Biomolecular coronas provide the biological identity of nanosized materials

Recent advance in preparation of lignin nanoparticles and their medical applications: A review

BACKGROUND

Lignin has attracted a lot of attention because it is non-toxic, renewable and biodegradable. Lignin nanoparticles (LNPs) have high specific surface area and specific surface charges. It provides LNPs with good antibacterial and antioxidant properties. LNPs preparation has become clear, however, the application remains in the early stages.

PURPOSE

A review centric research has been conducted, reviewing existing literature to accomplish a basic understanding of the medical applications of LNPs.

METHODS

Initially, we extensively counseled the heterogeneity of lignin from various sources. The size and morphology of LNPs from different preparation process were then discussed. Subsequently, we focused on the potential medical applications of LNPs, including drug delivery, wound healing, tissue engineering, and antibacterial agents. Lastly, we explained the significance of LNPs in terms of antibacterial, antioxidant and biocompatibility, especially highlighting the need for an integrated framework to understand a diverse range of medical applications of LNPs.

RESULTS

We outlined the chemical structure of different type of lignin, and highlighted the advanced methods for lignin nanoparticles preparation. Moreover, we provided an in-depth review of the potential applications of lignin nanoparticles in various medical fields, especially in drug carriers, wound dressings, tissue engineering components, and antimicrobial agents.

CONCLUSION

This review provides a detailed overview on the current state and progression of lignin nanoparticles for medical applications.

Effect of Nanoparticle Curvature on Its Interaction with Serum Proteins

The size or the curvature of nanoparticles (NPs) plays an important role in regulating the composition of the protein corona. However, the molecular mechanisms of how curvature affects the interaction of NPs with serum proteins still remain elusive. In this study, we employ all-atom molecular dynamics simulations to investigate the interactions between two typical serum proteins and PEGylated Au NPs with three different surface curvatures (0, 0.1, and 0.5 nm-1, respectively). The results show that for proteins with a regular shape, the binding strength between the serum protein and Au NPs decreases with increasing curvature. For irregularly shaped proteins with noticeable grooves, the binding strength between the protein and Au NPs does not change obviously with increasing curvature in the cases of smaller curvature. However, as the curvature continues to increase, Au NPs may act as ligands firmly adsorbed in the protein grooves, significantly enhancing the binding strength. Overall, our findings suggest that the impact of NP curvature on protein adsorption may be nonmonotonic, which may provide useful guidelines for better design of functionalized NPs in biomedical applications.

Concepts and Approaches to Reduce or Avoid Protein Corona Formation on Nanoparticles: Challenges and Opportunities

This review describes the formation of a protein corona (or its absence) on different classes of nanoparticles, its basic principles, and its consequences for nanomedicine. For this purpose, it describes general concepts to control (guide/minimize) the interaction between artificial nanoparticles and plasma proteins to reduce protein corona formation. Thereafter, methods for the qualitative or quantitative determination of protein corona formation are presented, as well as the properties of nanoparticle surfaces, which are relevant for protein corona prevention (or formation). Thereby especially the role of grafting density of hydrophilic polymers on the surface of the nanoparticle is discussed to prevent the formation of a protein corona. In this context also the potential of detergents (surfactants) for a temporary modification as well as grafting-to and grafting-from approaches for a permanent modification of the surface are discussed. The review concludes by highlighting several promising avenues. This includes (i) the use of nanoparticles without protein corona for active targeting, (ii) the use of synthetic nanoparticles without protein corona formation to address the immune system, (iii) the recollection of nanoparticles with a defined protein corona after in vivo application to sample the blood proteome and (iv) further concepts to reduce protein corona formation.

Preadsorbed Chymotrypsin Modulated the Composition of Protein Corona and Immunological Response

It is well-known that proteins after administration into biological environments adsorb on the surface of nanoparticles (NPs). The biological identity could be determined by protein corona, but whether and how the preadsorbed molecules impact the composition of the corona and immunological response have rarely been reported. Here, the effects of preadsorbed chymotrypsin (Chy) on forming protein corona and subsequent immunological response are reported. We find that preadsorbed Chy on the surface of AuNPs results in a protein corona with enriched immunoglobulins and reduced human serum albumin protein, which further affect the polarization of macrophages into specific phenotypes. Our study suggests that the protein surrounding the nanoparticles could affect the protein corona and immunological response, which may direct the preparation of multifunctional nanomedicine for future studies.

Therapeutics of the future: Navigating the pitfalls of extracellular vesicles research from an osteoarthritis perspective

Extracellular vesicles have gained wide momentum as potential therapeutics for osteoarthritis, a highly prevalent chronic disease that still lacks an approved treatment. The membrane-bound vesicles are secreted by all cells carrying different cargos that can serve as both disease biomarkers and disease modifiers. Nonetheless, despite a significant peak in research regarding EVs as OA therapeutics, clinical implementation seems distant. In addition to scalability and standardization challenges, researchers often omit to focus on and consider the proper tropism of the vesicles, the practicality and relevance of their source, their low native therapeutic efficacy, and whether they address the disease as a whole. These considerations are necessary to better understand EVs in a clinical light and have been comprehensively discussed and ultimately summarized in this review into a conceptualized framework termed the nanodiamond concept. Future perspectives are also discussed, and alternatives are presented to address some of the challenges and concerns.

Possibilities and limitations of solution-state NMR spectroscopy to analyze the ligand shell of ultrasmall metal nanoparticles

Ultrasmall nanoparticles have a diameter between 1 and 3 nm at the border between nanoparticles and large molecules. Usually, their core consists of a metal, and the shell of a capping ligand with sulfur or phosphorus as binding atoms. While the core structure can be probed by electron microscopy, electron and powder diffraction, and single-crystal structure analysis for atom-sharp clusters, it is more difficult to analyze the ligand shell. In contrast to larger nanoparticles, ultrasmall nanoparticles cause only a moderate distortion of the NMR signal, making NMR spectroscopy a qualitative as well as a quantitative probe to assess the nature of the ligand shell. The application of isotope-labelled ligands and of two-dimensional NMR techniques can give deeper insight into ligand-nanoparticle interactions. Applications of one- and two-dimensional NMR spectroscopy to analyze ultrasmall nanoparticles are presented with suitable examples, including a critical discussion of the limitations of NMR spectroscopy on nanoparticles.

Highly elastic, fatigue-resistant, antibacterial, conductive, and nanocellulose-enhanced hydrogels with selenium nanoparticles loading as strain sensors

The fabrication of highly elastic, fatigue-resistant and conductive hydrogels with antibacterial properties is highly desirable in the field of wearable devices. However, it remains challenging to simultaneously realize the above properties within one hydrogel without compromising excellent sensing ability. Herein, we fabricated a highly elastic, fatigue-resistant, conductive, antibacterial and cellulose nanocrystal (CNC) enhanced hydrogel as a sensitive strain sensor by the synergistic effect of biosynthesized selenium nanoparticles (BioSeNPs), MXene and nanocellulose. The structure and potential mechanism to generate biologically synthesized SeNPs (BioSeNPs) were systematically investigated, and the role of protease A (PrA) in enhancing the adsorption between proteins and SeNPs was demonstrated. Additionally, owing to the incorporation of BioSeNPs, CNC and MXene, the synthesized hydrogels showed high elasticity, excellent fatigue resistance and antibacterial properties. More importantly, the sensitivity of hydrogels determined by the gauge factor was as high as 6.24 when a high strain was applied (400-700 %). This study provides a new horizon to synthesize high-performance antibacterial and conductive hydrogels for soft electronics applications.

A Nanoplasmonic Assay for Point-of-Care Detection of Mannose-Binding Lectin in Human Serum

Mannose-binding lectin (MBL) activates the complement system lectin pathway and subsequent inflammatory mechanisms. The incidence and outcome of many human diseases, such as brain ischemia and infections, are associated with and influenced by the activity and serum concentrations of MBL in body fluids. To quantify MBL levels, tests based on ELISA are used, requiring several incubation and washing steps and lengthy turnaround times. Here, we aimed to develop a nanoplasmonic assay for direct MBL detection in human serum at the point of care. Our assay is based on gold nanorods (GNRs) functionalized with mannose (Man-GNRs) via an amphiphilic linker. We experimentally determined the effective amount of sugar linked to the nanorods' surface, resulting in an approximate grafting density of 4 molecules per nm2, and an average number of 11 to 13 MBL molecules binding to a single nanoparticle. The optimal Man-GNRs concentration to achieve the highest sensitivity in MBL detection was 15 μg·mL-1. The specificity of the assay for MBL detection both in simple buffer and in complex pooled human sera was confirmed. Our label-free biosensor is able to detect MBL concentrations as low as 160 ng·mL-1 within 15 min directly in human serum via a one-step reaction and by using a microplate reader. Hence, it forms the basis for a fast, noninvasive, point-of-care assay for diagnostic indications and monitoring of disease and therapy.

A Review on Investigating the Interactions between Nanoparticles and the Pulmonary Surfactant Monolayer with Coarse-Grained Molecular Dynamics Method

Pulmonary drug delivery has garnered significant attention due to its targeted local lung action, minimal toxic side effects, and high drug utilization. However, the physicochemical properties of inhaled nanoparticles (NPs) used as drug carriers can influence their interactions with the pulmonary surfactant (PS) monolayer, potentially altering the fate of the NPs and impairing the biophysical function of the PS monolayer. Thus, the objective of this review is to summarize how the physicochemical properties of NPs affect their interactions with the PS monolayer. Initially, the definition and properties of NPs, as well as the composition and characteristics of the PS monolayer, are introduced. Subsequently, the coarse-grained molecular dynamics (CGMD) simulation method for studying the interactions between NPs and the PS monolayer is presented. Finally, the implications of the hydrophobicity, size, shape, surface charge, surface modification, and aggregation of NPs on their interactions with the PS monolayer and on the composition of biomolecular corona are discussed. In conclusion, gaining a deeper understanding of the effects of the physicochemical properties of NPs on their interactions with the PS monolayer will contribute to the development of safer and more effective nanomedicines for pulmonary drug delivery.

Surface property and in vitro toxicity effect of insoluble particles given by protein corona: Implication for PM cytotoxicity assessment

In vitro toxicological assessment helps explore key fractions of particulate matter (PM) in association with the toxic mechanism. Previous studies mainly discussed the toxicity effects of the water-soluble and organic-soluble fractions of PM. However, the toxicity of insoluble fractions is relatively poorly understood, and the adsorption of proteins is rarely considered. In this work, the formation of protein corona on the surface of insoluble particles during incubation in a culture medium was investigated. It was found that highly abundant proteins in fetal bovine serum were the main components of the protein corona. The adsorbed proteins increased the dispersion stability of insoluble particles. Meanwhile, the leaching concentrations of some metal elements (e.g., Cu, Zn, and Pb) from PM increased in the presence of proteins. The toxicity effects and potential mechanisms of the PM insoluble particle-protein corona complex on macrophage cells RAW264.7 were discussed. The results revealed that the PM insoluble particle-protein corona complex could influence the phagosome pathway in RAW264.7 cells. Thus, it promoted the intracellular reactive oxygen species generation and induced a greater degree of cell differentiation, significantly altering cell morphology. Consequently, this work sheds new light on the combination of insoluble particles and protein corona in terms of PM cytotoxicity assessment.

Design of PD-L1-Targeted Lipid Nanoparticles to Turn on PTEN for Efficient Cancer Therapy

Lipid nanoparticles (LNPs) exhibit remarkable mRNA delivery efficiency, yet their majority accumulate in the liver or spleen after injection. Tissue-specific mRNA delivery can be achieved through modulating LNP properties, such as tuning PEGylation or varying lipid components systematically. In this paper, a streamlined method is used for incorporating tumor-targeting peptides into the LNPs; the programmed death ligand 1 (PD-L1) binding peptides are conjugated to PEGylated lipids via a copper-free click reaction, and directly incorporated into the LNP composition (Pep LNPs). Notably, Pep LNPs display robust interaction with PD-L1 proteins, which leads to the uptake of LNPs into PD-L1 overexpressing cancer cells both in vitro and in vivo. To evaluate anticancer immunotherapy mediated by restoring tumor suppressor, mRNA encoding phosphatase and tensin homolog (PTEN) is delivered via Pep LNPs to PTEN-deficient triple-negative breast cancers (TNBCs). Pep LNPs loaded with PTEN mRNA specifically promotes autophagy-mediated immunogenic cell death in 4T1 tumors, resulting in effective anticancer immune responses. This study highlights the potential of tumor-targeted LNPs for mRNA-based cancer therapy.

Protein Binding Leads to Reduced Stability and Solvated Disorder in the Polystyrene Nanoparticle Corona

Understanding the conformation of proteins in the nanoparticle corona has important implications in how organisms respond to nanoparticle-based drugs. These proteins coat the nanoparticle surface, and their properties will influence the nanoparticle's interaction with cell targets and the immune system. While some coronas are thought to be disordered, two key unanswered questions are the degree of disorder and solvent accessibility. Here, a model is developed for protein corona disorder in polystyrene nanoparticles of varying size. For two different proteins, it is found that binding affinity decreases as nanoparticle size increases. The stoichiometry of binding, along with changes in the hydrodynamic size, supports a highly solvated, disordered protein corona anchored at a small number of attachment sites. The scaling of the stoichiometry versus nanoparticle size is consistent with disordered polymer dimensions. Moreover, it is found that proteins are destabilized less in the presence of larger nanoparticles, and hydrophobic exposure decreases at lower curvatures. The observations hold for proteins on flat polystyrene surfaces, which have the lowest hydrophobic exposure. The model provides an explanation for previous observations of increased amyloid fibrillation rates in the presence of larger nanoparticles, and it may rationalize how cell receptors can recognize protein disorder in therapeutic nanoparticles.

The biomolecular corona of nanomedicines: effects on nanomedicine outcomes and emerging opportunities

Upon administration, nanomedicines adsorb a corona of endogenous biomolecules on their surface, which can affect nanomedicine interactions with cells, targeting, and efficacy. While strategies to reduce protein binding are available, the high selectivity of the adsorbed corona is enabling novel applications, such as for biomarker discovery and rare protein identification. Additionally, the adsorbed molecules can promote interactions with specific cell receptors, thus conferring the nanomedicine new endogenous targeting capabilities. This has been reported for Onpattro, a lipid nanoparticle targeting the hepatocytes via apolipoproteins in its corona. Recently, selective organ-targeting (SORT) nanoparticles have been proposed, which exploit corona-mediated interactions to deliver nanoparticles outside the liver. Strategies for corona seeding and corona engineering are emerging to increase the selectivity of similar endogenous targeting mechanisms.

Semiconducting polymer dots for multifunctional integrated nanomedicine carriers

The expansion applications of semiconducting polymer dots (Pdots) among optical nanomaterial field have long posed a challenge for researchers, promoting their intelligent application in multifunctional nano-imaging systems and integrated nanomedicine carriers for diagnosis and treatment. Despite notable progress, several inadequacies still persist in the field of Pdots, including the development of simplified near-infrared (NIR) optical nanoprobes, elucidation of their inherent biological behavior, and integration of information processing and nanotechnology into biomedical applications. This review aims to comprehensively elucidate the current status of Pdots as a classical nanophotonic material by discussing its advantages and limitations in terms of biocompatibility, adaptability to microenvironments in vivo, etc. Multifunctional integration and surface chemistry play crucial roles in realizing the intelligent application of Pdots. Information visualization based on their optical and physicochemical properties is pivotal for achieving detection, sensing, and labeling probes. Therefore, we have refined the underlying mechanisms and constructed multiple comprehensive original mechanism summaries to establish a benchmark. Additionally, we have explored the cross-linking interactions between Pdots and nanomedicine, potential yet complete biological metabolic pathways, future research directions, and innovative solutions for integrating diagnosis and treatment strategies. This review presents the possible expectations and valuable insights for advancing Pdots, specifically from chemical, medical, and photophysical practitioners' standpoints.

Unlocking the Potential of Extracellular Vesicles as the Next Generation Therapy: Challenges and Opportunities

BACKGROUND

Mesenchymal stem cells (MSCs) have undergone extensive investigation for their potential therapeutic applications, primarily attributed to their paracrine activity. Recently, researchers have been exploring the therapeutic potential of extracellular vesicles (EVs) released by MSCs.

METHODS

MEDLINE/PubMed and Google scholar databases were used for the selection of literature. The keywords used were mesenchymal stem cells, extracellular vesicles, clinical application of EVs and challenges EVs production.

RESULTS

These EVs have demonstrated robust capabilities in transporting intracellular cargo, playing a critical role in facilitating cell-to-cell communication by carrying functional molecules, including proteins, RNA species, DNAs, and lipids. Utilizing EVs as an alternative to stem cells offers several benefits, such as improved safety, reduced immunogenicity, and the ability to traverse biological barriers. Consequently, EVs have emerged as an increasingly attractive option for clinical use.

CONCLUSION

From this perspective, this review delves into the advantages and challenges associated with employing MSC-EVs in clinical settings, with a specific focus on their potential in treating conditions like lung diseases, cancer, and autoimmune disorders.

Optical Nanosensor Passivation Enables Highly Sensitive Detection of the Inflammatory Cytokine Interleukin-6

Interleukin-6 (IL-6) is known to play a critical role in the progression of inflammatory diseases such as cardiovascular disease, cancer, sepsis, viral infection, neurological disease, and autoimmune diseases. Emerging diagnostic and prognostic tools, such as optical nanosensors, experience challenges in translation to the clinic in part due to protein corona formation, dampening their selectivity and sensitivity. To address this problem, we explored the rational screening of several classes of biomolecules to be employed as agents in noncovalent surface passivation as a strategy to screen interference from nonspecific proteins. Findings from this screening were applied to the detection of IL-6 by a fluorescent-antibody-conjugated single-walled carbon nanotube (SWCNT)-based nanosensor. The IL-6 nanosensor exhibited highly sensitive and specific detection after passivation with a polymer, poly-l-lysine, as demonstrated by IL-6 detection in human serum within a clinically relevant range of 25 to 25,000 pg/mL, exhibiting a limit of detection over 3 orders of magnitude lower than prior antibody-conjugated SWCNT sensors. This work holds potential for the rapid and highly sensitive detection of IL-6 in clinical settings with future application to other cytokines or disease-specific biomarkers.

Supramolecular interaction in the action of drug delivery systems

Complex diseases and diverse clinical needs necessitate drug delivery systems (DDSs), yet the current performance of DDSs is far from ideal. Supramolecular interactions play a pivotal role in various aspects of drug delivery, encompassing biocompatibility, drug loading, stability, crossing biological barriers, targeting, and controlled release. Nevertheless, despite having some understanding of the role of supramolecular interactions in drug delivery, their incorporation is frequently overlooked in the design and development of DDSs. This perspective provides a brief analysis of the involved supramolecular interactions in the action of drug delivery, with a primary emphasis on the DDSs employed in the clinic, mainly liposomes and polymers, and recognized phenomena in research, such as the protein corona. The supramolecular interactions implicated in various aspects of drug delivery systems, including biocompatibility, drug loading, stability, spatiotemporal distribution, and controlled release, were individually analyzed and discussed. This perspective aims to trigger a comprehensive and systematic consideration of supramolecular interactions in the further development of DDSs. Supramolecular interactions embody the true essence of the interplay between the majority of DDSs and biological systems.

Stable "snow lantern-like" aggregates of silicon nanoparticles suitable as a drug delivery platform

Nanomedicine is a growing field where development of novel organic and inorganic materials is essential to meet the complex requirements for drug delivery. This includes biocompatibility, suitability for surface modifications, biodegradability, and stability sufficient to carry a drug payload through various tissues for the desired timespan. Porous silicon nanoparticles (pSi NP) are shown to have several beneficial traits in drug delivery in addition to a porous structure to maximize drug loading. The conventional synthesis of pSi NP using electrochemical etching is costly, time-consuming and requires large quantities of highly toxic hydrofluoric acid (HF). As such this research attempted a novel method to address these limitations. Mesoporous silicon nanoparticles were prepared by centrifugal Chemical Vapor Deposition (cCVD) without the use of HF. This process generated aggregates consisting of multiple primary particles fused into each other, similar to snowballs fused together in a snow-lantern (snowball pyramid). Our results demonstrated that the cCVD Si particles were versatile in terms of surface chemistry, colloidal stability, degradability, minimization of acute in vitro toxicity, and modulation of drug release. Dynamic light scattering, scanning electron microscopy, and cryogenic nitrogen adsorption isotherm measurements confirmed the overall size (210 nm), morphology, and pore size (14-16 nm) of the prepared materials. Agglomeration in phosphate-buffered saline (PBS) was minimized by PEGylation by a two-step grafting procedure that employed a primary amine linker. Finally, the release rate of a model drug, hydrocortisone, was evaluated with both PEGylated and pristine particles. Conclusively, these snow-lantern cCVD Si particles do indeed appear suitable for drug delivery.

Controlling nanoparticle-induced endothelial leakiness with the protein corona

Understanding nanoparticle-cell interaction is essential for advancing research in nanomedicine and nanotoxicology. Apart from the transcytotic pathway mediated by cellular recognition and energetics, nanoparticles (including nanomedicines) may harness the paracellular route for their transport by inducing endothelial leakiness at cadherin junctions. This phenomenon, termed as NanoEL, is correlated with the physicochemical properties of the nanoparticles in close association with cellular signalling, membrane mechanics, as well as cytoskeletal remodelling. However, nanoparticles in biological systems are transformed by the ubiquitous protein corona and yet the potential effect of the protein corona on NanoEL remains unclear. Using confocal fluorescence microscopy, biolayer interferometry, transwell, toxicity, and molecular inhibition assays, complemented by molecular docking, here we reveal the minimal to significant effects of the anionic human serum albumin and fibrinogen, the charge neutral immunoglobulin G as well as the cationic lysozyme on negating gold nanoparticle-induced endothelial leakiness in vitro and in vivo. This study suggests that nanoparticle-cadherin interaction and hence the extent of NanoEL may be partially controlled by pre-exposing the nanoparticles to plasma proteins of specific charge and topology to facilitate their biomedical applications.

A Review for Uncovering the "Protein-Nanoparticle Alliance": Implications of the Protein Corona for Biomedical Applications

Understanding both the physicochemical and biological interactions of nanoparticles is mandatory for the biomedical application of nanomaterials. By binding proteins, nanoparticles acquire new surface identities in biological fluids, the protein corona. Various studies have revealed the dynamic structure and nano-bio interactions of the protein corona. The binding of proteins not only imparts new surface identities to nanoparticles in biological fluids but also significantly influences their bioactivity, stability, and targeting specificity. Interestingly, recent endeavors have been undertaken to harness the potential of the protein corona instead of evading its presence. Exploitation of this 'protein-nanoparticle alliance' has significant potential to change the field of nanomedicine. Here, we present a thorough examination of the latest research on protein corona, encompassing its formation, dynamics, recent developments, and diverse bioapplications. Furthermore, we also aim to explore the interactions at the nano-bio interface, paving the way for innovative strategies to advance the application potential of the protein corona. By addressing challenges and promises in controlling protein corona formation, this review provides insights into the evolving landscape of the 'protein-nanoparticle alliance' and highlights emerging.

Exploring Present and Future Directions in Nano-Enhanced Optoelectronic Neuromodulation

Electrical neuromodulation has achieved significant translational advancements, including the development of deep brain stimulators for managing neural disorders and vagus nerve stimulators for seizure treatment. Optoelectronics, in contrast to wired electrical systems, offers the leadless feature that guides multisite and high spatiotemporal neural system targeting, ensuring high specificity and precision in translational therapies known as "photoelectroceuticals". This Account provides a concise overview of developments in novel optoelectronic nanomaterials that are engineered through innovative molecular, chemical, and nanostructure designs to facilitate neural interfacing with high efficiency and minimally invasive implantation.This Account outlines the progress made both within our laboratory and across the broader scientific community, with particular attention to implications in materials innovation strategies, studying bioelectrical activation with spatiotemporal methods, and applications in regenerative medicine. In materials innovation, we highlight a nongenetic, biocompatible, and minimally invasive approach for neuromodulation that spans various length scales, from single neurons to nerve tissues using nanosized particles and monolithic membranes. Furthermore, our discussion exposes the critical unresolved questions in the field, including mechanisms of interaction at the nanobio interface, the precision of cellular or tissue targeting, and integration into existing neural networks with high spatiotemporal modulation. In addition, we present the challenges and pressing needs for long-term stability and biocompatibility, scalability for clinical applications, and the development of noninvasive monitoring and control systems.In addressing the existing challenges in the field of nanobio interfaces, particularly for neural applications, we envisage promising strategic directions that could significantly advance this burgeoning domain. This involves a deeper theoretical understanding of nanobiointerfaces, where simulations and experimental validations on how nanomaterials interact spatiotemporally with biological systems are crucial. The development of more durable materials is vital for prolonged applications in dynamic neural interfaces, and the ability to manipulate neural activity with high specificity and spatial resolution, paves the way for targeting individual neurons or specific neural circuits. Additionally, integrating these interfaces with advanced control systems, possibly leveraging artificial intelligence and machine learning algorithms and programming dynamically responsive materials designs, could significantly ease the implementation of stimulation and recording. These innovations hold the potential to introduce novel treatment modalities for a wide range of neurological and systemic disorders.

Cell-excreted proteins mediate the interactions of differently sized silica nanoparticles during cellular uptake

Exposure to different types of nanoparticles (NPs) results in their deposition in human bodies. While most studies have examined the cellular uptake of only one type of NP at a time, how the dynamics of NP uptake may change in the presence of other types of NPs remains unclear. We therefore investigated the interplay of two differently sized SiO2 NPs during their uptake by A549 human lung carcinoma cells. Both NPs contained a CdSeTe core, which was labeled with different Cd isotopes to differentiate between them. Our study showed that the uptake of one size of SiO2 NPs either increased or decreased with the concentration of the other size of SiO2 NPs. This variation in uptake was attributable to the concentration-dependent aggregation of SiO2 NPs, as determined by the amount of cell-excreted proteins adsorbed on the NP surface. Further, the effects of the protein corona on the attachment of SiO2 NPs to the cell surface and uptake competition between differently sized SiO2 NPs also played important roles. Cell-excreted proteins were then analyzed by proteomics. Overall, the complex interactions between coexisting NPs of different physicochemical properties and cell-excreted proteins should be considered during bio-applications and bio-safety evaluations of NPs.

Ovalbumin interaction with polystyrene and polyethylene terephthalate microplastics alters its structural properties

Contaminating microplastics can interact with food proteins in the food matrix and during digestion. This study investigated adsorption of chicken egg protein ovalbumin to polystyrene (PS, 110 and 260 μm) and polyethylene terephthalate (PET, 140 μm) MPs in acidic and neutral conditions and alterations in ovalbumin structure. Ovalbumin adsorption affinity depended on MPs size (smaller > larger), type (PS > PET) and pH (pH 3 > pH 7). In bulk solution, MPs does not change ovalbumin secondary structure significantly, but induces loosening (at pH 3) and tightening (at pH 7) of tertiary structure. Formed soft corona exclusively consists of full length non-native ovalbumin, while in hard corona also shorter ovalbumin fragments were found. At pH 7 soft corona ovalbumin has rearranged but still preserved level of ordered secondary structure, resulting in preserved thermostability and proteolytic stability, but decreased ability to form fibrils upon heating. Secondary structure changes in soft corona resemble changes in native ovalbumin induced by heat treatment (80 °C). Ovalbumin is abundantly present in corona around microplastics also in the presence of other egg white proteins. These results imply that microplastics contaminating food may bind and change structure and functional properties of the main egg white protein.

Sources of biases in the in vitro testing of nanomaterials: the role of the biomolecular corona

The biological fate of nanomaterials (NMs) is driven by specific interactions through which biomolecules, naturally adhering onto their surface, engage with cell membrane receptors and intracellular organelles. The molecular composition of this layer, called the biomolecular corona (BMC), depends on both the physical-chemical features of the NMs and the biological media in which the NMs are dispersed and cells grow. In this work, we demonstrate that the widespread use of 10% fetal bovine serum in an in vitro assay cannot recapitulate the complexity of in vivo systemic administration, with NMs being transported by the blood. For this purpose, we undertook a comparative journey involving proteomics, lipidomics, high throughput multiparametric in vitro screening, and single molecular feature analysis to investigate the molecular details behind this in vivo/in vitro bias. Our work indirectly highlights the need to introduce novel, more physiological-like media closer in composition to human plasma to produce realistic in vitro screening data for NMs. We also aim to set the basis to reduce this in vitro-in vivo mismatch, which currently limits the formulation of NMs for clinical settings.

Research Progress on Liposome Pulmonary Delivery of Mycobacterium tuberculosis Nucleic Acid Vaccine and Its Mechanism of Action

Traditional vaccines have played an important role in the prevention and treatment of infectious diseases, but they still have problems such as low immunogenicity, poor stability, and difficulty in inducing lasting immune responses. In recent years, the nucleic acid vaccine has emerged as a relatively cheap and safe new vaccine. Compared with traditional vaccines, nucleic acid vaccine has some unique advantages, such as easy production and storage, scalability, and consistency between batches. However, the direct administration of naked nucleic acid vaccine is not ideal, and safer and more effective vaccine delivery systems are needed. With the rapid development of nanocarrier technology, the combination of gene therapy and nanodelivery systems has broadened the therapeutic application of molecular biology and the medical application of biological nanomaterials. Nanoparticles can be used as potential drug-delivery vehicles for the treatment of hereditary and infectious diseases. In addition, due to the advantages of lung immunity, such as rapid onset of action, good efficacy, and reduced adverse reactions, pulmonary delivery of nucleic acid vaccine has become a hot spot in the field of research. In recent years, lipid nanocarriers have become safe, efficient, and ideal materials for vaccine delivery due to their unique physical and chemical properties, which can effectively reduce the toxic side effects of drugs and achieve the effect of slow release and controlled release, and there have been a large number of studies using lipid nanocarriers to efficiently deliver target components into the body. Based on the delivery of tuberculosis (TB) nucleic acid vaccine by lipid carrier, this article systematically reviews the advantages and mechanism of liposomes as a nucleic acid vaccine delivery carrier, so as to lay a solid foundation for the faster and more effective development of new anti-TB vaccine delivery systems in the future.

Protein Corona-Mediated Inhibition of Nanozyme Activity: Impact of Protein Shape

During biomedical applications, nanozymes, exhibiting enzyme-like characteristics, inevitably come into contact with biological fluids in living systems, leading to the formation of a protein corona on their surface. Although it is acknowledged that molecular adsorption can influence the catalytic activity of nanozymes, there is a dearth of understanding regarding the impact of the protein corona on nanozyme activity and its determinant factors. In order to address this gap, we employed the AuNR@Pt@PDDAC [PDDAC, poly(diallyldimethylammonium chloride)] nanorod (NR) as a model nanozyme with multiple activities, including peroxidase, oxidase, and catalase-mimetic activities, to investigate the inhibitory effects of the protein corona on the catalytic activity. After the identification of major components in the plasma protein corona on the NR, we observed that spherical proteins and fibrous proteins induced distinct inhibitory effects on the catalytic activity of nanozymes. To elucidate the underlying mechanism, we uncovered that the adsorbed proteins assembled on the surface of the nanozymes, forming protein networks (PNs). Notably, the PNs derived from fibrous proteins exhibited a screen mesh-like structure with smaller pore sizes compared to those formed by spherical proteins. This structural disparity resulted in a reduced efficiency for the permeation of substrate molecules, leading to a more robust inhibition in activity. These findings underscore the significance of the protein shape as a crucial factor influencing nanozyme activity. This revelation provides valuable insights for the rational design and application of nanozymes in the biomedical fields.

Advancing In Situ Analysis of Biomolecular Corona: Opportunities and Challenges in Utilizing Field-Flow Fractionation

The biomolecular corona, a complex layer of biological molecules, envelops nanoparticles (NPs) upon exposure to biological fluids including blood. This dynamic interface is pivotal for the advancement of nanomedicine, particularly in areas of therapy and diagnostics. In situ analysis of the biomolecular corona is crucial, as it can substantially improve our ability to accurately predict the biological fate of nanomedicine and, therefore, enable development of more effective, safe, and precisely targeted nanomedicines. Despite its importance, the repertoire of techniques available for in situ analysis of the biomolecular corona is surprisingly limited. This tutorial review provides an overview of the available techniques for in situ analysis of biomolecular corona with a particular focus on exploring both the advantages and the limitations inherent in the use of field-flow fractionation (FFF) for in situ analysis of the biomolecular corona. It delves into how FFF can unravel the complexities of the corona, enhancing our understanding and guiding the design of next-generation nanomedicines for medical use.

Current status of controlled onco-therapies based on metal organic frameworks

Despite consecutive efforts devoted to the establishment of innovative therapeutics for cancer control, cancer remains as a primary global public health concern. Achieving controlled release of anti-cancer agents may add great value to the field of oncology that requires the involvement of nanotechnologies. Metal organic frameworks (MOFs) hold great promise in this regard owing to their unique structural properties. MOFs can act as superior candidates for drug delivery given their porous structure and large loading area, and can be prepared into anti-cancer therapeutics by incorporating stimuli-sensitive components into the ligands or nodes of the framework. By combing through chemical and physical features of MOFs favorable for onco-therapeutic applications and current cancer treatment portfolios taking advantages of these characteristics, this review classified MOFs feasible for establishing controlled anti-cancer modalities into 6 categories, outlined the corresponding strategies currently available for each type of MOF, and identified understudied areas and future opportunities towards innovative MOF design for improved or expanded clinical anti-cancer applications.

Protein Corona Composition of Gold Nanocatalysts

The interaction between nanoparticles (NPs) and biological environments is profoundly influenced by a stable, strongly adsorbed "hard" protein corona. This corona significantly determines the NPs' pharmacokinetics and biological destiny. Our study delves into the mechanisms by which colloidal Au nanocrystals that are synthesized electrochemically without surface-capping organic ligands, known as CNM-Au8, traverse the blood-brain barrier (BBB) and target human brain tissue for treating neurodegenerative disorders. We discovered that upon interaction with human plasma, CNM-Au8 gold nanocrystals (AuNCs) effectively attract a variety of crucial apolipoproteins, notably apolipoproteins E, to their surfaces. This interaction likely facilitates their passage through the BBB. Furthermore, the coronas of these AuNCs exhibit a substantial presence of albumin and a notable absence of opsonin-based proteins, contributing to prolonged blood circulation. These characteristics align well with the clinical performance observed for the CNM-Au8 NCs. This study highlights that AuNCs with intentionally engineered structures and surfactant-free surfaces can create a distinct protein corona composition. This finding holds significant promise for the development of advanced therapeutic agents aimed at combating neurodegenerative diseases.

Seed-Induced Living Two-Dimensional (2D) Supramolecular Polymerization in Water: Implications on Protein Adsorption and Enzyme Inhibition

In biological systems, programmable supramolecular frameworks characterized by coordinated directional non-covalent interactions are widespread. However, only a small number of reports involve pure water-based dynamic supramolecular assembly of artificial π-amphiphiles, primarily due to the formidable challenge of counteracting the strong hydrophobic dominance of the π-surface in water, leading to undesired kinetic traps. This study reveals the pathway complexity in hydrogen-bonding-mediated supramolecular polymerization of an amide-functionalized naphthalene monoimide (NMI) building block with a hydrophilic oligo-oxyethylene (OE) wedge. O-NMI-2 initially produced entropically driven, collapsed spherical particles in water (Agg-1); however, over a span of 72 h, these metastable Agg-1 gradually transformed into two-dimensional (2D) nanosheets (Agg-2), favoured by both entropy and enthalpy contributions. The intricate self-assembly pathways in O-NMI-2 enable us to explore seed-induced living supramolecular polymerization (LSP) in water for controlled synthesis of monolayered 2D assemblies. Furthermore, we demonstrated the nonspecific surface adsorption of a model enzyme, serine protease α-Chymotrypsin (α-ChT), and consequently the enzyme activity, which could be regulated by controlling the morphological transformation of O-NMI-2 from Agg-1 to Agg-2. We delve into the thermodynamic aspects of such shape-dependent protein-surface interactions and unravel the impact of seed-induced LSP on temporally controlling the catalytic activity of α-ChT.

The In Vivo Biological Fate of Protein Corona: A Comparative PET Study of the Fate of Soft and Hard Protein Corona in Healthy Animal Models

Radiolabeling and nuclear imaging techniques are used to investigate the biodistribution patterns of the soft and hard protein corona around poly (lactic-co-glycolic acid) nanoparticles (PLGA NPs) after administration to healthy mice. Soft and hard protein coronas of 131I-labeled BSA or 131I-labeled serum are formed on PLGA NPs functionalized with either polyehtylenimine (PEI) or bovine serum albumin (BSA). The exchangeability of hard and soft corona is assessed in vitro by gamma counting exposing PLGA NPs with corona to non-labeled BSA, serum, or simulated body fluid. PEI PLGA NPs form larger and more stable coronas than BSA PLGA NPs. Soft coronas are more exchangeable than hard ones. The in vivo fate of PEI PLGA NPs coated with preformed 18F-labeled BSA hard and soft coronas is assessed by positron emission tomography (PET) following intravenous administration. While the soft corona shows a biodistribution similar to free 18F BSA with high activity in blood and kidney, the hard corona follows patterns characteristic of nanoparticles, accumulating in the lungs, liver, and spleen. These results show that in vivo fates of soft and hard corona are different, and that soft corona is more easily exchanged with proteins from the body, while hard corona is largely retained on the nanoparticle surface.

Long-Term Intracellular Tracking of Label-Free Nanoparticles in Live Cells and Tissues with Confocal Microscopy

The label-free imaging of inorganic nanoparticles (NPs) using confocal laser scanning microscopy (CLSM) provides a powerful and versatile tool for studying interactions between NPs and biological systems. Without the need for exogenous labels or markers, it simply benefits from the differential scattering of visible photons between biomaterials and inorganic NPs. Validation experiments conducted on fixed and living cells in real-time, as well as mouse tissue sections following parenteral administration of NPs. Additionally, by incorporating reporter fluorophores and utilizing both reflectance and fluorescence imaging modalities, the method enables high-resolution multiplex imaging of cellular structures and NPs. Different sizes and concentrations of Au NPs are tested as for Ag, Fe3O4, and CeO2 NPs, all with biological interest. Overall, the comprehensive study of NP imaging by confocal microscopy in reflectance mode provides valuable insights and tools for researchers interested in monitoring the nano-bio interactions.

Selective inhibition of partial EMT-induced tumour cell growth by cerium valence states of extracellular ceria nanoparticles for anticancer treatment

Targeting specific tumour cells and their microenvironments is essential for enhancing the efficacy of chemotherapy and reducing its side effects. A partial epithelial-to-mesenchymal transition state (pEMT, with a hybrid epithelial/mesenchymal phenotype) in tumour cells is an attractive targeting for anticancer treatment because it potentially provides maximal stemness and metastasis relevant to malignant cancer stem cell-like features. However, treatment strategies to target pEMT in tumour cells remain a challenge. This study demonstrates that extracellular cerium oxide nanoparticles (CNPs) selectively inhibit the growth of pEMT-induced tumour cells, without affecting full epithelial tumour cells. Herein, highly concentrated Ce3+ and Ce4+ ions are formed on CNP-layered poly-L-lactic acid surfaces. Cell cultures of pEMT-induced and uninduced lung cancer cell lines on the CNP-layered substrates allow the effect of extracellular CNPs on tumour cell growth to be investigated. The extracellular CNPs with dominant Ce3+ and Ce4+ ions were able to trap pEMT-induced tumour cells in a growth-arrested quiescent/dormant or cytostatic state without generating redox-related reactive oxygen species (ROS), i.e. non-redox mechanisms. The dominant Ce3+ state provided highly efficient growth inhibition of the pEMT-induced tumour cells. In contrast, the dominant Ce4+ state showed highly selective and appropriate growth regulation of normal and tumour cells, including a mesenchymal phenotype. Furthermore, Ce4+-CNPs readily adsorbed serum-derived fibronectin and laminin. Cerium valence-specific proteins adsorbed on CNPs may influence receptor-mediated cell-CNP interactions, leading to tumour cell growth inhibition. These findings provide new perspectives for pEMT-targeting anticancer treatments based on the unique biointerface of extracellular CNPs with different Ce valence states.

Development of a fast and simple method for the isolation of superparamagnetic iron oxide nanoparticles protein corona from protein-rich matrices

The adsorption of proteins onto the surface of nanoparticle (NP) leads to the formation of the so-called "protein corona" as consisting both loosely and tightly bound proteins. It is well established that the biological identity of NPs that may be acquired after exposure to a biological matrix is mostly provided by the components of the hard corona as the pristine surface is generally less accessible for binding. For that reason, the isolation and the characterisation of the NP-corona complexes and identification of the associated biomolecules can help in understanding its biological behaviour. Established methods for the isolation of the NP-HC complexes are time-demanding and can lead to different results based on the isolation method applied. Herein, we have developed a fast and simple method using ferromagnetic beads isolated from commercial MACS column and used for the isolation of superparamagnetic NP following exposure to different types of biological milieu. We first demonstrated the ability to easily isolate superparamagnetic iron oxide NPs (IONPs) from different concentrations of human blood plasma, and also tested the method on the corona isolation using more complex biological matrices, such as culture medium containing pulmonary mucus where the ordinary corona methods cannot be applied. Our developed method showed less than 20% difference in plasma corona composition when compared with centrifugation. It also showed effective isolation of NP-HC complexes from mucus-containing culture media upon comparing with centrifugation and MACS columns, which failed to wash out the unbound proteins. Our study was supported with a full characterisation profile including dynamic light scattering, nanoparticle tracking analysis, analytical disk centrifuge, and zeta potentials. The biomolecules/ proteins composing the HC were separated by vertical gel electrophoresis and subsequently analysed by liquid chromatography-tandem mass spectrometry. In addition to our achievements in comparing different isolation methods to separate IONPs with corona from human plasma, this is the first study that provides a complete characterisation profile of particle protein corona after exposure in vitro to pulmonary mucus-containing culture media.

Biomolecular Corona of Gold Nanoparticles: The Urgent Need for Strong Roots to Grow Strong Branches

Gold nanoparticles (GNPs) are largely employed in diagnostics/biosensors and are among the most investigated nanomaterials in biology/medicine. However, few GNP-based nanoformulations have received FDA approval to date, and promising in vitro studies have failed to translate to in vivo efficacy. One key factor is that biological fluids contain high concentrations of proteins, lipids, sugars, and metabolites, which can adsorb/interact with the GNP's surface, forming a layer called biomolecular corona (BMC). The BMC can mask prepared functionalities and target moieties, creating new surface chemistry and determining GNPs' biological fate. Here, the current knowledge is summarized on GNP-BMCs, analyzing the factors driving these interactions and the biological consequences. A partial fingerprint of GNP-BMC analyzing common patterns of composition in the literature is extrapolated. However, a red flag is also risen concerning the current lack of data availability and regulated form of knowledge on BMC. Nanomedicine is still in its infancy, and relying on recently developed analytical and informatic tools offers an unprecedented opportunity to make a leap forward. However, a restart through robust shared protocols and data sharing is necessary to obtain "stronger roots". This will create a path to exploiting BMC for human benefit, promoting the clinical translation of biomedical nanotools.

Protein Aggregation on Metal Oxides Governs Catalytic Activity and Cellular Uptake

Engineering of catalytically active inorganic nanomaterials holds promising prospects for biomedicine. Catalytically active metal oxides show applications in enhancing wound healing but have also been employed to induce cell death in photodynamic or radiation therapy. Upon introduction into a biological system, nanomaterials are exposed to complex fluids, causing interaction and adsorption of ions and proteins. While protein corona formation on nanomaterials is acknowledged, its modulation of nanomaterial catalytic efficacy is less understood. In this study, proteomic analyses and nano-analytic methodologies quantify and characterize adsorbed proteins, correlating this protein layer with metal oxide catalytic activity in vitro and in vivo. The protein corona comprises up to 280 different proteins, constituting up to 38% by weight. Enhanced complement factors and other opsonins on nanocatalyst surfaces lead to their uptake into macrophages when applied topically, localizing >99% of the nanomaterials in tissue-resident macrophages. Initially, the formation of the protein corona significantly reduces the nanocatalysts' activity, but this activity can be partially recovered in endosomal conditions due to the proteolytic degradation of the corona. Overall, the research reveals the complex relationship between physisorbed proteins and the catalytic characteristics of specific metal oxide nanoparticles, providing design parameters for optimizing nanocatalysts in complex biological environments.

Probing Protein Corona Formation around Gold Nanoparticles: Effects of Surface Coating

There has been much interest in integrating various inorganic nanoparticles (nanoscale colloids) in biology and medicine. However, buildup of a protein corona around the nanoparticles in biological media, driven by nonspecific interactions, remains a major hurdle for the translation of nanomedicine into clinical applications. In this study, we investigate the interactions between gold nanoparticles and serum proteins using a series of dihydrolipoic acid (DHLA)-based ligands. We employed gel electrophoresis combined with UV-vis absorption and dynamic light scattering to correlate protein adsorption with the nature and size of the ligand used. For instance, we found that AuNPs capped with DHLA alone promote nonspecific protein adsorption. In comparison, capping AuNPs with polyethylene glycol- or zwitterion-appended DHLA essentially prevents corona formation, regardless of ligand charge and size. Our results highlight the crucial role of surface chemistry and core material in protein corona formation and offer valuable information for the design of colloidal nanomaterials for biological applications.

Tapered chiral nanoparticles as broad-spectrum thermally stable antivirals for SARS-CoV-2 variants

The incessant mutations of viruses, variable immune responses, and likely emergence of new viral threats necessitate multiple approaches to novel antiviral therapeutics. Furthermore, the new antiviral agents should have broad-spectrum activity and be environmentally stable. Here, we show that biocompatible tapered CuS nanoparticles (NPs) efficiently agglutinate coronaviruses with binding affinity dependent on the chirality of surface ligands and particle shape. L-penicillamine-stabilized NPs with left-handed curved apexes display half-maximal inhibitory concentrations (IC50) as low as 0.66 pM (1.4 ng/mL) and 0.57 pM (1.2 ng/mL) for pseudo-type SARS-CoV-2 viruses and wild-type Wuhan-1 SARS-CoV-2 viruses, respectively, which are about 1,100 times lower than those for antibodies (0.73 nM). Benefiting from strong NPs-protein interactions, the same particles are also effective against other strains of coronaviruses, such as HCoV-HKU1, HCoV-OC43, HCoV-NL63, and SARS-CoV-2 Omicron variants with IC50 values below 10 pM (21.8 ng/mL). Considering rapid response to outbreaks, exposure to elevated temperatures causes no change in the antiviral activity of NPs while antibodies are completely deactivated. Testing in mice indicates that the chirality-optimized NPs can serve as thermally stable analogs of antiviral biologics complementing the current spectrum of treatments.

DNA corona on nanoparticles leads to an enhanced immunostimulatory effect with implications for autoimmune diseases

Autoimmune and inflammatory diseases are highly complex, limiting treatment and the development of new therapies. Recent work has shown that cell-free DNA bound to biological microparticles is linked to systemic lupus erythematosus, a prototypic autoimmune disease. However, the heterogeneity and technical challenges associated with the study of biological particles have hindered a mechanistic understanding of their role. Our goal was to develop a well-controlled DNA-particle model system to understand how DNA-particle complexes affect cells. We first characterized the adsorption of DNA on the surface of polystyrene nanoparticles (200 nm and 2 µm) using transmission electron microscopy, dynamic light scattering, and colorimetric DNA concentration assays. We found that DNA adsorbed on the surface of nanoparticles was resistant to degradation by DNase 1. Macrophage cells incubated with the DNA-nanoparticle complexes had increased production of pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6). We probed two intracellular DNA sensing pathways, toll-like receptor 9 (TLR9) and cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING), to determine how cells sense the DNA-nanoparticle complexes. We found that the cGAS-STING pathway is the primary route for the interaction between DNA-nanoparticles and macrophages. These studies provide a molecular and cellular-level understanding of DNA-nanoparticle-macrophage interactions. In addition, this work provides the mechanistic information necessary for future in vivo experiments to elucidate the role of DNA-particle interactions in autoimmune diseases, providing a unique experimental framework to develop novel therapeutic approaches.

Impact of Whey Protein Corona Formation around TiO2 Nanoparticles on Their Physiochemical Properties and Gastrointestinal Fate

Previously, we found that whey proteins form biomolecular coronas around titanium dioxide (TiO2) nanoparticles. Here, the gastrointestinal fate of whey protein-coated TiO2 nanoparticles and their interactions with gut microbiota were investigated. The antioxidant activity of protein-coated nanoparticles was enhanced after simulated digestion. The structure of the whey proteins was changed after they adsorbed to the surfaces of the TiO2 nanoparticles, which reduced their hydrolysis under simulated gastrointestinal conditions. The presence of protein coronas also regulated the impact of the TiO2 nanoparticles on colonic fermentation, including promoting the production of short-chain fatty acids. Bare TiO2 nanoparticles significantly increased the proportion of harmful bacteria and decreased the proportion of beneficial bacteria, but the presence of protein coronas alleviated this effect. In particular, the proportion of beneficial bacteria, such as Bacteroides and Bifidobacterium, was enhanced for the coated nanoparticles. Our results suggest that the formation of a whey protein corona around TiO2 nanoparticles may have beneficial effects on their behavior within the colon. This study provides valuable new insights into the potential impact of protein coronas on the gastrointestinal fate of inorganic nanoparticles.

Influence of polystyrene nanoparticles on the toxicity of tetrabromobisphenol A in human intestinal cell lines

Research and regulatory efforts in toxicology are increasingly focused on the development of suitable non-animal methodologies for human health risk assessment. In this work we used human intestinal Caco-2 and HT29/MTX cell lines to address the potential risks of mixtures of the emerging contaminants tetrabromobisphenol A (TBBPA) and commercial polystyrene nanoparticles (PSNPs). We employed different in vitro settings to evaluate basal cytotoxicity through three complementary endpoints (metabolic activity, plasmatic, and lysosomal membrane integrity) and the induction of the oxidative stress and DNA damage responses with specific endpoints. Although no clear pattern was observed, our findings highlight the predominant impact of TBBPA in the combined exposures under subcytotoxic conditions and a differential behavior of the Caco-2 and HT29/MTX co-culture system. Distinctive outcomes detected with the mixture treatments include reactive oxygen species (ROS) increases, disturbances of mitochondrial inner membrane potential, generation of alkali-sensitive sites in DNA, as well as significant changes in the expression levels of relevant DNA and oxidative stress related genes.

A Paramagnetic Metal-Organic Framework Enhances Mild Magnetic Hyperthermia Therapy by Downregulating Heat Shock Proteins and Promoting Ferroptosis via Aggravation of Two-Way Regulated Redox Dyshomeostasis

Mild magnetic hyperthermia therapy (MMHT) holds great potential in treating deep-seated tumors, but its efficacy is impaired by the upregulation of heat shock proteins (HSPs) during the treatment process. Herein, Lac-FcMOF, a lactose derivative (Lac-NH2 ) modified paramagnetic metal-organic framework (FcMOF) with magnetic hyperthermia property and thermal stability, has been developed to enhance MMHT therapeutic efficacy. In vitro studies showed that Lac-FcMOF aggravates two-way regulated redox dyshomeostasis (RDH) via magnetothermal-accelerated ferricenium ions-mediated consumption of glutathione and ferrocene-catalyzed generation of ∙OH to induce oxidative damage and inhibit heat shock protein 70 (HSP70) synthesis, thus significantly enhancing the anti-cancer efficacy of MMHT. Aggravated RDH promotes glutathione peroxidase 4 inactivation and lipid peroxidation to promote ferroptosis, which further synergizes with MMHT. H22-tumor-bearing mice treated with Lac-FcMOF under alternating magnetic field (AMF) demonstrated a 90.4% inhibition of tumor growth. This work therefore provides a new strategy for the simple construction of a magnetic hyperthermia agent that enables efficient MMHT by downregulating HSPs and promoting ferroptosis through the aggravation of two-way regulated RDH.

Modulating the toxicity of engineered nanoparticles by controlling protein corona formation: Recent advances and future prospects

With the rapid development and widespread application of engineered nanoparticles (ENPs), understanding the fundamental interactions between ENPs and biological systems is essential to assess and predict the fate of ENPs in vivo. When ENPs are exposed to complex physiological environments, biomolecules quickly and inevitably adsorb to ENPs to form a biomolecule corona, such as a protein corona (PC). The formed PC has a significant effect on the physicochemical properties of ENPs and gives them a brand new identity in the biological environment, which determines the subsequent ENP-cell/tissue/organ interactions. Controlling the formation of PCs is therefore of utmost importance to accurately predict and optimize the behavior of ENPs within living organisms, as well as ensure the safety of their applications. In this review, we provide an overview of the fundamental aspects of the PC, including the formation mechanism, composition, and frequently used characterization techniques. We comprehensively discuss the potential impact of the PC on ENP toxicity, including cytotoxicity, immune response, and so on. Additionally, we summarize recent advancements in manipulating PC formation on ENPs to achieve the desired biological outcomes. We further discuss the challenges and prospects, aiming to provide valuable insights for a better understanding and prediction of ENP behaviors in vivo, as well as the development of low-toxicity ENPs.

Carfilzomib-Loaded Ternary Polypeptide Nanoparticles Stabilized by Polycationic Complexation

Carfilzomib (CFZ) is a second-generation proteasome inhibitor showing great efficacy in multiple myeloma treatment, yet its clinical applications for other diseases such as solid cancers are limited due to low aqueous solubility and poor biostability. Ternary polypeptide nanoparticles (tPNPs) are drug carriers that we previously reported to overcome these pharmaceutical limitations by entrapping CFZ in the core of the nanoparticles and protecting the drugs from degradation in biological media. However, preclinical studies revealed that tPNPs would require further improvement in particle stability to suppress initial burst drug release and thus achieve prolonged inhibition of proteasome activity with CFZ against tumor cells in vivo. In this study, CFZ-loaded tPNPs are stabilized by polycations which have varying pKa values and thus differently modulate nanoparticle stability in response to solution pH. Through polyion complexation, the polycations appeared to stabilize the core of tPNPs entrapping CFZ-cyclodextrin inclusion complexes while allowing for uniform particle size before and after freeze drying. Interestingly, CFZ-loaded tPNPs (CFZ/tPNPs) showed pH-dependent drug release kinetics, which accelerated CFZ release as solution acidity increased (pH < 6) without compromising particle stability at the physiological condition (pH 7.4). In vitro cytotoxicity and proteasome activity assays confirmed that tPNPs stabilized with cationic polymers improved bioactivity of CFZ against CFZ-resistant cancer cells, which would be greatly beneficial in combination with pH-dependent drug release for treatment of solid cancers with drug resistance and tumor microenvironment acidosis by using CFZ and other proteasome inhibitors.

Nano-Bio Interactions: Exploring the Biological Behavior and the Fate of Lipid-Based Gene Delivery Systems

Gene therapy for many diseases is rapidly becoming a reality, as demonstrated by the recent approval of various nucleic acid-based therapeutics. Non-viral systems such as lipid-based carriers, lipid nanoparticles (LNPs), for delivering different payloads including small interfering RNA, plasmid DNA, and messenger RNA have been particularly extensively explored and developed for clinical uses. One of the most important issues in LNP development is delivery to extrahepatic tissues. To achieve this, various lipids and lipid-like materials are being examined and screened. Several LNP formulations that target extrahepatic tissues, such as the spleen and the lungs have been developed by adjusting the lipid compositions of LNPs. However, mechanistic details of how the characteristics of LNPs affect delivery efficiency remains unclear. The purpose of this review is to provide an overview of LNP-based nucleic acid delivery focusing on LNP components and their structures, as well as discussing biological factors, such as biomolecular corona and cellular responses related to the delivery efficiency.

Surface (bio)-functionalization of metallic materials: How to cope with real interfaces?

Metallic materials are an important class of biomaterials used in various medical devices, owing to a suitable combination of their mechanical properties. The (bio)-functionalization of their surfaces is frequently performed for biocompatibility requirements, as it offers a powerful way to control their interaction with biological systems. This is particularly important when physicochemical processes and biological events, mainly involving proteins and cells, are initiated at the host-material interface. This review addresses the state of "real interfaces" in the context of (bio)-functionalization of metallic materials, and the necessity to cope with it to avoid frequent improper evaluation of the procedure used. This issue is, indeed, well-recognized but often neglected and emerges from three main issues: (i) ubiquity of surface contamination with organic compounds, (ii) reactivity of metallic surfaces in biological medium, and (iii) discrepancy in (bio)-functionalization procedures between expectations and reality. These disturb the assessment of the strategies adopted for surface modifications and limit the possibilities to provide guidelines for their improvements. For this purpose, X-ray photoelectrons spectroscopy (XPS) comes to the rescue. Based on significant progresses made in methodological developments, and through a large amount of data compiled to generate statistically meaningful information, and to insure selectivity, precision and accuracy, the state of "real interfaces" is explored in depth, while looking after the two main constituents: (i) the bio-organic adlayer, in which the discrimination between the compounds of interest (anchoring molecules, coupling agents, proteins, etc) and organic contaminants can be made, and (ii) the metallic surface, which undergoes dynamic processes due to their reactivity. Moreover, through one of the widespread (bio)-functionalization strategy, given as a case study, a particular attention is devoted to describe the state of the interface at different stages (composition, depth distribution of contaminants and (bio)compounds of interest) and the mode of protein retention. It is highlighted, in particular, that the occurrence or improvement of bioactivity does not demonstrate that the chemical schemes worked in reality. These aspects are particularly essential to make progress on the way to choose the suitable (bio)-functionalization strategy and to provide guidelines to improve its efficiency.

Unravelling the role of lipid composition on liposome-protein interactions

Upon in vivo administration of nanoparticles, a protein corona forms on their surface and affects their half-life in circulation, biodistribution properties, and stability; in turn, the composition of the protein corona depends on the physico-chemical properties of the nanoparticles. We have previously observed lipid composition-dependent in vitro and in vivo microRNA delivery from lipid nanoparticles. Here, we carried out an extensive physico-chemical characterisation to understand the role of the lipid composition on the in vivo fate of lipid-based nanoparticles. We used a combination of differential scanning calorimetry (DSC), membrane deformability measurements, isothermal titration calorimetry (ITC), and dynamic light scattering (DLS) to probe the interactions between the nanoparticle surface and bovine serum albumin (BSA) as a model protein. The lipid composition influenced membrane deformability, improved lipid intermixing, and affected the formation of lipid domains while BSA binding to the liposome surface was affected by the PEGylated lipid content and the presence of cholesterol. These findings highlight the importance of the lipid composition on the protein-liposome interaction and provide important insights for the design of lipid-based nanoparticles for drug delivery applications.

Unveiling the Biologically Dynamic Degradation of Iron Oxide Nanoparticles via a Continuous Flow System

Nanomaterials are increasingly being employed for biomedical applications, necessitating a comprehensive understanding of their degradation behavior and potential toxicity in the biological environment. This study utilizes a continuous flow system to simulate the biologically relevant degradation conditions and investigate the effects of pH, protein, redox species, and chelation ligand on the degradation of iron oxide nanoparticles. The morphology, aggregation state, and relaxivity of iron oxide nanoparticles after degradation are systematically characterized. The results reveal that the iron oxide nanoparticles degrade at a significantly higher rate under the acidic environment. Moreover, incubation with bovine serum albumin enhances the stability and decreases the dissolution rate of iron oxide nanoparticles. In contrast, glutathione accelerates the degradation of iron oxide nanoparticles, while the presence of sodium citrate leads to the fastest degradation. This study reveals that iron oxide nanoparticles undergo degradation through various mechanisms in different biological microenvironments. Furthermore, the dissolution and aggregation of iron oxide nanoparticles during degradation significantly impact their relaxivity, which has implications for their efficacy as magnetic resonance imaging contrast agents in vivo. The results provide valuable insights for assessing biosafety and bridge the gap between fundamental research and clinical applications of iron oxide nanoparticles.

Generation of a Hydrophobic Protrusion on Nanoparticles to Improve the Membrane-Anchoring Ability and Cellular Internalization

Controlling the nanoparticle-cell membrane interaction to achieve easy and fast membrane anchoring and cellular internalization is of great importance in a variety of biomedical applications. Here we report a simple and versatile strategy to maneuver the nanoparticle-cell membrane interaction by creating a tunable hydrophobic protrusion on Janus particles through swelling-induced symmetry breaking. When the Janus particle contacts cell membrane, the protrusion will induce membrane wrapping, leading the particles to docking to the membrane, followed by drawing the whole particles into the cell. The efficiencies of both membrane anchoring and cellular internalization can be promoted by optimizing the size of the protrusion. In vitro, the Janus particles can quickly anchor to the cell membrane in 1 h and be internalized within 24 h, regardless of the types of cells involved. In vivo, the Janus particles can effectively anchor to the brain and skin tissues to provide a high retention in these tissues after intracerebroventricular, intrahippocampal, or subcutaneous injection. This strategy involving the creation of a hydrophobic protrusion on Janus particles to tune the cell-membrane interaction holds great potential in nanoparticle-based biomedical applications.