Current Opinion in Colloid & Interface Science最新文献

The increasing number of multidrug-resistant bacteria is a growing threat to global public health. Contaminated surfaces pose a major problem in the spreading of these superbugs and are a source of bacterial infections that are difficult to treat. Surfaces that repel bacteria or impede biofilms where bacteria are inaccessible to conventional drugs are in great demand for medical and technological applications. Immense multi-disciplinary efforts are being made to develop biocompatible, long-lasting, scalable, and cost-effective antimicrobial surfaces. Here, we highlight emerging strategies that involve harnessing natural and synthetic polymeric nanoassemblies that are antimicrobial either by themselves or through association with antimicrobial compounds to engineer antimicrobial surfaces. Our aim is to move underexplored nanoassemblies into the limelight. Based on their chemical versatility, structural tenability, and orthogonal activity of associated molecules and structures, the nanoassemblies discussed overcome cytotoxicity, non-biodegradability, and short-term antibacterial activity to offer novel surfaces with improved antibacterial and antibiofilm prospects.

Infections can lead to severe health issues, even death. Surfaces, such as those of biomedical devices, implants, textiles, tables and doorknobs, play a crucial role as carriers for pathogens to migrate, attach and proliferate. Implementing surfaces with antimicrobial properties offers a reliable and long-lasting approach to combat surface transmission of germs, minimize microbial colonization, and reduce infections. In this review, we present recent advancements in antimicrobial surfaces, categorized into four groups based on their action mechanisms: antifouling, bactericidal, antifouling and bactericidal, and dynamic or stimuli-responsive surfaces. The work highlights the fabrication processes and properties of each category, along with discussing their structure-performance relationships. Special attention is given to various anchoring strategies involving tunable molecular interactions. The review also introduces relevant biomedical applications.

Lipid nanoparticles (LNPs) are the most versatile and successful gene delivery systems, notably highlighted by their use in vaccines against COVID-19. LNPs have a well-defined core–shell structure, each region with its own distinctive compositions, suited for a wide range of in vivo delivery applications. Here, we discuss how a detailed knowledge of LNP structure can guide LNP formulation to improve the efficiency of delivery of their nucleic acid payload. Perspectives are detailed on how LNP structural design can guide more efficient nucleic acid transfection. Views on key physical characterization techniques needed for such developments are outlined including opinions on biophysical approaches both correlating structure with functionality in biological fluids and improving their ability to escape the endosome and deliver they payload.

Colloidal properties of viruses largely define the stability, transport, and host interactions of viruses. Despite attempts to unravel the correlation between colloidal virus properties and their interactions outside and inside their host, an in-depth understanding is still missing. This knowledge gap is, to a great extent, caused by challenges associated with the capacity to probe these properties experimentally; thus, great efforts are being invested in developing new approaches or transforming existing ones to characterize the physical-chemical, i.e., colloidal, properties of viruses. Understanding the correlation between these properties and virus interactions is not only important from a scientific point of view but will also hopefully inspire the design of novel viral vectors and virus-like particles for biomedical applications. In this review, we cover the recent experimental advances in characterizing the colloidal properties of viruses with particular attention to virus hydrophobicity, genetic load, nanomechanical properties, and surface interaction forces with host cells.

Throughout a lifetime, articular joints experience many loading cycles and are prone to mechanical degradation. To safeguard the cartilage in these joints, the synovial fluid acts as a natural lubricant. However, degenerative joint diseases, like osteoarthritis, alter the composition of synovial fluid, diminishing its protective properties. In such cases, exogenous lubricants or viscosupplements can be injected to enhance the compromised synovial fluid's function. Scientists are now developing next-generation viscosupplements, based on hyaluronic acid (HA), that can better bind to and adhere to cartilage. Additionally, non-HA-based viscosupplements offer benefits over HA-based ones, as they possess more intricate molecular architectures, such as dendrimer or bottlebrush-like structures. These viscosupplements draw inspiration from natural molecules present in synovial fluid, providing them with a distinct advantage.

Due to the high density of human populations within enclosed spaces, respiratory viruses are mainly transmitted via airborne aerosols; however, they can also be transmitted via indirect contact when a respiratory droplet containing a viral load contaminates a smooth surface, on which some viruses have long survivability. In this perspective, we outline recent developments of antiviral surfaces to combat the surface transmission of viruses. Numerous technologies already exist for the development of antibacterial surfaces that have the potential to be extended toward the development of antiviral surfaces. We overview the potential to utilise nanostructured surfaces for the physical inactivation of virus particles. However, there remains a limited number of suitable nanofabrication approaches and a lack of understanding of the nature of efficient virucidal surfaces.

The confinement of substrates inside the cavity of self-assembled capsules makes it possible to effectively catalyze organic reactions in a way that is analogous to how enzymes work in biological systems. Due to steric constraints, solvent exclusion, intermediates stabilization, and conformational control of substrates, chemical reactions taking place in a confined space may exhibit unique processes. As a result, the fundamental rules of organic reactivity are frequently broken. The hexameric capsule C_R, an intriguing supramolecular assembly formed by six resorcinarene 1 macrocycles and eight water molecules, is the subject of this review. This assembly has proven to be effective at catalyzing several chemical reactions by controlling reactivity and selectivity in its confined space.

Nanoarchitectonics, as a post-nanotechnology concept, is the methodology for constructing functional materials from nano-units, which bridges the gap between nanotechnology and materials science. The research accomplishes advocating nanoarchitectonics has increased dramatically as overviewed in the initial part of this review. Then, as socially impactful subjects, we exemplify nanoarchitectonics research for bacterial infections according to classifications featured with molecular tools, interfaces, and hierarchically structured materials. In particular, this review article discusses namely three kinds of antibacterial strategies: (i) new antimicrobial agents and therapeutic modalities based on nanoarchitectonics present high bactericidal efficacy against methicillin-resistant Staphylococcus aureus; (ii) antimicrobial nanoarchitectonics structures are integrated into the surface of medical devices to detach or kill approaching bacteria; (iii) the nanoarchitectonics hydrogels act as antimicrobial reservoirs to produce sustained-release antimicrobial agents for long-lasting bacterial killing.

Non-healing wounds cause hundreds of thousands of deaths every year, and result in large costs for society. A key reason for this is the prevalence of challenging bacterial infections, which may dramatically hinder wound healing. With resistance development among bacteria against antibiotics, this situation has deteriorated during the last couple of decades, pointing to an urgent need for new wound treatments. In particular, this applies to wound dressings able to combat bacterial infection locally in wounds and impaired skin, including those formed by bacteria resistant to conventional antibiotics. Within this context, antimicrobial peptides (AMPs) are currently receiving intense interest. AMPs are amphiphilic peptides, frequently net positively charged, and with a sizable fraction of hydrophobic amino acids. Through destabilization of bacterial membranes, neutralization of inflammatory lipopolysaccharides, and other mechanisms, AMPs can be designed for potent antimicrobial effects, also against antibiotics-resistant strains, and to provide immunomodulatory effects while simultaneously displaying low toxicity. While considerable attention has been placed on AMP optimization and clarification of their mode(s)-of-action, much less attention has been paid on efficient AMP delivery. Considering that AMPs are large molecules, net positively charged, amphiphilic, and susceptible to infection-mediated proteolytic degradation, efficient in vivo delivery of such peptides is, however, challenging and delivery systems needed for the realization of AMP-based therapeutics. In the present work, recent developments regarding AMP delivery systems for treatment of wounds and skin infections are discussed, with the aim to link results from physicochemical studies on, e.g., peptide loading/release, membrane interactions, and self-assembly, with those on the biological functional performance of AMP delivery systems in terms of antimicrobial effects, cell toxicity, inflammation, and wound healing.