Nanoparticle protein corona: from structure and function to therapeutic targeting

Application of Strontium Chloride Hexahydrate to Synthesize Strontium-Substituted Carbonate Apatite as a pH-Sensitive, Biologically Safe, and Highly Efficient siRNA Nanocarrier

Naked siRNAs are sensitive to enzymatic degradation, phagocytic entrapment, quick renal excretion, membrane impermeability, endosomal escape, and off-target effects. Designing a safe and efficient nanocarrier for siRNA delivery to the target site without toxicity remains a significant hurdle in gene therapy. CA is a unique derivative of hydroxyapatite and a highly pH-sensitive nanocarrier with strong particle aggregation and a high polydispersity index. Strontium (Sr2+), a group two divalent metal in the periodic table, has been reported for substituting calcium (Ca2+) ions from the apatite lattice and limiting particle growth/aggregation. This study used strontium chloride hexahydrate (SrCl2·6H2O) salt to develop a Sr-substituted CA (Sr-CA) nanocarrier with ∼30 nm size, spherical shape, less aggregation, homodispersity, and a fair anionic charge. Sr-CA demonstrated a large surface area-to-volume ratio, an improved cargo loading efficiency, and enhanced cellular uptake in HEK-293 cells. Moreover, Sr-CA is a pH-responsive nanocarrier responsible for its long physiological stability, efficient endosomal escape, and optimal cargo delivery within cells. These NPs have differential effects on MAPK1, MAP2K4, PIK3Ca, CAMK4, and p53 gene expression in HEK-293 cells without showing any significant cytotoxicity in cell growth properties. Gene silencing by Sr-CA-mediated siRNA delivery against MAPK1, MAP2K4, PIK3Ca, and CAMK4 genes significantly decreased the level of target gene expression and cell survival, demonstrating successful intracellular siRNA delivery in HEK-293 cells. Additionally, biocompatibility testing confirmed the biological safety of the Sr-CA nanocarrier in mice. These findings suggest that Sr-CA nanocarriers are a promising siRNA delivery system, combining high efficiency with pH-sensitive release and excellent biocompatibility, making them a viable option for future therapeutic applications.

Nanotherapeutic and Nano-Bio Interface for Regeneration and Healing

Wound and injury healing processes are intricate and multifaceted, involving a sequence of events from coagulation to scar tissue formation. Effective wound management is crucial for achieving favorable clinical outcomes. Understanding the cellular and molecular mechanisms underlying wound healing, inflammation, and regeneration is essential for developing innovative therapeutics. This review explored the interplay of cellular and molecular processes contributing to wound healing, focusing on inflammation, innervation, angiogenesis, and the role of cell surface adhesion molecules. Additionally, it delved into the significance of calcium signaling in skeletal muscle regeneration and its implications for regenerative medicine. Furthermore, the therapeutic targeting of cellular senescence for long-term wound healing was discussed. The integration of cutting-edge technologies, such as quantitative imaging and computational modeling, has revolutionized the current approach of wound healing dynamics. The review also highlighted the role of nanotechnology in tissue engineering and regenerative medicine, particularly in the development of nanomaterials and nano-bio tools for promoting wound regeneration. Moreover, emerging nano-bio interfaces facilitate the efficient transport of biomolecules crucial for regeneration. Overall, this review provided insights into the cellular and molecular mechanisms of wound healing and regeneration, emphasizing the significance of interdisciplinary approaches and innovative technologies in advancing regenerative therapies. Through harnessing the potential of nanoparticles, bio-mimetic matrices, and scaffolds, regenerative medicine offers promising avenues for restoring damaged tissues with unparalleled precision and efficacy. This pursuit marks a significant departure from traditional approaches, offering promising avenues for addressing longstanding challenges in cellular and tissue repair, thereby significantly contributing to the advancement of regenerative medicine.

Surface interactions of gelatin-sourced carbon quantum dots with a model globular protein: insights into carbon-based nanomaterials and biological systems

Carbon nanomaterials (CNMs), such as carbon nanotubes (CNTs), graphene quantum dots (GQDs), and carbon quantum dots (CQDs), are prevalent in biological systems and have been widely utilized in applications like environmental sensing and biomedical fields. While their presence in human matrices is projected to increase, the interfacial interactions between carbon-based nanoscopic platforms and biomolecular systems continue to remain underexplored. In this study, we investigated the effect of gelatin-sourced CQDs on the globular milk protein beta-lactoglobulin (BLG). Exposure to the CQDs resulted in the disruption of BLG's tertiary and secondary structural elements (transformation of isolated helices to coiled-coils and increased beta-sheet content), with IR amide backbone signatures further confirming CQD-induced alterations in protein structures. Importantly, the structural perturbations induced by CQDs compromised BLG : retinol interactions, potentially affecting its physiological ligand transport function. By contrast, cytotoxicity analyses revealed a high viability of neuroblastoma cells exposed to this CNM, suggesting biomolecule-specific effects. Collectively, the data reveal aberrant molecular and functional consequences associated with the interactions of a globular protein with an otherwise biocompatible CQD. In conclusion, this work represents the initial steps toward a comprehensive understanding at the atomic and molecular levels of the outcomes linked to the utilization of carbon-based nanomaterials and their potential adverse systemic consequences.

An investigation of the effect of the protein corona on the cellular uptake of nanoliposomes under flow conditions using quartz crystal microgravimetry with dissipation

When nanoparticle delivery systems are immersed in biological fluids, a complex assembly of proteins forms on their surface, creating a protein corona. The protein corona alters the physicochemical properties, toxicity, biodistribution, cellular uptake, and immune response of the nanoparticles, and consequently, their therapeutic efficacy. Currently, there is a lack of in vitro methods to assess the effects of the protein corona on nanoparticle uptake under dynamic flow and assess their binding kinetics in real-time. Here, we introduce quartz crystal microbalance with dissipation (QCM-D) as an in vitro technique, capable of incorporating dynamic flow, to study the effect of the protein corona on the binding of nanoliposome (NLP) formulations to cell surfaces as a first step in their cellular uptake. The interactions of four NLP formulations (low PEGylated, high PEGylated, negatively charged and positively charged NLPs) with A375 melanoma and THP1 cell lines were assessed by QCM-D, before and after the formation of a protein corona. Through real-time recording of the frequency and dissipation shifts (Δf and ΔD, respectively), the QCM-D results provided strong evidence of the role of the protein corona in the cellular interaction of these NLP formulations, with a variation in their adsorption kinetics depending on their initial composition. NLP's attachment to the cell surface was the lowest for PEGylated NLPs (<5%), while the positively charged NLPs showed the highest cellular attachment (≈100%), regardless of the presence of the protein corona or cell type. The effect of the protein corona was more pronounced for the negatively charged NLPs, where a significant reduction in the NLP attachment was observed. To complement the QCM-D data on the NLP attachment and to determine whether the NLP attachment leads to cellular uptake, confocal microscopy and flow cytometry were used to confirm NLP uptake by A375 and THP1 cells. Proteomic analysis revealed a differential composition of the protein corona on the various NLPs with possible implications for their sequestration and cellular uptake. Collectively, the findings suggest that QCM-D can be an important tool to study the binding of NLP formulations or other nanoparticles with cell membranes under dynamic flow, which very often differs from nanoparticle uptake under static conditions.

Effect of Gold Nanoparticles on the Conformation of Bovine Serum Albumin: Insights from CD Spectroscopic Analysis and Molecular Dynamics Simulations

With the development of nanotechnology, there is growing interest in using nanoparticles (NPs) for biomedical applications, such as diagnostics, drug delivery, imaging, and nanomedicine. The protein's structural stability plays a pivotal role in its functionality, and any alteration in this structure can have significant implications, including disease progression. Herein, we performed a combined experimental and computational study of the effect of gold NPs with a diameter of 5 nm (5 nm Au-NPs) on the structural stability of bovine serum albumin (BSA) protein in the absence and presence of NaCl salt. Circular dichroism spectroscopy showed a loss in the secondary structure of BSA due to the synergistic effect of Au-NPs and NaCl, and Thioflavin T fluorescence assays showed suppressed β-sheet formation in the presence of Au-NPs in PBS, emphasizing the intricate interplay between NPs and physiological conditions. Additionally, molecular dynamics (MD) simulations revealed that 5 nm Au-NP induced changes in the secondary structure of the BSA monomer in the presence of NaCl, highlighting the initial binding mechanism between BSA and Au-NP. Furthermore, MD simulations explored the effect of smaller Au-NP (3 nm) and nanocluster (Au-NC with the size of 1 nm) on the binding sites of the BSA monomer. Although the formation of stable BSA-Au conjugates was revealed in the presence of NPs of different sizes, no specific protein binding sites were observed. Moreover, due to its small size, 1 nm Au-NC decreased helical content and hydrogen bonds in the BSA monomer, promoting protein unfolding more significantly. In summary, this combined experimental and computational study provides comprehensive insights into the interactions among Au nanosized substances, BSA, and physiological conditions that are essential for developing tailored nanomaterials with enhanced biocompatibility and efficacy.

Ferroptosis driven by nanoparticles for tackling glioblastoma

Glioblastoma (GBM) is the most aggressive, malignant, and drug-resistant brain tumor. There are no effective treatment options for GBM, which usually leads to relapses that cause patients to die a few months later. Ferroptosis, a newly discovered mechanism of regulated cell death, has been identified as a tumor suppressor in solid tumors and represents an alternative to apoptosis resistance. This mechanism of cell death is characterized by iron overload, which is responsible for generating reactive oxygen species (ROS) in the cell. Understanding the ferroptosis pathway and its key regulators can be used to develop rational delivery systems that specifically target these regulators in GBM cells and promote cell death. This review conducted a systematic literature search to better understand the potential of ferroptosis as a target for developing nanoparticles to tackle GBM. The mechanisms of action, design parameters, efficacy, and safety concerns of 16 nanoparticles were evaluated, demonstrating the potential of combining ferroptosis inducers with nanocarriers to promote a selective delivery to the tumor microenvironment.

Nanostructured zinc carbonate hydroxide microflakes: assessing the toxicity against erythrocytes and L929 cellsin vitro

Nanostructured materials have been suggested to be used as a source of dietary zinc for livestock animals. In this study, we assessed the cytotoxicity of newly synthesized nanostructured zinc carbonate hydroxide (ZnCH) Zn5(CO3)(OH)6microflakes. Cytotoxicity of the microflakes was assessed against murine L929 cell line and rat mature erythrocytes. Viability, motility, cell death pathways, implication of Ca2+, reactive oxygen species and reactive nitrogen species (RNS) signaling, caspases, and alterations of cell membranes following exposure of L929 cells to the microflakes were assessed. To assess hemocompatibility of the Zn-containing microflakes, osmotic fragility and hemolysis assays were performed, as well as multiple eryptosis parameters were evaluated. Our findings indicate a dose-response cytotoxicity of ZnCH microflakes against L929 cells with no toxicity observed for low concentrations (10 mg l-1and below). At high concentrations (25 mg l-1and above), ZnCH microflakes promoted nitrosyl stress, Ca2+- and caspase-dependent apoptosis, and altered lipid order of cell membranes in a dose-dependent manner, evidenced by up to 7-fold elevation of RNS-dependent fluorescence, 2.9-fold enhancement of Fura 2-dependent fluorescence, over 20-fold elevation of caspases-dependent fluorescence (caspase-3, caspase-8, and caspase-9), and up to 4.4-fold increase in the ratiometric index of the NR12S probe. Surprisingly, toxicity to enucleated mature erythrocytes was found to be lower compared to L929 cells. ZnCH microflakes induced eryptosis associated with oxidative stress, nitrosyl stress, Ca2+signaling and recruitment of caspases at 25-50-100 mg l-1. Eryptosis assays were found to be more sensitive than evaluation of hemolysis. Zn5(CO3)(OH)6microflakes show no cytotoxicity at low concentrations indicating their potential as a source of zinc for livestock animals.

Synthesis, Characterization, and Biomedical Applications of Bacteriocin-Selenium Nanoconjugates

The antibiotic overuse in hospitals, the food industry, and animal feed over past times has led to a significant rise in the incidence of antibiotic-resistant bacteria. To address these potentially life-threatening antibiotic-resistant illnesses, a quick identification and development of novel antimicrobials are necessary. The aim of this study was to synthesize a novel bacteriocin-nanoconjugates by combining selenium nanoparticles with purified bacteriocin from the Enterococcus faecium SMAA23 and investigate some of its biomedical activities. The nanoconjugates were characterized via X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray desorption (EDX), and zeta potential analytical techniques. There is investigation of the antibacterial, antifungal, and anticancer properties of nanoconjugates. Purified bacteriocin has a known molecular weight of approximately 43,000 Daltons. The characterization of nanoparticles and nanoconjugates was performed. The crystallite size of nanoconjugate was determined via X-ray diffraction (XRD) to be 15.29 nm. Transmission electron microscopy (TEM) detected particles of irregular form of nanoconjugate, measuring between 11 and 24 nm in diameter. Energy dispersive X-ray spectroscopy (EDX) confirmed the presence of selenium and protein. The measured zeta potential was - 12.1 + 0.12 mV. The results revealed potent antibacterial activity against Acinetobacter baumannii, with a growth inhibition zone of 23 mm ± SD. A minimum inhibitory concentration (MIC) of nanoconjugate was 15.625 µg/mL, while a minimum bactericidal concentration (MBC) was 31.25 µg/mL. The application of scanning electron microscopy (SEM) enhanced the rupture of the bacterial cell wall. The antifungal activity against C. albicans and C. tropicalis resulted in growth inhibition zones of 14 mm and 16 mm (± SD), respectively. Various concentrations of the nanoconjugate strongly inhibited MDA-MB-231 cells in the MTT experiment. The novel synthesized bacteriocin-nanoconjugates exhibited substantial antibacterial, antifungal, and anticancer properties.

Placenta-tropic VEGF mRNA lipid nanoparticles ameliorate murine pre-eclampsia

Pre-eclampsia is a placental disorder that affects 3-5% of all pregnancies and is a leading cause of maternal and fetal morbidity worldwide1,2. With no drug available to slow disease progression, engineering ionizable lipid nanoparticles (LNPs) for extrahepatic messenger RNA (mRNA) delivery to the placenta is an attractive therapeutic option for pre-eclampsia. Here we use high-throughput screening to evaluate a library of 98 LNP formulations in vivo and identify a placenta-tropic LNP (LNP 55) that mediates more than 100-fold greater mRNA delivery to the placenta in pregnant mice than a formulation based on the Food and Drug Administration-approved Onpattro LNP (DLin-MC3-DMA)3. We propose an endogenous targeting mechanism based on β2-glycoprotein I adsorption that enables LNP delivery to the placenta. In both inflammation- and hypoxia-induced models of pre-eclampsia, a single administration of LNP 55 encapsulating vascular endothelial growth factor (VEGF) mRNA resolves maternal hypertension until the end of gestation. In addition, with our VEGF mRNA LNP 55 therapeutic, we demonstrate improvements in fetal health and partially restore placental vasculature, the local and systemic immune landscape and serum levels of soluble Fms-like tyrosine kinase-1, a clinical biomarker of pre-eclampsia1. Together, these results demonstrate the potential of this mRNA LNP platform for treating placental disorders such as pre-eclampsia.

The Photomodification Method Allows for Determining the Composition of the Full and Soft Protein Corona on the Lipid Surface of Composite Nanoparticles

A protein corona (PC) is formed and maintained on the surface of any nanoparticle (NP) introduced into biological media. The full PC is formed by a hard and soft corona, and the latter determines the nature of the interaction of NPs with cells and the body's liquids. Nanomedicines are becoming increasingly important in modern health services, making information about the composition of PCs on the surface of NPs critically important for "managing" the behavior of nano-objects in the body. Currently, only a few studies report on the composition of the complete PC, since the isolation and preservation of the soft corona on the surface of the NP is extremely difficult. Recently, we proposed for the first time a photomodification method to fix PCs on the lipid surface of composite NPs, along with their isolation and purification. In this work, using tandem mass spectrometry, we successively determined the composition of the hard and full corona on the lipid surface of composite NPs, and we also identified the composition of the soft corona. To test the method, we changed the composition of the medium whose proteins formed the soft corona, and we found changes in its composition.

Selective imaging, gene, and therapeutic delivery using PEGylated and pH-Sensitive nanoparticles for enhanced lung disorder treatment

Lung inflammation involves the activation of immune cells and inflammatory mediators in response to injury and infection. When inflammation persists, fibroblasts, which are resident lung cells, become activated, leading to pulmonary fibrosis (PF), abnormal wound healing, and long-term damage to the alveolar epithelium. This persistent inflammation and fibrosis can also elevate the risk of lung cancer, emphasizing the need for innovative treatments. Current therapies, such as inhaled corticosteroids (ICS) and chemotherapy, have significant limitations. Although conventional nanoparticles (NPs) provide a promising avenue for treating lung disorders, they have limited selectivity and stability. Polyethylene glycol (PEG) grafting can prevent NP aggregation and phagocytosis, thus prolonging their circulation time. When combined with targeting ligands, PEGylated NPs can deliver drugs precisely to specific cells or tissues. Moreover, pH-sensitive NPs offer the advantage of selective drug delivery to inflammatory or tumor-acidic environments, reducing side effects. These NPs can change their size, shape, or surface charge in response to pH variations, improving drug delivery efficiency. This review examines the techniques of PEGylation, the polymers used in pH-sensitive NPs, and their therapeutic applications for lung inflammation, fibrosis, and cancer. By harnessing innovative NP technologies, researchers can develop effective therapies for respiratory conditions, addressing unmet medical needs and enhancing patient outcomes.

Supplementation with ions enhances the efficiency of nucleic acid delivery with cell-penetrating peptides

The successful delivery of therapeutic nucleic acids (NAs) into eukaryotic cells is essential for numerous biomedical applications, including gene therapy, gene silencing, and genome editing. Cell-penetrating peptides (CPPs) have claimed significant attention as delivery vehicles due to their inherent ability to penetrate cellular membranes and efficiently transport cargo, including NAs, into the cells. However, further optimization and a deeper understanding of underlying mechanisms are necessary for such transfection methods. Previous studies have demonstrated that Ca2+ ions can significantly enhance NA delivery efficiency when included in transfection media or CPP/NA nanoparticles during preparation. Similar effects have been observed for Mg2+, but the impact of other ions in this context has not been thoroughly investigated. In this study, we supplemented the CPP/NA formulations with various inorganic biocompatible ions by introducing solutions of the respective salts to colloidal nanoparticles at the preparation stage. Our results indicated that supplementing the CPP/NA formulations with certain salt solutions enhanced the biological effect achieved with NAs while also influencing nanoparticle size, surface charge, complexation stability, and, to some extent, the internalization route. Our findings offer valuable insights for optimizing the formation of CPP nanoparticles to improve NA delivery efficiency.

Recent Advances in Simulation Studies on the Protein Corona

When flowing through the blood stream, drug carriers such as nanoparticles encounter hundreds of plasma proteins, forming a protein layer on the nanoparticle surface, known as the "protein corona". Since the protein corona influences the size, shape, and surface properties of nanoparticles, it can modulate their circulating lifetime, cytotoxicity, and targeting efficiency. Therefore, understanding the mechanism of protein corona formation at the atomic scale is crucial, which has become possible due to advances in computer power and simulation methodologies. This review covers the following topics: (1) the structure, dynamics, and composition of protein corona on nanoparticles; (2) the effects of protein concentration and ionic strength on protein corona formation; (3) the effects of particle size, morphology, and surface properties on corona formation; (4) the interactions among lipids, membranes, and nanoparticles with the protein corona. For each topic, mesoscale, coarse-grained, and all-atom molecular dynamics simulations since 2020 are discussed. These simulations not only successfully reproduce experimental observations but also provide physical insights into the protein corona formation. In particular, these simulation findings can be applied to manipulate the formation of a protein corona that can target specific cells, aiding in the rational design of nanomedicines for drug delivery applications.

Navigating Neurotoxicity and Safety Assessment of Nanocarriers for Brain Delivery: Strategies and Insights

Nanomedicine, an area that uses nanomaterials for theragnostic purposes, is advancing rapidly, particularly in the detection and treatment of neurodegenerative diseases. The design of nanocarriers can be optimized to enhance drug bioavailability and targeting to specific organs, improving therapeutic outcomes. However, clinical translation hinges on biocompatibility and safety. Nanocarriers can cross the blood-brain barrier (BBB), potentially causing neurotoxic effects through mechanisms such as oxidative stress, DNA damage, and neuroinflammation. Concerns about their accumulation and persistence in the brain make it imperative to carry out a nanotoxicological risk assessment. Generally, this involves identifying exposure sources and routes, characterizing physicochemical properties, and conducting cytotoxicity assays both in vitro and in vivo. The lack of a specialized regulatory framework creates substantial gaps, making it challenging to translate findings across development stages. Additionally, there is a pressing need for innovative testing methods due to constraints on animal use and the demand for high-throughput screening. This review examines the mechanisms of nanocarrier-induced neurotoxicity and the challenges in risk assessment, highlighting the impact of physicochemical properties and the advantages and limitations of current neurotoxicity evaluation models. Future perspectives are also discussed. Additional guidance is crucial to improve the safety of nanomaterials and reduce associated uncertainty. STATEMENT OF SIGNIFICANCE: Nanocarriers show tremendous potential for theragnostic purposes in neurological diseases, enhancing drug targeting to the brain, and improving biodistribution and pharmacokinetics. However, their neurotoxicity is still a major field to be explored, with only 5% of nanotechnology-related publications addressing this matter. This review focuses on the issue of neurotoxicity and safety assessment of nanocarriers for brain delivery. Neurotoxicity-relevant exposure sources, routes, and molecular mechanisms, along with the impact of the physicochemical properties of nanomaterials, are comprehensively described. Moreover, the different experimental models used for neurotoxicity evaluation are explored at length, including their main advantages and limitations. To conclude, we discuss current challenges and future perspectives for a better understanding of risk assessment of nanocarriers for neurobiomedical applications.

Breaking the final barrier: Evolution of cationic and ionizable lipid structure in lipid nanoparticles to escape the endosome

In the past decade, nucleic acid therapies have seen a boon in development and clinical translation largely due to advances in nanotechnology that have enabled their safe and targeted delivery. Nanoparticles can protect nucleic acids from degradation by serum enzymes and can facilitate entry into cells. Still, achieving endosomal escape to allow nucleic acids to enter the cytoplasm has remained a significant barrier, where less than 5% of nanoparticles within the endo-lysosomal pathway are able to transfer their cargo to the cytosol. Lipid-based drug delivery vehicles, particularly lipid nanoparticles (LNPs), have been optimized to achieve potent endosomal escape, and thus have been the vector of choice in the clinic as demonstrated by their utilization in the COVID-19 mRNA vaccines. The success of LNPs is in large part due to the rational design of lipids that can specifically overcome endosomal barriers. In this review, we chart the evolution of lipid structure from cationic lipids to ionizable lipids, focusing on structure-function relationships, with a focus on how they relate to endosomal escape. Additionally, we examine recent advancements in ionizable lipid structure as well as discuss the future of lipid design.

Mechanisms of extracellular vesicle uptake and implications for the design of cancer therapeutics

The translation of pre-clinical anti-cancer therapies to regulatory approval has been promising, but slower than hoped. While innovative and effective treatments continue to achieve or seek approval, setbacks are often attributed to a lack of efficacy, failure to achieve clinical endpoints, and dose-limiting toxicities. Successful efforts have been characterized by the development of therapeutics designed to specifically deliver optimal and effective dosing to tumour cells while minimizing off-target toxicity. Much effort has been devoted to the rational design and application of synthetic nanoparticles to serve as targeted therapeutic delivery vehicles. Several challenges to the successful application of this modality as delivery vehicles include the induction of a protracted immune response that results in their rapid systemic clearance, manufacturing cost, lack of stability, and their biocompatibility. Extracellular vesicles (EVs) are a heterogeneous class of endogenous biologically produced lipid bilayer nanoparticles that mediate intercellular communication by carrying bioactive macromolecules capable of modifying cellular phenotypes to local and distant cells. By genetic, chemical, or metabolic methods, extracellular vesicles (EVs) can be engineered to display targeting moieties on their surface while transporting specific cargo to modulate pathological processes following uptake by target cell populations. This review will survey the types of EVs, their composition and cargoes, strategies employed to increase their targeting, uptake, and cargo release, and their potential as targeted anti-cancer therapeutic delivery vehicles.

Impact of Protein Coronas on Lipid Nanoparticle Uptake and Endocytic Pathways in Cells

Lipid nanoparticles (LNPs), widely used in disease diagnosis and drug delivery, face the challenge of being surrounded by biological macromolecules such as proteins upon entering the human body. These molecules compete for binding sites on the nanoparticle surfaces, forming a protein corona. The impact of different types of protein coronas on LNP delivery remains unclear. In this study, we employed a newly developed, highly sensitive LNP labeling platform and analyzed the endocytosis of HeLa cells under different nutritional conditions using proteomics to address this critical issue. Our research found that under conditions of complete medium and amino acid starvation, most DNA-FITC vesicles in HeLa cells were located in the perinuclear region 4 h after transfection. In contrast, under serum starvation conditions, only a small portion of DNA-FITC vesicles were in the perinuclear region. On the other hand, through proteomics, we discovered that cells that were enriched in amino acids and complete medium contained more proteins, whereas those under serum starvation had relatively fewer enriched proteins. Through KEGG pathway enrichment analysis, we identified the phagosome and endocytosis pathways as particularly important. Lastly, differential analysis of proteins in these pathways revealed that proteins such as F-actin, Coronin, vATPase, TUBA, TUBB, MHCII, and TSP may have significant impacts on cellular endocytosis. Our research findings indicate that it is necessary to regulate cellular endocytosis based on different protein coronas to achieve optimal cytoplasmic release.

Influence of albumin concentration on surface characteristics and cellular responses in the pre-incubation of multi-walled carbon nanotubes

Reliable characterization of protein coronas (PCs) that form when nanomaterials are introduced into biological fluids is a critical step in the development of safe and efficient nanomedicine. We observed that bovine serum albumin (BSA)-coated multi-walled carbon nanotubes (MWCNTs) do not induce cytotoxicity, but have different cellular uptake rates depending on the BSA pretreatment concentration. To determine how these slight differences affect A549 cell responses and intracellular changes, we conducted spectroscopic (circular dichroism and Fourier-transform infrared) and spectrometric (nanoflow liquid chromatography-electrospray ionization-tandem mass spectrometry) analyses. The various characterization techniques conducted in this study reveal the following. (i) The composition ratio of PCs on MWCNTs differs depending on the BSA concentration. (ii) Analysis of the secondary structure of the proteins revealed that the α-helix structure increased with increasing BSA concentration. (iii) Proteomic analysis showed that different biological pathways were activated at levels higher and lower than 5 mg mL-1. Such combined spectroscopic and spectrometric approaches provide an integrated understanding of PC composition as well as how nano/bio-interface states are linked to cellular-level responses. Our results can support reliable and practical applications of nanomedicine development.

Comprehensive insights into mechanism of nanotoxicity, assessment methods and regulatory challenges of nanomedicines

Nanomedicine has the potential to transform healthcare by offering targeted therapies, precise diagnostics, and enhanced drug delivery systems. The National Institutes of Health has coined the term "nanomedicine" to describe the use of nanotechnology in biological system monitoring, control, diagnosis, and treatment. Nanomedicine continues to receive increasing interest for the rationalized delivery of therapeutics and pharmaceutical agents to achieve the required response while reducing its side effects. However, as nanotechnology continues to advance, concerns about its potential toxicological effects have also grown. This review explores the current state of nanomedicine, focusing on the types of nanoparticles used and their associated properties that contribute to nanotoxicity. It examines the mechanisms through which nanoparticles exert toxicity, encompassing various cellular and molecular interactions. Furthermore, it discusses the assessment methods employed to evaluate nanotoxicity, encompassing in-vitro and in-vivo models, as well as emerging techniques. The review also addresses the regulatory issues surrounding nanotoxicology, highlighting the challenges in developing standardized guidelines and ensuring the secure translation of nanomedicine into clinical settings. It also explores into the challenges and ethical issues associated with nanotoxicology, as understanding the safety profile of nanoparticles is essential for their effective translation into therapeutic applications.

COVID-19 vaccine adverse events: Evaluating the pathophysiology with an emphasis on sulfur metabolism and endotheliopathy

In this narrative review, we assess the pathophysiology of severe adverse events that presented after vaccination with DNA and mRNA vaccines against COVID-19. The focus is on the perspective of an undersulfated and degraded glycocalyx, considering its impact on immunomodulation, inflammatory responses, coagulation and oxidative stress. The paper explores various factors that lead to glutathione and inorganic sulfate depletion and their subsequent effect on glycocalyx sulfation and other metabolites, including hormones. Components of COVID-19 vaccines, such as DNA and mRNA material, spike protein antigen and lipid nanoparticles, are involved in possible cytotoxic effects. The common thread connecting these adverse events is endotheliopathy or glycocalyx degradation, caused by depleted glutathione and inorganic sulfate levels, shear stress from circulating nanoparticles, aggregation and formation of protein coronas; leading to imbalanced immune responses and chronic release of pro-inflammatory cytokines, ultimately resulting in oxidative stress and systemic inflammatory response syndrome. By understanding the underlying pathophysiology of severe adverse events, better treatment options can be explored.

Bridging the gap: Innovative human-based in vitro approaches for nanomaterials hazard assessment and their role in safe and sustainable by design, risk assessment, and life cycle assessment

The application of nanomaterials in industry and consumer products is growing exponentially, which has pressed the development and use of predictive human in vitro models in pre-clinical analysis to closely extrapolate potential toxic effects in vivo. The conventional cytotoxicity investigation of nanomaterials using cell lines from cancer origin and culturing them two-dimensionally in a monolayer without mimicking the proper pathophysiological microenvironment may affect a precise prediction of in vitro effects at in vivo level. In recent years, complex in vitro models (also belonging to the new approach methodologies, NAMs) have been established in unicellular to multicellular cultures either by using cell lines, primary cells or induced pluripotent stem cells (iPSCs), and reconstituted into relevant biological dimensions mimicking in vivo conditions. These advanced in vitro models retain physiologically reliant exposure scenarios particularly appropriate for oral, dermal, respiratory, and intravenous administration of nanomaterials, which have the potential to improve the in vivo predictability and lead to reliable outcomes. In this perspective, we discuss recent developments and breakthroughs in using advanced human in vitro models for hazard assessment of nanomaterials. We identified fit-for-purpose requirements and remaining challenges for the successful implementation of in vitro data into nanomaterials Safe and Sustainable by Design (SSbD), Risk Assessment (RA), and Life Cycle Assessment (LCA). By addressing the gap between in vitro data generation and the utility of in vitro data for nanomaterial safety assessments, a prerequisite for SSbD approaches, we outlined potential key areas for future development.

Serum-derived protein coronas affect nanoparticle interactions with brain cells

Neuronanomedicine is an emerging field bridging the gap between neuromedicine and novel nanotherapeutics. Despite promise, clinical translation of neuronanomedicine remains elusive, possibly due to a dearth of information regarding the effect of the protein corona on these neuronanomedicines. The protein corona, a layer of proteins adsorbed to nanoparticles following exposure to biological fluids, ultimately determines the fate of nanoparticles in biological systems, dictating nanoparticle-cell interactions. To date, few studies have investigated the effect of the protein corona on interactions with brain-derived cells, an important consideration for the development of neuronanomedicines. Here, two polymeric nanoparticles, poly(lactic-co-glycolic acid) (PLGA) and PLGA-polyethylene glycol (PLGA-PEG), were used to obtain serum-derived protein coronas. Protein corona characterization and liquid chromatography mass spectrometry analysis revealed distinct differences in biophysical properties and protein composition. PLGA protein coronas contained high abundance of globins (60%) and apolipoproteins (21%), while PLGA-PEG protein coronas contained fewer globins (42%) and high abundance of protease inhibitors (28%). Corona coated PLGA nanoparticles were readily internalized into microglia and neuronal cells, but not into astrocytes. Internalization of nanoparticles was associated with pro-inflammatory cytokine release and decreased neuronal cell viability, however, viability was rescued in cells treated with corona coated nanoparticles. These results showcase the importance of the protein corona in mediating nanoparticle-cell interactions.

Unlocking the Potential of Silver Nanoparticles: From Synthesis to Versatile Bio-Applications

Silver nanoparticles (AgNPs) are leading the way in nanotechnological innovation, combining the captivating properties of silver with the accuracy of nanoscale engineering, thus revolutionizing material science. Three main techniques arise within the alchemical domains of AgNP genesis: chemical, physical, and biological synthesis. Each possesses its distinct form of magic for controlling size, shape, and scalability-key factors necessary for achieving expertise in the practical application of nanoparticles. The story unravels, describing the careful coordination of chemical reduction, the environmentally sensitive charm of green synthesis utilizing plant extracts, and the precise accuracy of physical techniques. AgNPs are highly praised in the field of healthcare for their powerful antibacterial characteristics. These little warriors display a wide-ranging attack against bacteria, fungi, parasites, and viruses. Their critical significance in combating hospital-acquired and surgical site infections is highly praised, serving as a beacon of hope in the fight against the challenging problem of antibiotic resistance. In addition to their ability to kill bacteria, AgNPs are also known to promote tissue regeneration and facilitate wound healing. The field of cancer has also observed the adaptability of AgNPs. The review documents their role as innovative carriers of drugs, specifically designed to target cancer cells with accuracy, minimizing harm to healthy tissues. Additionally, it explores their potential as cancer therapy or anticancer agents capable of disrupting the growth of tumors. In the food business, AgNPs are utilized to enhance the durability of packing materials and coatings by infusing them with their bactericidal properties. This results in improved food safety measures and a significant increase in the duration that products can be stored, thereby tackling the crucial issue of food preservation. This academic analysis recognizes the many difficulties that come with the creation and incorporation of AgNPs. This statement pertains to the evaluation of environmental factors and the effort to enhance synthetic processes. The review predicts future academic pursuits, envisioning progress that will enhance the usefulness of AgNPs and increase their importance from being new to becoming essential within the realms of science and industry. Besides, AgNPs are not only a subject of scholarly interest but also a crucial component in the continuous effort to tackle some of the most urgent health and conservation concerns of contemporary society. This review aims to explore the complex process of AgNP synthesis and highlight their numerous uses, with a special focus on their growing importance in the healthcare and food business sectors. This review invites the scientific community to explore the extensive possibilities of AgNPs in order to fully understand and utilize their potential.

Optimization of polyethylene glycol shielding and mannose density on the lipid nanoparticles for efficient delivery to macrophages and spleens

This study compared the effects of polyethylene glycol (PEG) shielding and mannose-conjugated ligands density on lipid nanoparticles (LNPs) for intracellular uptake to macrophages in vitro and accumulation in spleens in vivo. Fabricated phosphatidyl serine-incorporated LNPs (sLNPs) was physically decorated with mannose-conjugated DSPE-PEG (DPM) at different DPM/LNP molar ratios achieving the DPM density from 0 to 0.6 PEGs/nm2. We demonstrated that low PEG shielding sLNPs with mannose ligands (sLNP-DPMs) displayed superior uptake to macrophages (RAW 264.7 cells) compared with high PEG shielding sLNP-DPMs in vitro. However, high PEG shielding sLNP-DPMs showed significant spleen accumulation compared with low PEG shielding sLNP-DPMs in vivo after intravenous injection. In particular, high PEG shielding sLNPs coated with DSPE-methoxyPEG (DP) and DPM mixture at DP/DPM molar ratios of 5/5 exhibited greater accumulation in red pulp of spleens than naked sLNPs by 2.7-folds in vivo. These results suggested that the optimal PEG shielding and mannose densities per a particle might be different between in vitro cellular uptake to macrophages and in vivo spleen accumulation after systemic administration. Taken together, precision-tailored LNP-surface modifications achieved through optimization of PEG shielding and mannose density can greatly enhance accumulation of LNPs in red pulp of spleens, which could be applied for the delivery of nucleic acid-based drugs and vaccines to spleens in vivo.

Influence of ionizable lipid tail length on lipid nanoparticle delivery of mRNA of varying length

RNA-based therapeutics have gained traction for the prevention and treatment of a variety of diseases. However, their fragility and immunogenicity necessitate a drug carrier. Lipid nanoparticles (LNPs) have emerged as the predominant delivery vehicle for RNA therapeutics. An important component of LNPs is the ionizable lipid (IL), which is protonated in the acidic environment of the endosome, prompting cargo release into the cytosol. Currently, there is growing evidence that the structure of IL lipid tails significantly impacts the efficacy of LNP-mediated mRNA translation. Here, we optimized IL tail length for LNP-mediated delivery of three different mRNA cargos. Using C12-200, a gold standard IL, as a model, we designed a library of ILs with varying tail lengths and evaluated their potency in vivo. We demonstrated that small changes in lipophilicity can drastically increase or decrease mRNA translation. We identified that LNPs formulated with firefly luciferase mRNA (1929 base pairs) and C10-200, an IL with shorter tail lengths than C12-200, enhance liver transfection by over 10-fold. Furthermore, different IL tail lengths were found to be ideal for transfection of LNPs encapsulating mRNA cargos of varying sizes. LNPs formulated with erythropoietin (EPO), responsible for stimulating red blood cell production, mRNA (858 base pairs), and the C13-200 IL led to EPO translation at levels similar to the C12-200 LNP. The LNPs formulated with Cas9 mRNA (4521 base pairs) and the C9-200 IL induced over three times the quantity of indels compared with the C12-200 LNP. Our findings suggest that shorter IL tails may lead to higher transfection of LNPs encapsulating larger mRNAs, and that longer IL tails may be more efficacious for delivering smaller mRNA cargos. We envision that the results of this project can be utilized as future design criteria for the next generation of LNP delivery systems for RNA therapeutics.

Transepithelial transport of nanoparticles in oral drug delivery: From the perspective of surface and holistic property modulation

Despite the promising prospects of nanoparticles in oral drug delivery, the process of oral administration involves a complex transportation pathway that includes cellular uptake, intracellular trafficking, and exocytosis by intestinal epithelial cells, which are necessary steps for nanoparticles to enter the bloodstream and exert therapeutic effects. Current researchers have identified several crucial factors that regulate the interaction between nanoparticles and intestinal epithelial cells, including surface properties such as ligand modification, surface charge, hydrophilicity/hydrophobicity, intestinal protein corona formation, as well as holistic properties like particle size, shape, and rigidity. Understanding these properties is essential for enhancing transepithelial transport efficiency and designing effective oral drug delivery systems. Therefore, this review provides a comprehensive overview of the surface and holistic properties that influence the transepithelial transport of nanoparticles, elucidating the underlying principles governing their impact on transepithelial transport. The review also outlines the chosen of parameters to be considered for the subsequent design of oral drug delivery systems.

Nanoparticle Isolation from Biological Media for Protein Corona Analysis: The Impact of Incubation and Recovery Protocols on Nanoparticle Properties

Nanoparticles are increasingly implemented in biomedical applications, including the diagnosis and treatment of disease. When exposed to complex biological media, nanoparticles spontaneously interact with their surrounding environment, leading to the surface-adsorption of small and bio- macromolecules- termed the "corona". Corona composition is governed by nanoparticle properties and incubation parameters. While the focus of most studies is on the protein signature of the nanoparticle corona, the impact of experimental protocols on nanoparticle size in the presence of complex biological media, and the impact of nanoparticle recovery from biological media has not yet been reported. Here using a non-degradable robust model, we show how centrifugation-resuspension protocols used for the isolation of nanoparticles from incubation media, incubation duration and shear flow conditions alter nanoparticle parameters including particle size, zeta potential and total protein content. Our results show significant changes in nanoparticle size following exposure to media containing protein under different flow conditions, which also altered the composition of surface-adsorbed proteins profiled by SDS-PAGE. Our in situ analysis of nanoparticle size in media containing protein using particle tracking analysis highlights that centrifugation-resuspension is disruptive to agglomerates that are spontaneously formed in protein containing media, highlighting the need for in situ analytical methods that do not alter the intermediates formed following nanoparticle exposure to biological media. Nanomedicines are mostly intended for parenteral administration, and our findings show that parameters such as shear flow can significantly alter nanoparticle physicochemical parameters. Overall, we show that the centrifugation-resuspension isolation of nanoparticles from media significantly alters particle parameters in addition to the overall protein composition of surface-adsorbed proteins. We recommend that nanoparticle characterization pipelines studying bio-nano interactions during early nanomedicine development consider biologically-relevant shear flow conditions and media composition that can significantly alter particle physical parameters and subsequent conclusions from these studies.

Nanomaterials in Immunology: Bridging Innovative Approaches in Immune Modulation, Diagnostics, and Therapy

The intersection of immunology and nanotechnology has provided significant advancements in biomedical research and clinical applications over the years. Immunology aims to understand the immune system's defense mechanisms against pathogens. Nanotechnology has demonstrated its potential to manipulate immune responses, as nanomaterials' properties can be modified for the desired application. Research has shown that nanomaterials can be applied in diagnostics, therapy, and vaccine development. In diagnostics, nanomaterials can be used for biosensor development, accurately detecting biomarkers even at very low concentrations. Therapeutically, nanomaterials can act as efficient carriers for delivering drugs, antigens, or genetic material directly to targeted cells or tissues. This targeted delivery improves therapeutic efficacy and reduces the adverse effects on healthy cells and tissues. In vaccine development, nanoparticles can improve vaccine durability and extend immune responses by effectively delivering adjuvants and antigens to immune cells. Despite these advancements, challenges regarding the safety, biocompatibility, and scalability of nanomaterials for clinical applications are still present. This review will cover the fundamental interactions between nanomaterials and the immune system, their potential applications in immunology, and their safety and biocompatibility concerns.

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.

A Physiochemical, In Vitro, and In Vivo Comparative Analysis of Verteporfin-Lipid Conjugate Formulations: Solid Lipid Nanoparticles and Liposomes

VisudyneⓇ, a liposomal formulation of verteporfin (benzoporphyrin derivative; BPD), is the only nanomedicine approved to date for photodynamic therapy (PDT). We have previously demonstrated that BPD conjugated to the lysophospholipid 1-arachidoyl-2-hydroxy-sn-glycero-3-phosphocholine (BPD-PC) exhibits the greatest physical stability in liposomes, while maintaining cancer cell phototoxicity, from a panel of BPD lipid conjugates evaluated. In this study, we prepared 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)-based solid lipid nanoparticles (LNPs) that stably entrap BPD-PC, which resemble the composition of the SpikevaxⓇ Moderna COVID-19 vaccine, and compared them to a DPPC based liposomal formulation (Lipo BPD-PC). We evaluated the photochemical, optical, and phototherapeutic properties of both formulations. We also investigated the in vivo distribution and tumor microdistribution of both formulations. Our results demonstrated that Lipo BPD-PC is able to generate 17% more singlet oxygen than LNP BPD-PC, while interestingly, LNP BPD-PC is able to produce 76% more hydroxyl radicals and/or peroxynitrite anion. Importantly, only 28% of BPD-PC leaches out of the LNP BPD-PC formulation during 7 days of incubation in serum at 37 °C, while 100% of BPD-PC leaches out of the Lipo BPD-PC formulation under the same conditions. Despite these differences, there was no significant difference in cellular uptake of BPD-PC or phototoxicity in CT1BA5 murine pancreatic cancer cells (derived from a genetically engineered mouse model). Interestingly, PDT using LNP BPD-PC was more efficient at inducing immunogenic cell death (calreticulin membrane translocation) than Lipo BPD-PC when using IC25 and IC50 PDT doses. In vivo studies revealed that CT1BA5 tumor fluorescence signals from BPD-PC were 2.41-fold higher with Lipo BPD-PC than with LNP BPD-PC; however, no significant difference was observed in tumor tissue selectivity or tumor penetration. As such, we present LNP BPD-PC as a unique and more stable nanoplatform to carry BPD lipid conjugates, such as BPD-PC, with a potential for future photodynamic immune priming studies and multiagent drug delivery.

Overview of in vitro-in vivo extrapolation approaches for the risk assessment of nanomaterial toxicity

Nanomaterials are increasingly used in many applications due to their enhanced properties. To ensure their safety for humans and the environment, nanomaterials need to be evaluated for their potential risk. The risk assessment analysis on the nanomaterials based on animal or in vivo studies is accompanied by several concerns, including animal welfare, time and cost needed for the studies. Therefore, incorporating in vitro studies in the risk assessment process is increasingly considered. To be able to analyze the potential risk of nanomaterial to human health, there are factors to take into account. Utilizing in vitro data in the risk assessment analysis requires methods that can be used to translate in vitro data to predict in vivo phenomena (in vitro-in vivo extrapolation (IVIVE) methods) to be incorporated, to obtain a more accurate result. Apart from the experiments and species conversion (for example, translation between the cell culture, animal and human), the challenge also includes the unique properties of nanomaterials that might cause them to behave differently compared to the same materials in a bulk form. This overview presents the IVIVE techniques that are developed to extrapolate pharmacokinetics data or doses. A brief example of the IVIVE methods for chemicals is provided, followed by a more detailed summary of available IVIVE methods applied to nanomaterials. The IVIVE techniques discussed include the comparison between in vitro and in vivo studies, methods to rene the dose metric or the in vitro models, allometric approach, mechanistic modeling, Multiple-Path Particle Dosimetry (MPPD), methods using organ burden data and also approaches that are currently being developed.

Limits of Non-invasive Enzymatic Activation by Local Temperature Control

Enzymatic activity depends on and can therefore be regulated by temperature. Selective modulation of the activity of different enzymes in one reaction pot would require temperature control local to each type of enzyme. It has been suggested previously that immobilization of enzyme on magnetic nanoparticles and exposing them to alternating magnetic field can enhance the reaction rate. This enhancement has been explained as being mediated by temperature increase caused by dissipation of the absorbed field energy in the form of heat. However, the possibility of spatially limiting this temperature increase on the microscale has been questioned. Here, it is investigated whether an activity enhancement of the enzyme sucrose phosphorylase immobilized on magnetic beads can be achieved, how this effect is related to the increase in temperature, and whether temperature differences within one reaction pot could be generated in this way. It is found that alternating magnetic field stimulation leads to increased enzymatic activity fully attributable to the increase of bulk temperature. Both theoretical analysis and experimental data indicate that no local heating near the particle surface takes place. It is further concluded that relevant increase of surface temperature can be obtained only with macroscopic, millimeter-sized, magnetic particles.

Artificial protein coronas: directing nanoparticles to targets

The protein corona surrounding nanoparticles (NPs) offers exciting possibilities for targeted drug delivery. However, realizing this potential requires direct evidence of corona-receptor interactions in vivo; a challenge hampered by the limitations of in vitro settings. This opinion proposes that utilizing engineered protein coronas can address this challenge. Artificial coronas made of selected plasma proteins retain their properties in vivo, enabling manipulation for specific receptor targeting. To directly assess corona-receptor interactions mimicking in vivo complexity, we propose testing artificial coronas with recently adapted quartz crystal microbalance (QCM) setups whose current limitations and potential advancements are critically discussed. Finally, the opinion proposes future experiments to decipher corona-receptor interactions and unlock the full potential of the protein corona for NP-based drug delivery.

High-Throughput In Vivo Screening Identifies Differential Influences on mRNA Lipid Nanoparticle Immune Cell Delivery by Administration Route

Immune modulation through the intracellular delivery of nucleoside-modified mRNA to immune cells is an attractive approach for in vivo immunoengineering, with applications in infectious disease, cancer immunotherapy, and beyond. Lipid nanoparticles (LNPs) have come to the fore as a promising nucleic acid delivery platform, but LNP design criteria remain poorly defined, making the rate-limiting step for LNP discovery the screening process. In this study, we employed high-throughput in vivo LNP screening based on molecular barcoding to investigate the influence of LNP composition on immune tropism with applications in vaccines and systemic immunotherapies. Screening a large LNP library under both intramuscular (i.m.) and intravenous (i.v.) injection, we observed differential influences on LNP uptake by immune populations across the two administration routes, gleaning insight into LNP design criteria for in vivo immunoengineering. In validation studies, the lead LNP formulation for i.m. administration demonstrated substantial mRNA translation in the spleen and draining lymph nodes with a more favorable biodistribution profile than LNPs formulated with the clinical standard ionizable lipid DLin-MC3-DMA (MC3). The lead LNP formulations for i.v. administration displayed potent immune transfection in the spleen and peripheral blood, with one lead LNP demonstrating substantial transfection of splenic dendritic cells and another inducing substantial transfection of circulating monocytes. Altogether, the immunotropic LNPs identified by high-throughput in vivo screening demonstrated significant promise for both locally- and systemically-delivered mRNA and confirmed the value of the LNP design criteria gleaned from our screening process, which could potentially inform future endeavors in mRNA vaccine and immunotherapy applications.

Unlocking Transplant Tolerance with Biomaterials

For patients suffering from organ failure due to injury or autoimmune disease, allogeneic organ transplantation with chronic immunosuppression is considered the god standard in terms of clinical treatment. However, the true "holy grail" of transplant immunology is operational tolerance, in which the recipient exhibits a sustained lack of alloreactivity toward unencountered antigen presented by the donor graft. This outcome is resultant from critical changes to the phenotype and genotype of the immune repertoire predicated by the activation of specific signaling pathways responsive to soluble and mechanosensitive cues. Biomaterials have emerged as a medium for interfacing with and reprogramming these endogenous pathways toward tolerance in precise, minimally invasive, and spatiotemporally defined manners. By viewing seminal and contemporary breakthroughs in transplant tolerance induction through the lens of biomaterials-mediated immunomodulation strategies-which include intrinsic material immunogenicity, the depot effect, graft coatings, induction and delivery of tolerogenic immune cells, biomimicry of tolerogenic immune cells, and in situ reprogramming-this review emphasizes the stunning diversity of approaches in the field and spotlights exciting future directions for research to come.

Physicochemical Targeting of Lipid Nanoparticles to the Lungs Induces Clotting: Mechanisms and Solutions

Lipid nanoparticles (LNPs) have become the dominant drug delivery technology in industry, holding the promise to deliver RNA to up or down-regulate any protein of interest. LNPs have mostly been targeted to specific cell types or organs by physicochemical targeting in which LNP's lipid compositions are adjusted to find mixtures with the desired tropism. Here lung-tropic LNPs are examined, whose organ tropism derives from containing either a cationic or ionizable lipid conferring a positive zeta potential. Surprisingly, these LNPs are found to induce massive thrombosis. Such thrombosis is shown in the lungs and other organs, and it is shown that it is greatly exacerbated by pre-existing inflammation. This clotting is induced by a variety of formulations with cationic lipids, including LNPs and non-LNP nanoparticles, and even by lung-tropic ionizable lipids that do not have a permanent cationic charge. The mechanism depends on the LNPs binding to and then changing the conformation of fibrinogen, which then activates platelets and thrombin. Based on these mechanisms, multiple solutions are engineered that enable positively charged LNPs to target the lungs while ameliorating thrombosis. The findings illustrate how physicochemical targeting approaches must be investigated early for risks and re-engineered with a careful understanding of biological mechanisms.

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.

Green synthesis of yeast cell wall-derived carbon quantum dots with multiple biological activities

Hypothesis

Yeast cell walls are a sustainable biomass source containing carbon and other elements like phosphorus. Converting cell walls into valuable nanomaterials like carbon quantum dots (CQDs) is of interest.

Experiments

Cell walls from Saccharomyces cerevisiae were hydrothermally treated in 0.5 M H2SO4 to produce CQDs. Multiple analytical techniques were utilized to confirm phosphorus-doping (P-CQDs), characterize the fluorescence properties, determine quantum yield, and evaluate the sensing, antimicrobial, photocatalytic, and antioxidant capacities.

Findings

A successful synthesis of P-CQDs was achieved with strong blue fluorescence under UV excitation, 19 % quantum yield, and excellent stability. The P-CQDs showed sensitive fluorescence quenching in response to ferric ions with a 201 nM detection limit. Antibacterial effects against Escherichia coli and Staphylococcus aureus were demonstrated. P-CQDs also exhibited dye degradation under sunlight and antioxidant activity. So, the prepared P-CQDs displayed promising multifunctional capabilities for metal ion detection, disinfection, and environmental remediation. Further research is required to fully realize and implement the multifunctional potential of P-CQDs in real-world applications.

Surface ligand-regulated renal clearance of MRI/SPECT dual-modality nanoprobes for tumor imaging

BACKGROUND

The general sluggish clearance kinetics of functional inorganic nanoparticles tend to raise potential biosafety concerns for in vivo applications. Renal clearance is a possible elimination pathway for functional inorganic nanoparticles delivered through intravenous injection, but largely depending on the surface physical chemical properties of a given particle apart from its size and shape.

RESULTS

In this study, three small-molecule ligands that bear a diphosphonate (DP) group, but different terminal groups on the other side, i.e., anionic, cationic, and zwitterionic groups, were synthesized and used to modify ultrasmall Fe3O4 nanoparticles for evaluating the surface structure-dependent renal clearance behaviors. Systematic studies suggested that the variation of the surface ligands did not significantly increase the hydrodynamic diameter of ultrasmall Fe3O4 nanoparticles, nor influence their magnetic resonance imaging (MRI) contrast enhancement effects. Among the three particle samples, Fe3O4 nanoparticle coated with zwitterionic ligands, i.e., Fe3O4@DMSA, exhibited optimal renal clearance efficiency and reduced reticuloendothelial uptake. Therefore, this sample was further labeled with 99mTc through the DP moieties to achieve a renal-clearable MRI/single-photon emission computed tomography (SPECT) dual-modality imaging nanoprobe. The resulting nanoprobe showed satisfactory imaging capacities in a 4T1 xenograft tumor mouse model. Furthermore, the biocompatibility of Fe3O4@DMSA was evaluated both in vitro and in vivo through safety assessment experiments.

CONCLUSIONS

We believe that the current investigations offer a simple and effective strategy for constructing renal-clearable nanoparticles for precise disease diagnosis.

Unraveling the impact of nanopollution on plant metabolism and ecosystem dynamics

Nanopollution (NPOs), a burgeoning consequence of the widespread use of nanoparticles (NPs) across diverse industrial and consumer domains, has emerged as a critical environmental issue. While extensive research has scrutinized the repercussions of NPs pollution on ecosystems and human health, scant attention has been directed towards unraveling its implications for plant life. This comprehensive review aims to bridge this gap by delving into the nuanced interplay between NPOs and plant metabolism, encompassing both primary and secondary processes. Our exploration encompasses an in-depth analysis of the intricate mechanisms governing the interaction between plants and NPs. This involves a thorough examination of how physicochemical properties such as size, shape, and surface characteristics influence the uptake and translocation of NPs within plant tissues. The impact of NPOs on primary metabolic processes, including photosynthesis, respiration, nutrient uptake, and water transport. Additionally, this study explored the multifaceted alterations in secondary metabolism, shedding light on the synthesis and modulation of secondary metabolites in response to NPs exposure. In assessing the consequences of NPOs for plant life, we scrutinize the potential implications for plant growth, development, and environmental interactions. The intricate relationships revealed in this review underscore the need for a holistic understanding of the plant-NPs dynamics. As NPs become increasingly prevalent in ecosystems, this investigation establishes a fundamental guide that underscores the importance of additional research to shape sustainable environmental management strategies and address the extensive effects of NPs on the development of plant life and environmental interactions.

Cutting-edge approaches for targeted drug delivery in breast cancer: beyond conventional therapies

Breast cancer is a global health challenge with staggering statistics underscoring its pervasive impact. The burden of this disease is measured in terms of its prevalence and the challenges it poses to healthcare systems, necessitating a closer look at its epidemiology and impact. Current breast cancer treatments, including surgery, chemotherapy, radiation therapy, and targeted therapies, have made significant strides in improving patient outcomes. However, they are not without limitations, often leading to adverse effects and the development of drug resistance. This comprehensive review delves into the complex landscape of breast cancer, including its incidence, current treatment modalities, and the inherent limitations of existing therapeutic approaches. It also sheds light on the promising role of nanotechnology, encompassing both inorganic and organic nanoparticles equipped with the ability to selectively deliver therapeutic agents to tumor sites, in the battle against breast cancer. The review also addresses the emerging therapies, their associated challenges, and the future prospects of targeted drug delivery in breast cancer management.

Decoding Nanomaterial-Biosystem Interactions through Machine Learning

The interactions between biosystems and nanomaterials regulate most of their theranostic and nanomedicine applications. These nanomaterial-biosystem interactions are highly complex and influenced by a number of entangled factors, including but not limited to the physicochemical features of nanomaterials, the types and characteristics of the interacting biosystems, and the properties of the surrounding microenvironments. Over the years, different experimental approaches coupled with computational modeling have revealed important insights into these interactions, although many outstanding questions remain unanswered. The emergence of machine learning has provided a timely and unique opportunity to revisit nanomaterial-biosystem interactions and to further push the boundary of this field. This minireview highlights the development and use of machine learning to decode nanomaterial-biosystem interactions and provides our perspectives on the current challenges and potential opportunities in this field.

Molecular Ballet: Investigating the Complex Interaction between Self-Assembling Dendrimers and Human Serum Albumin via Computational and Experimental Methods

Dendrimers, intricate macromolecules with highly branched nanostructures, offer unique attributes including precise control over size, shape, and functionality, making them promising candidates for a wide range of biomedical applications. The exploration of their interaction with biological environments, particularly human serum albumin (HSA), holds significant importance for biomedical utilization. In this study, the interaction between HSA and a recently developed self-assembling amphiphilic dendrimer (AD) was investigated using various experimental techniques. Fluorescence spectroscopy and isothermal titration calorimetry revealed moderate interactions between the protein and the AD nanomicelles (NMs), primarily attributed to favorable enthalpic contributions arising from electrostatic interactions and hydrogen bonding. Structural analysis indicated minimal changes in HSA upon complexation with the AD NMs, which was further supported by computational simulations demonstrating stable interactions at the atomistic level. These findings provide valuable insights into the binding mechanisms and thermodynamic parameters governing HSA/AD NM interactions, thereby contributing to the understanding of their potential biomedical applications.

Fluorine-modified polymers reduce the adsorption of immune-reactive proteins to PEGylated gold nanoparticles

Aim: To investigate the influence of fluorine in reducing the adsorption of immune-reactive proteins onto PEGylated gold nanoparticles. Methods: Reversible addition fragmentation chain transfer polymerization, the Turkevich method and ligand exchange were used to prepare polymer-coated gold nanoparticles. Subsequent in vitro physicochemical and biological characterizations and proteomic analysis were performed. Results: Fluorine-modified polymers reduced the adsorption of complement and other immune-reactive proteins while potentially improving circulatory times and modulating liver toxicity by reducing apolipoprotein E adsorption. Fluorine actively discouraged phagocytosis while encouraging the adsorption of therapeutic targets, CD209 and signaling molecule calreticulin. Conclusion: This study suggests that the addition of fluorine in the surface coating of nanoparticles could lead to improved performance in nanomedicine designed for the intravenous delivery of cargos.

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.

Personalized Cancer Nanomedicine: Overcoming Biological Barriers for Intracellular Delivery of Biopharmaceuticals

The success of personalized medicine in oncology relies on using highly effective and precise therapeutic modalities such as small interfering RNA (siRNA) and monoclonal antibodies (mAbs). Unfortunately, the clinical exploitation of these biological drugs has encountered obstacles in overcoming intricate biological barriers. Drug delivery technologies represent a plausible strategy to overcome such barriers, ultimately facilitating the access to intracellular domains. Here, an overview of the current landscape on how nanotechnology has dealt with protein corona phenomena as a first and determinant biological barrier is presented. This continues with the analysis of strategies facilitating access to the tumor, along with conceivable methods for enhanced tumor penetration. As a final step, the cellular barriers that nanocarriers must confront in order for their biological cargo to reach their target are deeply analyzed. This review concludes with a critical analysis and future perspectives of the translational advances in personalized oncological nanomedicine.

Emerging strategies for nanomedicine in autoimmunity

Autoimmune disorders have risen to be among the most prevalent chronic diseases across the globe, affecting approximately 5-7% of the population. As autoimmune diseases steadily rise in prevalence, so do the number of potential therapeutic strategies to combat them. In recent years, fundamental research investigating autoimmune pathologies has led to the emergence of several cellular targets that provide new therapeutic opportunities. However, key challenges persist in terms of accessing and specifically combating the dysregulated, self-reactive cells while avoiding systemic immune suppression and other off-target effects. Fortunately, the continued advancement of nanomedicines may provide strategies to address these challenges and bring innovative autoimmunity therapies to the clinic. Through precise engineering and rational design, nanomedicines can possess a variety of physicochemical properties, surface modifications, and cargoes, allowing for specific targeting of therapeutics to pathological cell and organ types. These advances in nanomedicine have been demonstrated in cancer therapies and have the broad potential to advance applications in autoimmunity therapies as well. In this review, we focus on leveraging the power of nanomedicine for prevalent autoimmune disorders throughout the body. We expand on three key areas for the development of autoimmunity therapies - avoiding systemic immunosuppression, balancing interactions with the immune system, and elevating current platforms for delivering complex cargoes - and emphasize how nanomedicine-based strategies can overcome these barriers and enable the development of next-generation, clinically relevant autoimmunity therapies.

Overcoming the Low-Stability Bottleneck in the Clinical Translation of Liposomal Pressurized Metered-Dose Inhalers: A Shell Stabilization Strategy Inspired by Biomineralization

Currently, several types of inhalable liposomes have been developed. Among them, liposomal pressurized metered-dose inhalers (pMDIs) have gained much attention due to their cost-effectiveness, patient compliance, and accurate dosages. However, the clinical application of liposomal pMDIs has been hindered by the low stability, i.e., the tendency of the aggregation of the liposome lipid bilayer in hydrophobic propellant medium and brittleness under high mechanical forces. Biomineralization is an evolutionary mechanism that organisms use to resist harsh external environments in nature, providing mechanical support and protection effects. Inspired by such a concept, this paper proposes a shell stabilization strategy (SSS) to solve the problem of the low stability of liposomal pMDIs. Depending on the shell material used, the SSS can be classified into biomineralization (biomineralized using calcium, silicon, manganese, titanium, gadolinium, etc.) biomineralization-like (composite with protein), and layer-by-layer (LbL) assembly (multiple shells structured with diverse materials). This work evaluated the potential of this strategy by reviewing studies on the formation of shells deposited on liposomes or similar structures. It also covered useful synthesis strategies and active molecules/functional groups for modification. We aimed to put forward new insights to promote the stability of liposomal pMDIs and shed some light on the clinical translation of relevant products.

Fe3O4SPIONs in cancer theranostics-structure versus interactions with proteins and methods of their investigation

As the second leading cause of death worldwide, neoplastic diseases are one of the biggest challenges for public health care. Contemporary medicine seeks potential tools for fighting cancer within nanomedicine, as various nanomaterials can be used for both diagnostics and therapies. Among those of particular interest are superparamagnetic iron oxide nanoparticles (SPIONs), due to their unique magnetic properties,. However, while the number of new SPIONs, suitably modified and functionalized, designed for medical purposes, has been gradually increasing, it has not yet been translated into the number of approved clinical solutions. The presented review covers various issues related to SPIONs of potential theranostic applications. It refers to structural considerations (the nanoparticle core, most often used modifications and functionalizations) and the ways of characterizing newly designed nanoparticles. The discussion about the phenomenon of protein corona formation leads to the conclusion that the scarcity of proper tools to investigate the interactions between SPIONs and human serum proteins is the reason for difficulties in introducing them into clinical applications. The review emphasizes the importance of understanding the mechanism behind the protein corona formation, as it has a crucial impact on the effectiveness of designed SPIONs in the physiological environment.