for designing hybrid microorganisms.

Tailoring the hydrophobicity of supramolecular assembly building blocks enables the fabrication of well‐defined functional materials. However, the selection of building blocks used in the assembly of metal–phenolic networks (MPNs), an emerging supramolecular assembly platform for particle engineering, has been essentially limited to hydrophilic molecules. Herein, we synthesized and applied biscatechol‐functionalized hydrophobic polymers (poly(methyl acrylate) (PMA) and poly(butyl acrylate) (PBA)) as building blocks to engineer MPN particle systems (particles and capsules). Our method allowed control over the shell thickness (e.g., between 10 and 21 nm), stiffness (e.g., from 10 to 126 mN m−1), and permeability (e.g., 28–72 % capsules were permeable to 500 kDa fluorescein isothiocyanate‐dextran) of the MPN capsules by selection of the hydrophobic polymer building blocks (PMA or PBA) and by controlling the polymer concentration in the MPN assembly solution (0.25–2.0 mM) without additional/engineered assembly processes. Molecular dynamics simulations provided insights into the structural states of the hydrophobic building blocks during assembly and mechanism of film formation. Furthermore, the hydrophobic MPNs facilitated the preparation of fluorescent‐labeled and bioactive capsules through postfunctionalization and also particle–cell association engineering by controlling the hydrophobicity of the building blocks. Engineering MPN particle systems via building block hydrophobicity is expected to expand their use.

Interactions between living cells and nanoparticles are extensively studied to enhance the delivery of therapeutics. Nanoparticles size, shape, stiffness, and surface charge are regarded as the main features able to control the fate of cell-nanoparticle interactions. However, the clinical translation of nanotherapies has so far been limited, and there is a need to better understand the biology of cell-nanoparticle interactions. This study investigates the role of cellular mechanosensitive components in cell-nanoparticle interactions. It is demonstrated that the genetic and pharmacologic inhibition of yes-associated protein (YAP), a key component of cancer cell mechanosensing apparatus and Hippo pathway effector, improves nanoparticle internalization in triple-negative breast cancer cells regardless of nanoparticle properties or substrate characteristics. This process occurs through YAP-dependent regulation of endocytic pathways, cell mechanics, and membrane organization. Hence, the study proposes targeting YAP may sensitize triple-negative breast cancer cells to chemotherapy and increase the selectivity of nanotherapy.

Coordination assembly offers a versatile means to developing advanced materials for various applications. However, current strategies for assembling metal-organic networks into nanoparticles (NPs) often face challenges such as the use of toxic organic solvents, cytotoxicity because of synthetic organic ligands, and complex synthesis procedures. Herein, we directly assemble metal-organic networks into NPs using metal ions and polyphenols (i.e., metal-phenolic networks (MPNs)) in aqueous solutions without templating or seeding agents. We demonstrate the role of buffers (e.g., phosphate buffer) in governing NP formation and the engineering of the NP physicochemical properties (e.g., tunable sizes from 50 to 270 nm) by altering the assembly conditions. A library of MPN NPs is prepared using natural polyphenols and various metal ions. Diverse functional cargos, including anticancer drugs and proteins with different molecular weights and isoelectric points, are readily loaded within the NPs for various applications (e.g., biocatalysis, therapeutic delivery) by direct mixing, without surface modification, owing to the strong affinity of polyphenols to various guest molecules. This study provides insights into the assembly mechanism of metal-organic complexes into NPs and offers a simple strategy to engineer nanosized materials with desired properties for diverse biotechnological applications.

Nanostructured materials with tunable structures and functionality are of interest in diverse areas. Herein, metal ions are coordinated with quinones through metal‐acetylacetone coordination bonds to generate a class of structurally tunable, universally adhesive, hydrophilic, and pH‐degradable materials. A library of metal‐quinone networks (MQNs) is produced from five model quinone ligands paired with nine metal ions, leading to the assembly of particles, tubes, capsules, and films. Importantly, MQNs show bidirectional pH‐responsive disassembly in acidic and alkaline solutions, where the quinone ligands mediate the disassembly kinetics, enabling temporal and spatial control over the release of multiple components using multilayered MQNs. Leveraging this tunable release and the inherent medicinal properties of quinones, MQN prodrugs with a high drug loading (>89 wt %) are engineered using doxorubicin for anti‐cancer therapy and shikonin for the inhibition of the main protease in the SARS‐CoV‐2 virus.

DNA‐based materials have attracted interest due to the tunable structure and encoded biological functionality of nucleic acids. A simple and general approach to synthesize DNA‐based materials with fine control over morphology and bioactivity is important to expand their applications. Here, we report the synthesis of DNA‐based particles via the supramolecular assembly of tannic acid (TA) and DNA. Uniform particles with different morphologies are obtained using a variety of DNA building blocks. The particles enable the co‐delivery of cytosine‐guanine adjuvant sequences and the antigen ovalbumin in model cells. Intramuscular injection of the particles in mice induces antigen‐specific antibody production and T cell responses with no apparent toxicity. Protein expression in cells is shown using capsules assembled from TA and plasmid DNA. This work highlights the potential of TA as a universal material for directing the supramolecular assembly of DNA into gene and vaccine delivery platforms.

Flexible metal-organic materials are of growing interest owing to their ability to undergo reversible structural transformations under external stimuli. Here, we report flexible metal-phenolic networks (MPNs) featuring stimuli-responsive behavior to diverse solute guests. The competitive coordination of metal ions to phenolic ligands of multiple coordination sites and solute guests (e.g., glucose) primarily determines the responsive behavior of the MPNs, as revealed experimentally and computationally. Glucose molecules can be embedded into the dynamic MPNs upon mixing, leading to the reconfiguration of the metal-organic networks and thus changes in their physicochemical properties for targeting applications. This study expands the library of stimuli-responsive flexible metal-organic materials and the understanding of intermolecular interactions between metal-organic materials and solute guests, which is essential for the rational design of responsive materials for various applications.

The integration of bioactive materials (e.g., proteins and genes) into nanoparticles holds promise in fields ranging from catalysis to biomedicine. However, it is challenging to develop a simple and broadly applicable nanoparticle platform that can readily incorporate distinct biomacromolecules without affecting their intrinsic activity. Herein, a metal-phenolic assembly approach is presented whereby diverse functional nanoparticles can be readily assembled in water by combining various synthetic and natural building blocks, including poly(ethylene glycol), phenolic ligands, metal ions, and bioactive macromolecules. The assembly process is primarily mediated by metal-phenolic complexes through coordination and hydrophobic interactions, which yields uniform and spherical nanoparticles (mostly <200 nm), while preserving the function of the incorporated biomacromolecules (siRNA and five different proteins used). The functionality of the assembled nanoparticles is demonstrated through cancer cell apoptosis, RNA degradation, catalysis, and gene downregulation studies. Furthermore, the resulting nanoparticles can be used as building blocks for the secondary engineering of superstructures via templating and cross-linking with metal ions. The bioactivity and versatility of the platform can potentially be used for the streamlined and rational design of future bioactive materials.

The safe administration of thrombolytic agents is a challenge for the treatment of acute thrombosis. Lipid-based nanoparticle drug delivery technologies present opportunities to overcome the existing clinical limitations and deliver thrombolytic therapy with enhanced therapeutic outcomes and safety. Herein, lipid cubosomes are examined as nanocarriers for the encapsulation of thrombolytic drugs. The lipid cubosomes are loaded with the thrombolytic drug urokinase-type plasminogen activator (uPA) and coated with a low-fouling peptide that is incorporated within a metal-phenolic network (MPN). The peptide-containing MPN (pep-MPN) coating inhibits the direct contact of uPA with the surrounding environment, as assessed by an in vitro plasminogen activation assay and an ex vivo whole blood clot degradation assay. The pep-MPN-coated cubosomes prepared with 22 wt% peptide demonstrate a cell membrane-dependent thrombolytic activity, which is attributed to their fusogenic lipid behavior. Moreover, compared with the uncoated lipid cubosomes, the uPA-loaded pep-MPN-coated cubosomes demonstrate significantly reduced nonspecific cell association (<10% of the uncoated cubosomes) in the whole blood assay, a prolonged circulating half-life, and reduced splenic uPA accumulation in mice. These studies confirm the preserved bioactivity and cell membrane-dependent release of uPA within pep-MPN-coated lipid cubosomes, highlighting their potential as a delivery vehicle for thrombolytic drugs.

Coordination states of metal‐organic materials are known to dictate their physicochemical properties and applications in various fields. However, understanding and controlling coordination sites in metal‐organic systems is challenging. Herein, we report the synthesis of site‐selective coordinated metal‐phenolic networks (MPNs) using flavonoids as coordination modulators. The site‐selective coordination was systematically investigated experimentally and computationally using ligands with one, two, and multiple different coordination sites. Tuning the multimodal Fe coordination with catechol, carbonyl, and hydroxyl groups within the MPNs enabled the facile engineering of diverse physicochemical properties including size, selective permeability (20–2000 kDa), and pH‐dependent degradability. This study expands our understanding of metal‐phenolic chemistry and provides new routes for the rational design of structurally tailorable coordination‐based materials.

Supramolecular complexation is a powerful strategy for engineering materials in bulk and at interfaces. Metal–phenolic networks (MPNs), which are assembled through supramolecular complexes, have emerged as suitable candidates for surface and particle engineering owing to their diverse properties. Herein, we examine the supramolecular dynamics of MPNs during thermal transformation processes. Changes in the local supramolecular network including enlarged pores, ordered aromatic packing, and metal relocation arise from thermal treatment in air or an inert atmosphere, enabling the engineering of metal–oxide networks (MONs) and metal–carbon networks, respectively. Furthermore, by integrating photo‐responsive motifs (i.e., TiO2) and silanization, the MONs are endowed with reversible superhydrophobic (>150°) and superhydrophilic (≈0°) properties. By highlighting the thermodynamics of MPNs and their transformation into diverse materials, this work offers a versatile pathway for advanced materials engineering.

Bio-nanoscience research encompasses studies on the interactions of nanomaterials with biological structures or what is commonly referred to as the biointerface. Fundamental studies on the influence of nanomaterial properties, including size, shape, composition, and charge, on the interaction with the biointerface have been central in bio-nanoscience to assess nanomaterial efficacy and safety for a range of biomedical applications. However, the state of the cells, tissues, or biological models can also influence the behavior of nanomaterials at the biointerface and their intracellular processing. Focusing on the "bio" in bio-nano, this review discusses the impact of biological properties at the cellular, tissue, and whole organism level that influences nanomaterial behavior, including cell type, cell cycle, tumor physiology, and disease states. Understanding how the biological factors can be addressed or exploited to enhance nanomaterial accumulation and uptake can guide the design of better and suitable models to improve the outcomes of materials in nanomedicine.

Engineering coatings with precise physicochemical properties allows for control over the interface of a material and its interactions with the surrounding environment. However, assembling coatings with well‐defined properties on different material classes remains a challenge. Herein, we report a co‐assembly strategy to precisely control the structure and properties (e.g., thickness, adhesion, wettability, and zeta potential) of coatings on various materials (27 substrates examined) using quinone and polyamine building blocks. By increasing the length of the amine building blocks from small molecule diamines to branched amine polymers, we tune the properties of the films, including the thickness (from ca. 5 to ca. 50 nm), interfacial adhesion (0.05 to 5.54 nN), water contact angle (130 to 40°), and zeta potential (−42 to 28 mV). The films can be post‐functionalized through the in situ formation of diverse nanostructures, including nanoparticles, nanorods, and nanocrystals. Our approach provides a platform for the rational design of engineered, substrate‐independent coatings for various applications.

We report a sono-Fenton strategy to mediate the supramolecular assembly of metal–phenolic networks (MPNs) as substrate-independent coatings using phenol and phenyl derivatives as building blocks. The assembly process is initiated from the generation of hydroxyl radicals (.OH) using high-frequency ultrasound (412 kHz), while the metal ions synergistically participate in the production of additional .OH for hydroxylation/phenolation of phenol and phenyl derivatives via the Fenton reaction and also coordinate with the phenolic compounds for film formation. The coating strategy is applicable to various phenol and phenyl derivatives and different metal ions including FeII, FeIII, CuII, and CoII. In addition, the sono-Fenton strategy allows real-time control over the assembly process by turning the high-frequency ultrasound on or off. The properties of the building blocks are maintained in the formed films. This work provides an environmentally friendly and controllable method to expand the application of phenolic coatings for surface engineering.

Functional coatings are of considerable interest because of their fundamental implications for interfacial assembly and promise for numerous applications. Universally adherent materials have recently emerged as versatile functional coatings; however, such coatings are generally limited to catechol, (ortho‐diphenol)‐containing molecules, as building blocks. Here, we report a facile, biofriendly enzyme‐mediated strategy for assembling a wide range of molecules (e.g., 14 representative molecules in this study) that do not natively have catechol moieties, including small molecules, peptides, and proteins, on various surfaces, while preserving the molecule's inherent function, such as catalysis (≈80 % retention of enzymatic activity for trypsin). Assembly is achieved by in situ conversion of monophenols into catechols via tyrosinase, where films form on surfaces via covalent and coordination cross‐linking. The resulting coatings are robust, functional (e.g., in protective coatings, biological imaging, and enzymatic catalysis), and versatile for diverse secondary surface‐confined reactions (e.g., biomineralization, metal ion chelation, and N‐hydroxysuccinimide conjugation).

The manipulation of interfacial properties has broad implications for the development of high‐performance coatings. Metal–phenolic networks (MPNs) are an emerging class of responsive, adherent materials. Herein, host–guest chemistry is integrated with MPNs to modulate their surface chemistry and interfacial properties. Macrocyclic cyclodextrins (host) are conjugated to catechol or galloyl groups and subsequently used as components for the assembly of functional MPNs. The assembled cyclodextrin‐based MPNs are highly permeable (even to high molecular weight polymers: 250–500 kDa), yet they specifically and noncovalently interact with various functional guests (including small molecules, polymers, and carbon nanomaterials), allowing for modular and reversible control over interfacial properties. Specifically, by using either hydrophobic or hydrophilic guest molecules, the wettability of the MPNs can be readily tuned between superrepellency (>150°) and superwetting (ca. 0°).

There is a need for improved nanomaterials to simultaneously target cancer cells and avoid non‐specific clearance by phagocytes. An ellipsoidal polymersome system is developed with a unique tunable size and shape property. These particles are functionalized with in‐house phage‐display cell‐targeting peptide to target a medulloblastoma cell line in vitro. Particle association with medulloblastoma cells is modulated by tuning the peptide ligand density on the particles. These polymersomes has low levels of association with primary human blood phagocytes. The stealth properties of the polymersomes are further improved by including the peptide targeting moiety, an effect that is likely driven by the peptide protecting the particles from binding blood plasma proteins. Overall, this ellipsoidal polymersome system provides a promising platform to explore tumor cell targeting in vivo.

Minimizing the interaction of nanomedicines with the mononuclear phagocytic system (MPS) is a critical challenge for their clinical translation. Conjugating polyethylene glycol (PEG) to nanomedicines is regarded as an effective approach to reducing the sequestration of nanomedicines by the MPS. However, recent concerns about the immunogenicity of PEG highlight the demand of alternative low-fouling polymers as innovative coating materials for nanoparticles. Herein, a highly hydrophilic sulfoxide-containing polymer-poly(2-(methylsulfinyl)ethyl acrylate) (PMSEA)-is used for the surface coating of iron oxide nanoparticles (IONPs). It is found that the PMSEA polymer coated IONPs have a more hydrophilic surface than their PEGylated counterparts, and demonstrate remarkably reduced macrophage cellular uptake and much less association with human plasma proteins. In vivo study of biodistribution and pharmacokinetics further reveals a much-extended blood circulation (≈2.5 times longer in terms of elimination half-life t 1/2) and reduced accumulation (approximately two times less) in the organs such as the liver and spleen for IONPs coated by PMSEA than those by PEG. It is envisaged that the highly hydrophilic sulfoxide-containing polymers have huge potential to be employed as an advantageous alternative to PEG for the surface functionalization of a variety of nanoparticles for long circulation and improved delivery.

Engineering reactive and functional nanostructured surfaces is important for enhancing the sensitivity and versatility of biosensors and microreactors. For example, the assembly of hybrid inorganic–organic porous microparticles on surfaces may provide a catalytic microenvironment for a wide range of reactions. Herein, the synthesis of catalytically active porous dextran sulfate–copper phosphate hybrid microparticles by a facile and rapid crystallization process in aqueous solution is reported. The sulfated polysaccharide enables control over the size and hierarchical morphology of the hybrid microparticles, as well as their assembly into stable macroporous coatings. The engineered microparticle coatings display intrinsic nonenzymatic peroxidase‐like catalytic activity when employed as a platform for the detection of hydrogen peroxide. Pairing of the microparticle coating with glucose oxidase affords a hybrid platform that is employed as a glucose sensor for monitoring physiological concentrations of a given analyte via a hybrid enzymatic/nonenzymatic cascade reaction. This work presents a strategy for the assembly of hybrid porous microparticles into enzyme‐mimicking surfaces for copper‐based catalysis and biochemical analyte sensing.

Biological nanoparticles found in living systems possess distinct molecular architectures and diverse functions. Glycogen is a unique biological polysaccharide nanoparticle fabricated by nature through a bottom‐up approach. The biocatalytic synthesis of glycogen has evolved over time to form a nanometer‐sized dendrimer‐like structure (20–150 nm) with a highly branched surface and a dense core. This makes glycogen markedly different from other natural linear or branched polysaccharides and particularly attractive as a platform for biomedical applications. Glycogen is inherently biodegradable, nontoxic, and can be functionalized with diverse surface and internal motifs for enhanced biofunctional properties. Recently, there has been growing interest in glycogen as a natural alternative to synthetic polymers and nanoparticles in a range of applications. Herein, the recent literature on glycogen in the material‐based sciences, including its use as a constituent in biodegradable hydrogels and fibers, drug delivery vectors, tumor targeting and penetrating nanoparticles, immunomodulators, vaccine adjuvants, and contrast agents, is reviewed. The various methods of chemical functionalization and physical assembly of glycogen nanoparticles into multicomponent nanodevices, which advance glycogen toward a functional therapeutic nanoparticle from nature and back again, are discussed in detail.

Functional coatings are of considerable interest because of their fundamental implications for interfacial assembly and promise for numerous applications. Universally adherent materials have recently emerged as versatile functional coatings; however, such coatings are generally limited to catechol, (ortho‐diphenol)‐containing molecules, as building blocks. Here, we report a facile, biofriendly enzyme‐mediated strategy for assembling a wide range of molecules (e.g., 14 representative molecules in this study) that do not natively have catechol moieties, including small molecules, peptides, and proteins, on various surfaces, while preserving the molecule's inherent function, such as catalysis (≈80 % retention of enzymatic activity for trypsin). Assembly is achieved by in situ conversion of monophenols into catechols via tyrosinase, where films form on surfaces via covalent and coordination cross‐linking. The resulting coatings are robust, functional (e.g., in protective coatings, biological imaging, and enzymatic catalysis), and versatile for diverse secondary surface‐confined reactions (e.g., biomineralization, metal ion chelation, and N‐hydroxysuccinimide conjugation).

The adsorption of biomolecules onto nanomaterials can alter the performance of the nanomaterials in vitro and in vivo. Recent studies have primarily focused on the protein “corona”, formed upon adsorption of proteins onto nanoparticles in biological fluids, which can change the biological fate of the nanoparticles. Conversely, interactions between nanomaterials and other classes of biomolecules namely, lipids, nucleic acids, and polysaccharides have received less attention despite their important roles in biology. A possible reason is the challenge associated with investigating biomolecule interactions with nanomaterials using current technologies. Herein, a protocol is developed for studying bio–nano interactions by depositing four classes of biomolecules (proteins, lipids, nucleic acids, and polysaccharides) and complex biological media (blood) onto planar substrates, followed by exposure to metal–phenolic network (MPN) complexes. The MPNs preferentially interact with the biomolecule over the inorganic substrate (glass), highlighting that patterned biomolecules can be used to engineer patterned MPNs. Subsequent formation of silver nanoparticles on the MPN films maintains the patterns and endows the films with unique reflectance and fluorescence properties, enabling visualization of latent fingerprints (i.e., invisible residual biomolecule patterns). This study demonstrates the potential complexity of the biomolecule corona as all classes of biomolecules can adsorb onto MPN-based nanomaterials.

Low-fouling or "stealth" particles composed of poly(ethylene glycol) (PEG) display a striking ability to evade phagocytic cell uptake. However, functionalizing them for specific targeting is challenging. To address this challenge, stealth PEG particles prepared by a mesoporous silica templating method are functionalized with bispecific antibodies (BsAbs) to obtain PEG-BsAb particles via a one-step binding strategy for cell and tumor targeting. The dual specificity of the BsAbs-one arm binds to the PEG particles while the other targets a cell antigen (epidermal growth factor receptor, EGFR)-is exploited to modulate the number of targeting ligands per particle. Increasing the BsAb incubation concentration increases the amount of BsAb tethered to the PEG particles and enhances targeting and internalization into breast cancer cells overexpressing EGFR. The degree of BsAb functionalization does not significantly reduce the stealth properties of the PEG particles ex vivo, as assessed by their interactions with primary human blood granulocytes and monocytes. Although increasing the BsAb amount on PEG particles does not lead to the expected improvement in tumor accumulation in vivo, BsAb functionalization facilitates tumor cell uptake of PEG particles. This work highlights strategies to balance evading nonspecific clearance pathways, while improving tumor targeting and accumulation.

Phenolische Materialien sind seit langem für ihre Verwendung in Farbtinten, in Holzbeschichtungen und zur Ledergerbung bekannt. In letzter Zeit ist jedoch ein wachsendes Interesse an der Entwicklung moderner Werkstoffe aus phenolischen Bausteinen zu verzeichnen. Die intrinsischen Eigenschaften von phenolischen Verbindungen, wie Metallchelat‐Bildung, Wasserstoffbrücken, pH‐Ansprechverhalten, Redoxpotentiale, Radikalfänger, Polymerisation und Lichtabsorption, haben sie zu einer eigenständigen Klasse von Strukturelementen für die Synthese von funktionellen Materialien gemacht. Aus Phenolverbindungen hergestellte Materialien behalten viele ihrer nützlichen Eigenschaften, oft mit synergistischen Effekten bei Anwendungen, die von der Katalyse bis zur Biomedizin reichen. Dieser Aufsatz gibt einen Überblick über die verschiedenen funktionellen Materialien, die aus natürlichen und synthetischen phenolischen Bausteinen hergestellt werden können, und über ihre Anwendungen.

Over the past few decades, nanoengineered particles have gained increasing interest for applications in the biomedical realm, including diagnosis, imaging, and therapy. When functionalized with targeting ligands, these particles have the potential to interact with specific cells and tissues, and accumulate at desired target sites, reducing side effects and improve overall efficacy in applications such as vaccination and drug delivery. However, when targeted particles enter a complex biological environment, the adsorption of biomolecules and the formation of a surface coating (e.g., a protein corona) changes the properties of the carriers and can render their behavior unpredictable. For this reason, it is of importance to consider the potential challenges imposed by the biological environment at the early stages of particle design. This review describes parameters that affect the targeting ability of particulate drug carriers, with an emphasis on the effect of the protein corona. We highlight strategies for exploiting the protein corona to improve the targeting ability of particles. Finally, we provide suggestions for complementing current in vitro assays used for the evaluation of targeting and carrier efficacy with new and emerging techniques (e.g., 3D models and flow-based technologies) to advance fundamental understanding in bio-nano science and to accelerate the development of targeted particles for biomedical applications.

The synthesis of metal nanoparticle (NP)-coated textiles (nanotextiles) is achieved by a dipping process in water without toxic chemicals or complicated synthetic procedures. By taking advantage of the unique nature of tannic acid, metal-phenolic network-coated textiles serve as reducing and stabilizing sites for the generation of metal nanoparticles of controllable size. The textiles can be decorated with various metal nanoparticles, including palladium, silver, or gold, and exhibit properties derived from the presence of the metal nanoparticles, for example, catalytic activity in water (>96% over five cycles using palladium nanoparticles) and antibacterial activity against Gram-negative bacteria (inhibition of Escherichia coli using silver nanoparticles) that outperforms a commercial bandage. The reported strategy offers opportunities for the development of hybrid nanomaterials that may have application in fields outside of catalysis and antimicrobials, such as sensing and smart clothing.

Therapeutic nanoparticles hold clinical promise for cancer treatment by avoiding limitations of conventional pharmaceuticals. Herein, a facile and rapid method is introduced to assemble poly(ethylene glycol) (PEG)-modified Pt prodrug nanocomplexes through metal-polyphenol complexation and combined with emulsification, which results in ≈100 nm diameter nanoparticles (PtP NPs) that exhibit high drug loading (0.15 fg Pt per nanoparticle) and low fouling properties. The PtP NPs are characterized for potential use as cancer therapeutics. Mass cytometry is used to quantify uptake of the nanoparticles and the drug concentration in individual cells in vitro. The PtP NPs have long circulation times, with an elimination half-life of ≈18 h in healthy mice. The in vivo antitumor activity of the PtP NPs is systematically investigated in a human prostate cancer xenograft mouse model. Mice treated with the PtP NPs demonstrate four times better inhibition of tumor growth than either free prodrug or cisplatin. This study presents a promising strategy to prepare therapeutic nanoparticles for biomedical applications.

We report the synthesis of chemically asymmetric silica nanobottles (NBs) with a hydrophobic exterior surface (capped with 3‐chloropropyl groups) and a hydrophilic interior surface for spatially selective cargo loading, and for application as nanoreactors and nanomotors. The silica NBs, which have a “flask bottle” shape with an average diameter of 350 nm and an opening of ca. 100 nm, are prepared by anisotropic sol–gel growth in a water/n‐pentanol emulsion. Due to their chemically asymmetric properties, nanoparticles (NPs) with hydrophilic or hydrophobic surface properties can be selectively loaded inside the NBs or on the outside of the NBs, respectively. A high‐performance nanomotor is constructed by selectively loading catalytically active hydrophilic Pt NPs inside the NBs. It is also demonstrated that these NBs can be used as vessels for various reactions, such as the in situ synthesis of Au NPs, and using Au NP‐loaded NBs as nanoreactors for catalytic reactions.

K. Liang, P. Falcaro, and co-workers report on page 7293 that metal-organic frameworks (MOFs) can be replicated in a biomimetic fashion from protein patterns on a surface. Bendable, fluorescent MOF patterns are formed with micrometer resolution under ambient conditions. This technique is used to grow MOF patterns from fingerprint residue in 30 s with high fidelity. This technique is not only relevant for crime-scene investigation, but also for biomedical applications.

Novel membranes are fabricated for use in desalination and water purification applications by F. Caruso, S. E. Kentish, and co-workers, described on page 2791. The crosslinked polyelectrolyte multilayer membranes are synthesized on a porous polysulfone support within aqueous media and are crosslinked with glutaraldehyde. This leads to NaCl rejections of up to 97%. The incorporation of a highly sulfonated polysulfone polyanion results in outstanding chlorine resistance.

Dual-responsive boronate-phenolic network (BPN) capsules are fabricated by the complexation of phenylborate and phenolic materials. The BPN capsules are stable in the presence of competing carbohydrates, but dissociate at acidic pH or in the presence of competing cis-diols at physiological pH. This engineered capsule system provides a platform for a wide range of biological and biomedical applications.

Polymer microcapsules are of particular interest for applications including self-healing coatings, catalysis, bioreactions, sensing, and drug delivery. The primary way that polymer capsules can exhibit functionality relevant to these diverse fields is through the incorporation of functional cargo in the capsule cavity or wall. Diverse functional and therapeutic cargo can be loaded into polymer capsules with ease using polymer-stabilized calcium carbonate (CaCO3) particles. A variety of examples are demonstrated, including 15 types of cargo, yielding a toolbox with effectively 500+ variations. This process uses no harsh reagents and can take less than 30 min to prepare, load, coat, and form the hollow capsules. For these reasons, it is expected that the technique will play a crucial role across scientific studies in numerous fields.

The chemical absorption of CO2 into a monoethanolamine solvent is currently the most widely accepted commercial approach to carbon dioxide capture. However, the subsequent desorption of CO2 from the solvents is extremely energy intensive. Alternative solvents are more energy efficient, but their slow reaction kinetics in the CO2 absorption step limits application. The use of a carbonic anhydrase (CA) enzyme as a reaction promoter can potentially overcome this obstacle. Native, engineered and artificial CA enzymes have been investigated for this application. Immobilization of the enzyme within the gas absorber or in a membrane format can increase enzyme stability and avoid thermal denaturation in the stripper. However, immobilization is only effective if the mass transfer of carbon dioxide through the liquid phase to reach the immobilization substrate does not become rate controlling. Further research should also consider the process economics of large-scale enzyme production and the long-term performance of the enzyme under real flue gas conditions.

Mesoporous silica supraparticles (MS-SPs) self-assembled from mesoporous silica nanoparticles are reported on page 4244 by F. Caruso and co-workers. The MS-SPs are effective carriers for the sustained delivery of brain-derived neurotrophic factor. Animal studies show that the MS-SPs can be implanted into the cochlea and deliver neurotrophins to prevent the progressive loss of the auditory neurons that normally occurs with deafness.

A new class of polymer capsules with an in-built endocytic pH-coupled fluorescence switch is reported. These capsules display reversible "on/off" fluorescence in response to cellular pH variations. Using this system, the high-throughput quantification between surface-bound and internalized capsules is demonstrated. This system allows a fundamental study of the interaction between nanoengineered materials and biological systems at a cellular level.

Mesoporous silica supraparticles (MS-SPs) are prepared via self-assembly of mesoporous silica nanoparticles under capillary force action in confined droplets. The MS-SPs are effective carriers for sustained drug delivery. Animal studies show that these particles are suitable for chronic intracochlear implantation, and neurotrophins released from the MS-SPs can efficiently rescue primary auditory neurons in an in vivo sensorineural hearing loss model.

Nanostructured particulate materials are expected to revolutionize diagnostics and the delivery of therapeutics for healthcare. To date, chemistry-derived solutions have been the major focus in the design of materials to control interactions with biological systems. Only recently has control over a new set of physical parameters, including size, shape, and rigidity, been explored to optimize the biological response and the in vivo performance of nanoengineered delivery vectors. This Review highlights the methods used to manipulate the physical properties of particles and the relevance of these physical properties to cellular and circulatory interactions. Finally, the importance of future work to synergistically tailor both physical and chemical properties of particulate materials is discussed, with the aim of improving control over particle interactions in the biological domain.