Mechanistic understanding of in vivo protein corona formation on polymeric nanoparticles and impact on pharmacokinetics

Investigation of the protein corona and biodistribution profile of polymeric nanoparticles for intra-amniotic delivery

When exposed to the biological environment, nanoparticles (NPs) form a protein corona that influences delivery profile. We present a study of protein corona formation and NP biodistribution in amniotic fluid (AF) for poly(lactic-co-glycolic acid) (PLGA) and poly(lactic-acid) (PLA) NPs, with and without polyethylene glycol (PEG), as well as poly(amine-co-ester)-PEG (PACE-PEG) NPs. The presence of surface PEG and polyvinyl alcohol (PVA) were characterized to investigate surfactant role in determining protein corona formation. The surface density of PEG groups demonstrated an inverse correlation with the total amount of protein surface adsorption. All PEGylated NPs exhibited a dense brush conformation and demonstrated higher levels of stability in AF than non-PEGylated NPs. The protein corona composition varied by core polymer, while the amount of protein adsorption varied by PEGylation status. In A549 cells, in vitro cellular association of each NP type correlated with the amount of albumin that was found in the protein corona. In vivo, only PEGylated NPs were able successfully distribute to fetal organs, likely due to the enhanced stability imparted by PEG. PLGA-PEG and PACE-PEG NPs had both high levels of albumin in the protein corona and high biodistribution to the fetal lung, consistent with the association with lung cells in vitro. PLA-PEG NPs distributed exclusively to the fetal bowel, which we propose is associated with known gastrointestinal targeting keratin proteins. By furthering our understanding of polymeric NP behavior in AF, this novel study provides a basis for optimization of intra-amniotic NP delivery systems targeting congenital pulmonary and gastrointestinal diseases.

Nanomedicine for targeting brain Neurodegeneration: Critical barriers and circadian rhythm Considerations

The development of novel therapies for central nervous system (CNS) diseases, particularly neurodegenerative disorders like Alzheimer's disease (AD), is a critical global health priority. Biotherapeutics, such as monoclonal antibodies (mAbs) and RNA-based therapies, have shown potential for treating brain disorders. However, their clinical progress is limited by their difficult access to their brain targets. At the preclinical level, nanotechnology has been shown, to help these molecules overcome the biological barriers that imped their adequate brain delivery. This review highlights advances in this area and the challenges for the translation to the clinic. Key nanotechnology-based strategies, such as surface modifications utilizing endogenous protein corona, functionalization with targeting ligands, therapeutic ultrasound-mediated microbubble oscillation were particularly analyzed. Additionally, in line with the focus of the Special Issue, this review integrates the concept of chronotherapy, with a focus on AD treatment, highlighting the idea that, by aligning nanoparticle (NP)-based drug delivery with circadian rhythms, it may be possible to improve therapeutic outcomes. Finally, the article analyzes current strategies in CNS drug delivery in clinical trials and provides future directions within this frame, notably in the area of AD.

Multilayered Nanoarchitectonics of Poly(ethylene glycol) Nanoparticles with Tunable Stiffness Modulate Bio-Nano Interactions and Targeted Drug Delivery

Stiffness, as a crucial physicochemical property of nanoparticles (NPs), has demonstrated a significant impact on bio-nano interactions, including blood circulation, biodistribution, tumor accumulation, and cellular uptake. However, the potential role of NP stiffness in modulating bio-nano interactions to potentiate drug delivery efficacy remains largely unexplored. In this study, poly(ethylene glycol) (PEG) NPs are engineered by the sophisticated layer-by-layer (LbL) assembly approach, and the Young's moduli of NPs in the range of 2-31 kPa are tuned by control over the bilayer numbers. Notably, softer PEG NPs resulted in less adsorption of the protein corona and cell association. The half-life of blood circulation time of PEG NPs decreases along with the increase in stiffness/bilayer number of NPs, while the accumulation of PEG NPs in the liver is contrary to the case. In addition, stiffness influences the targeted drug delivery efficacy, where softer PEG NPs modified with hyaluronic acid exhibited higher cell targeting and tumor accumulation as well as better inhibition of tumor growth. This work highlights the bilayer number-mediated stiffness of NPs and the vital role of stiffness in bio-nano interactions, which provides a promising approach to design nanocarriers for improved drug delivery efficacy.

Direct Quantification of PEGylation for Intact Bioconjugates and Nanoparticles by the Colorimetric Barium/Iodide Assay

Several methods are available to determine the average number of methoxy poly(ethylene glycol) (mPEG) chains grafted to a protein or peptide, referred to as the degree of PEGylation. Nevertheless, the development of simple, versatile, and multiplexable methods for determining PEGylation remains desirable. Childs and Kurfürst have respectfully reported the quantitative and qualitative use of a colored 'barium-iodide-PEG' complex for the titration of PEG in solutions and to stain PEG-containing bands on electrophoresis gels. Remarkably, this assay has yet to be employed to directly determine the extent of PEGylation of protein bioconjugates or intact nanoparticles. This study validates this assay for these purposes, via libraries of 54 mPEG-protein conjugates and 10 polymeric nanoparticles. The effect of mPEG molecular weight, terminal functional groups, and architecture were analyzed, among other parameters. Practical details and known artifacts are discussed to enhance the accuracy and reproducibility of the assay.

Modified sodium caseinate-based nanomicelles for enhanced chemotherapeutics against breast cancer via improved cellular uptake and cytotoxicity

OBJECTIVE

Poor prognosis, drug resistance, and lower drug loading capacity of the delivery systems lead to therapeutic failures of breast cancers. Herein, we functionalized sodium caseinate nanomicelles (NaCNs) with the divalent calcium (Ca2+) and the glucose (Glc) to increase the loading capacity of micelles for higher cellular uptake and cytotoxicity against breast cancer cells.

METHODOLOGY

Modification of casein micelles was confirmed through Fourier transform infrared spectra (FTIR). Triple quadrupole liquid chromatography-mass spectrometry (TQOF-LCMS/MS) was utilized as a simple, rapid, and sensitive method for protein corona quantification around casein through SwissProt.Mus_musculus database and through de novo sequencing. Un-modified and modified casein micelles were further characterized through field emission scanning electron microscope (FESEM), high resolution-transmission electron microscope (HR-TEM), and energy-dispersive X-ray (EDX). Whereas, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used for protein separation and analysis during micelles formation.

RESULTS

Calcium divalent modified sodium caseinate nanomicelles (Ca-NaCNs) and glucose-modified sodium caseinate nanomicelles (Glc-NaCNs) were successfully developed, demonstrating a significantly improved micellar stability. Glc-NaCNs-DOX showed a zeta size of 297.13 ± 15.66 nm with an improved zeta potential of -13.73 ± 0.579 with a drug loading efficiency (DLE) of 86% as compared to our previously published casein formulations since the modified versions involved more soluble casein in the protein micelle matrix, Whereas, Ca-NaCNs-DOX also showed an IC50 value of approximately 197.1 nm as compared to IC50 of free DOX (341.8 nm) and when compared to unmodified DOX loaded formulations (p < .001).

CONCLUSION

Modified NaCNs exhibit the potential to be investigated further as a novel delivery system for similar active moieties to maximize their therapeutic effects.

Machine Learning Reveals Amine Type in Polymer Micelles Determines mRNA Binding, In Vitro, and In Vivo Performance for Lung-Selective Delivery

Cationic micelles, composed of amphiphilic block copolymers with polycationic coronas, offer a customizable platform for mRNA delivery. Here, we present a library of 30 cationic micelle nanoparticles (MNPs) formulated from diblock copolymers with reactive poly(pentafluorophenol acrylate) backbones modified with diverse amines. This library systematically varies in nitrogen-based cationic functionalities, exhibiting a spectrum of properties that encompass varied degrees of alkyl substitution (A1-A5), piperazine (A6), oligoamine (A7), guanidinium (A8), and hydroxylation (A9-A10) that vary in side-chain volume, substitution pattern, hydrophilicity, and pK a to assess parameter impact on mRNA delivery. In vitro delivery assays using GFP+ mRNA across multiple cell lines reveal that amine side-chain bulk and chemical structure critically affect performance. Using machine learning analysis via SHapley Additive exPlanations (SHAP) on 180 formulations (3780 experimental measurements), we mapped key relationships between amine chemistry and performance metrics, finding that amine-specific binding efficiency was a major determinant of mRNA delivery efficacy, cell viability, and GFP intensity. Micelles with stronger mRNA binding capabilities (A1 and A7) have higher cellular delivery performance, whereas those with intermediate binding tendencies deliver a higher amount of functional mRNA per cell (A2, A10). This indicates that balancing the binding strength is crucial for performance. Micelles with hydrophobic and bulky pendant groups (A3-A5) tend to induce necrosis during cellular delivery, highlighting the significance of chemical optimization. A7 amphiphile, displaying primary and secondary amine, consistently demonstrates the highest GFP expression across various cell types and in vivo achieves high delivery specificity to lung tissue upon intravenous administration. Moreover, we established a strong correlation between in vitro and in vivo performance using Multitask Gaussian Process models, underscoring the predictive power of in vitro models for anticipating in vivo outcomes. Overall, this innovative study integrates advanced data science with experimental design, demonstrating the pivotal role of chemical amine-dependent optimization for advancing targeted mRNA delivery to the lungs.

Targeting Polymeric Nanoparticles to Specific Cell Populations in the Liver

Nanoparticles (NPs) are beneficial for delivery of drugs in a variety of settings, serving to protect their cargo and allow for sustained release. Polymeric NPs offer several advantages as therapeutics carriers due to their tunable characteristics like size and shape, ease of manufacturing, and biocompatibility. Despite this, there are no polymeric NPs that are approved for treatment of liver diseases. This is surprising since─when administered intravenously─the majority of NPs accumulate in cells in the liver. NP characteristics like size and surface charge can be altered to affect distribution to the liver, and even cellular distribution, but the conjugation of targeting ligands onto the NP surface for specific receptors on the cells is an important approach for enhancing cell specific delivery. Enhancing cell-specific targeting of conjugated NPs in the liver has two major hurdles: 1) avoiding accumulation of NPs in the liver resident macrophages known as Kupffer cells, which are optimized to phagocytose particulates, and 2) overcoming the transport barriers associated with architectural changes of the diseased liver. To identify the structures and mechanisms most important in NP design, NP administration during ex vivo perfusion (EVP)─achieved by anatomically isolating an organ by perfusing it outside the body─may be the most important and efficient approach. However, EVP is currently underutilized in the NP field, with limited research published on NPs delivered during liver EVP, and therefore representing an opportunity for future investigations.

Development of Thermostable and Immunogenic Block Copolymer Nanoparticles (BNPs) for mRNA Delivery

Combining an amphiphilic block copolymer polybutadiene-b-poly(ethylene glycol) (PBD-b-PEO), an ionizable lipid, a helper lipid, and cholesterol produces thermostable BNPs. Luciferase mRNA-BNPs can be stored for over 1 year at 4 °C with no evidence of degradation to the mRNA or nanocarrier. In vivo, mRNA-BNPs exhibit a greater affinity for secondary lymphoid organs than mRNA-lipid nanoparticles (LNPs) and are efficiently taken up by macrophages and dendritic cells. Freshly fabricated ovalbumin (OVA) mRNA-BNPs elicit robust OVA-specific IgG and functional memory CD8+ T cells that persist for at least 5 months. Immunogenicity remains intact after 24 weeks of storage at 4 °C. Anti-PEG antibodies are not boosted by the repeated administration of mRNA-BNPs, unlike mRNA-LNPs. Syrian hamsters vaccinated with SARS-CoV-2 spike mRNA-BNPs are protected against weight loss associated with infection and potently suppress pulmonary viral loads. Protective efficacy is comparable to that conferred by a Comirnaty biosimilar. Cumulatively, mRNA-BNPs are thermostable, immunogenic and possess the potential for clinical application.

Poly(amino acid) nanoformulation of cyclin-dependent kinase 4 and 6 inhibitor for molecularly targeted immunotherapy in triple-negative breast cancer

Cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6is) selectively arrest malignant cells in the G1 phase of cell cycle by inhibiting CDK4/6-mediated phosphorylation of retinoblastoma protein. However, CDK4/6i therapy is often ineffective against triple-negative breast cancer (TNBC) due to the high lysosomal content in TNBC cells, which sequesters the drugs and prevents them from reaching their nuclear target. To address this challenge, three pH- and glutathione-responsive poly(amino acid) nanogels composed of methoxy poly(ethylene glycol) of various lengths and poly(L-glutamic acid-co-L-cystine) (mPEG-P(Glu10-co-Cys25)) were developed to efficiently deliver the CDK4/6i abemaciclib (ABE) to TNBC cells. These nanogels bypassed lysosomal sequestration, thereby enhancing the efficacy of molecularly targeted immunotherapy. Among the nanogels, the formulation with mPEG2000 (NG2000) exhibited the highest efficiency in delivering ABE, resulting in increased cell apoptosis, activation of an anti-cancer immune response, reduction of immunosuppression, and improved therapeutic outcomes against TNBC. Furthermore, NG2000/ABE enhanced immune checkpoint therapy for TNBC, achieving a tumor inhibition rate of 89.66%. These findings demonstrate the potential of poly(amino acid) nanoformulations for delivering CDK4/6 inhibitors as molecularly targeted immunotherapy for TNBC in clinical applications.

Top-Down Proteomic Profiling of Protein Corona by High-Throughput Capillary Isoelectric Focusing-Mass Spectrometry

In the rapidly evolving field of nanomedicine, understanding the interactions between nanoparticles (NPs) and biological systems is crucial. A pivotal aspect of these interactions is the formation of a protein corona when NPs are exposed to biological fluids (e.g., human plasma), which significantly influences their behavior and functionality. This study introduces an advanced capillary isoelectric focusing tandem mass spectrometry (cIEF-MS/MS) platform designed to enable high-throughput and reproducible top-down proteomic analysis of protein corona. Our cIEF-MS/MS technique completed each analysis within 30 min. It produced reproducible proteoform measurements of protein corona for at least 50 runs regarding the proteoforms' migration time [relative standard deviations (RSDs) <4%], the proteoforms' intensity (Pearson's correlation coefficients between any two runs >0.90), the number of proteoform identifications (71 ± 10), and the number of proteoform-spectrum matches (PrSMs) (196 ± 30). Of the 53 identified genes, 33 are potential biomarkers of various diseases (e.g., cancer, cardiovascular disease, and Alzheimer's disease). We identified 1-102 proteoforms per potential protein biomarker, containing various sequence variations or post-translational modifications. Delineating proteoforms in protein corona by our cIEF-MS/MS in a reproducible and high-throughput fashion will benefit our understanding of nanobiointeractions and advance both diagnostic and therapeutic nanomedicine technologies.

Transfection via RNA-Based Nanoparticles: Comparing Encapsulation vs Adsorption Approaches of RNA Incorporation

Historically, RNA delivery via nanoparticles has primarily relied on encapsulation, as demonstrated by lipid nanoparticles in SARS-CoV-2 vaccines. Concerns about RNA degradation on nanoparticle surfaces initially limited the exploration of adsorption-based approaches. However, recent advancements have renewed interest in adsorption as a viable alternative. This Viewpoint explores the approaches of RNA incorporation in nanoparticles, comparing encapsulation, adsorption, and the combination of encapsulation and adsorption, and presents a framework to guide the selection of the most suitable strategy based on general characteristics.

Nanomedicine Innovations for Lung Cancer Diagnosis and Therapy

Lung cancer remains a challenge within the realm of oncology. Characterized by late-stage diagnosis and resistance to conventional treatments, the currently available therapeutic strategies encompass surgery, radiotherapy, chemotherapy, immunotherapy, and biological therapy; however, overall patient survival remains suboptimal. Nanotechnology has ushered in a new era by offering innovative nanomaterials with the potential to precisely target cancer cells while sparing healthy tissues. It holds the potential to reshape the landscape of cancer management, offering hope for patients and clinicians. The assessment of these nanotechnologies follows a rigorous evaluation process similar to that applied to chemical drugs, which includes considerations of their pharmacokinetics, pharmacodynamics, toxicology, and clinical effectiveness. However, because of the characteristics of nanoparticles, standard toxicological tests require modifications to accommodate their unique characteristics. Effective therapeutic strategies demand a profound understanding of the disease and consideration of clinical outcomes, physicochemical attributes of nanomaterials, nanobiointeractions, nanotoxicity, and regulatory compliance to ensure patient safety. This review explores the promise of nanomedicine in lung cancer treatment by capitalizing on its unique physicochemical properties. We address the multifaceted challenges of lung cancer and its tumor microenvironment and provide an overview of recent developments in nanoplatforms for early diagnosis and treatment that can enhance patient outcomes and overall quality of life.

Nanoparticle-based drug delivery systems to modulate tumor immune response for glioblastoma treatment

Glioblastoma (GBM) is a primary central nervous system neoplasm, characterized by a grim prognosis and low survival rates. This unfavorable therapeutic outcome is partially attributed to the inadequate immune infiltration and an immunosuppressive microenvironment, which compromises the effectiveness of conventional radiotherapy and chemotherapy. To this end, precise modulation of cellular dynamics in the immune system has emerged as a promising approach for therapeutic intervention. The advent of nanoparticle-based therapies has revolutionized cancer treatment and provided highly effective options. Consequently, various strategically designed nano-delivery platforms have been established to promote the efficacy of immune therapy against GBM. This review delves into the recent advancements in nano-based delivery systems that are designed to modulate immune cells in GBM microenvironment, and explores their multifaceted mechanisms, including the blockade of immune checkpoints, the restraint of immunosuppressive cells, the coordination of tumor-associated macrophages, the activation of innate immune cells, and the stimulation of adaptive immunity. Collectively, this summary not only advances the comprehension involved in modulating antitumor immune responses in GBM, but also paves the way for the development of innovative therapeutic strategies to conquer GBM. STATEMENT OF SIGNIFICANCE: Glioblastoma (GBM) is the most lethal brain tumor, with a median survival rate of merely 12-16 months after diagnosis. Despite surgical, radiation and chemotherapy treatments, the two-year survival rate for GBM patients is less than 10 %. The treatment of GBM is challenging mainly because several issues associated with the GBM microenvironment have not yet been resolved. Most recently, novel drug delivery approaches, based on the clear understanding of the intrinsic properties of GBM, have shown promise in overcoming some of the obstacles. In particular, taking account of the highly immunosuppressive tumor microenvironment in GBM, recent advancements in nano-based delivery systems are put forward to stimulate immune cells in GBM and unravel their multifaceted mechanisms. This review summarizes the latest nanoparticle-based drug delivery systems to modulate tumor immune response for glioblastoma treatment. Moreover, the development trends and challenges of nanoparticle-based drug delivery systems in modulating the immunity of GBM are predicted, which may facilitate widespread regimens springing up for successfully treating GBM.

Extreme Tolerance of Nanoparticle-Protein Corona to Ultra-High Abundance Proteins Enhances the Depth of Serum Proteomics

The serum nanoparticle-protein corona (NPC) provides specific disease information, thus opening a new avenue for high-throughput in-depth proteomics to facilitate biomarker discovery. Yet, little is known about the interactions between NPs and proteins, and its role in enhanced depth of serum proteomics. Herein, a series of protein spike-in experiments are conducted to systematically investigate protein depletion and enrichment during NPC formation. Proteomic depth is serum concentration-dependent, and NPC exhibits powerful tolerance to ultra-high abundant proteins. In addition, protein-protein interactions (PPI), especially those involving albumin, play a pivotal role in promoting proteomic depth. Furthermore, a triple-protein assay is established to interrogate the relationship between protein binding affinity and concentration. NPC formation is a product of balancing binding affinity, concentration, and PPI. Overall, this study elucidates how NPs achieve protein depletion and enrichment for enhanced serum proteomic depth to gain a better understanding of NPC as an essential tool of proteome profiling.

Emerging strategies against accelerated blood clearance phenomenon of nanocarrier drug delivery systems

Nanocarrier drug delivery systems (NDDS) have gained momentum in the field of anticancer or nucleic acid drug delivery due to their capacity to aggrandize the targeting efficacy and therapeutic outcomes of encapsulated drugs. A disadvantage of NDDS is that repeated administrations often encounter an obstacle known as the "accelerated blood clearance (ABC) phenomenon". This phenomenon results in the rapid clearance of the secondary dose from the bloodstream and markedly augmented liver accumulation, which substantially undermines the accurate delivery of drugs and the therapeutic effect of NDDS. Nevertheless, the underlying mechanism of this phenomenon has not been elucidated and there is currently no effective method for its eradication. In light of the above, the aim of this review is to provide a comprehensive summary of the underlying mechanism and potential countermeasures of the ABC phenomenon, with a view to rejuvenating both the slow-release property and expectation of NDDS in the clinic. In this paper, we innovatively introduce the pharmacokinetic mechanism of ABC phenomenon to further elucidate its occurrence mechanism after discussing its immunological mechanism, which provides a new direction for expanding the mechanistic study of ABC phenomenon. Whereafter, we conducted a critical conclusion of potential strategies for the suppression or prevention of the ABC phenomenon in terms of the physical and structural properties, PEG-lipid derivatives, dosage regimen and encapsulated substances of nanoformulations, particularly covering some novel high-performance nanomaterials and mixed modification methods. Alternatively, we innovatively propose a promising strategy of applying the characteristics of ABC phenomenon, as the significantly elevated hepatic accumulation and activated CYP3A1 profile associated with the ABC phenomenon are proved to be conducive to enhancing the efficacy of NDDS in the treatment of hepatocellular carcinoma. Collectively, this review is instructive for surmounting or wielding the ABC phenomenon and advancing the clinical applications and translations of NDDS.

PEGylated solid lipid nanoparticles for the intranasal delivery of combination antiretroviral therapy composed of Atazanavir and Elvitegravir to treat NeuroAIDS

Intranasal drug administration offers a promising strategy for delivering combination antiretroviral therapy (cART) directly to the central nervous system to treat NeuroAIDS, leveraging the nose-to-brain route to bypass the blood-brain barrier. However, challenges such as enzymatic degradation in the nasal mucosa, low permeability, and mucociliary clearance within the nasal cavity must first be addressed to make this route feasible. To overcome these barriers, this study developed solid lipid nanoparticles (SLNs) with varying PEGylation levels (0 %, 5 %, 10 %, and 15 % w/w of PEGylated lipid), co-encapsulated with Elvitegravir (EVG) and Atazanavir (ATZ) as an integrase and protease inhibitor, respectively. Pre-formulation studies confirmed the compatibility of the drugs with the excipients. Characterization showed that PEGylation reduces SLN size by approximately up to 12 % while maintaining monodispersity and a high encapsulation efficiency of over 99 % for both EVG and ATZ in their amorphous forms. Incubation of the formulations in artificial nasal mucus revealed that increased PEGylation consistently reduces nanoparticle aggregation and mean aggregate size, suggesting improved SLN stability in the mucus. Importantly, higher PEGylation levels significantly enhanced model drug permeability across the nasal mucus barrier by up to 10-fold. Lastly, cellular uptake studies using the RPMI 2650 nasal epithelial cell line indicated that PEGylation does not reduce nanoparticle uptake rates. These findings highlight the potential of PEGylated SLNs as an effective vehicle for enhancing the intranasal delivery of cART to treat NeuroAIDS. However, further in vivo studies are needed to confirm the brain targeting potential of this formulation.

Engineering the physical characteristics of biomaterials for innate immune-mediated cancer immunotherapy

It has recently been recognized that the physical characteristics of biomaterials - such as size, structure, shape, charge, mechanical strength, hydrophobicity, and multivalency - regulate immunological functions in innate immune cells. In immuno-oncology applications, biomaterials are engineered with distinct physical properties to achieve desired innate immune responses. In this review, we discuss how physical characteristics influence effector functions and innate immune signaling pathways in distinct innate immune cell subtypes. We highlight how physical properties of biomaterials impact phagocytosis regulation, biodistribution, and innate immune cell targeting. We outline the recent advances in physical engineering of biomaterials that directly or indirectly induce desired innate immune responses for cancer immunotherapy. Lastly, we discuss the challenges in current biomaterial approaches that need to be addressed to improve clinical applicability.

Nanoparticle Association with Brain Cells Is Augmented by Protein Coronas Formed in Cerebrospinal Fluid

Neuronanomedicine harnesses nanoparticle technology for the treatment of neurological disorders. An unavoidable consequence of nanoparticle delivery to biological systems is the formation of a protein corona on the nanoparticle surface. Despite the well-established influence of the protein corona on nanoparticle behavior and fate, as well as FDA approval of neuro-targeted nanotherapeutics, the effect of a physiologically relevant protein corona on nanoparticle-brain cell interactions is insufficiently explored. Indeed, less than 1% of protein corona studies have investigated protein coronas formed in cerebrospinal fluid (CSF), the fluid surrounding the brain. Herein, we utilize two clinically relevant polymeric nanoparticles (PLGA and PLGA-PEG) to evaluate the formation of serum and CSF protein coronas. LC-MS analysis revealed distinct protein compositions, with selective enrichment/depletion profiles. Enhanced association of CSF precoated particles with brain cells demonstrates the importance of selecting physiologically relevant biological fluids to more accurately study protein corona formation and subsequent nanoparticle-cell interactions, paving the way for improved nanoparticle engineering for in vivo applications.

Ligand-free biodegradable poly(beta-amino ester) nanoparticles for targeted systemic delivery of mRNA to the lungs

Non-viral nanoparticles (NPs) have seen heightened interest as a delivery method for a variety of clinically relevant nucleic acid cargoes in recent years. While much of the focus has been on lipid NPs, non-lipid NPs, including polymeric NPs, have the possibility of improved efficacy, safety, and targeting, especially to non-liver organs following systemic administration. A safe and effective systemic approach for intracellular delivery to the lungs could overcome limitations to intratracheal/intranasal delivery of NPs and improve clinical benefit for a range of diseases including cystic fibrosis. Here, engineered biodegradable poly (beta-amino ester) (PBAE) NPs are shown to facilitate efficient delivery of mRNA to primary human airway epithelial cells from both healthy donors and individuals with cystic fibrosis. Optimized NP formulations made with differentially endcapped PBAEs and systemically administered in vivo lead to high expression of mRNA within the lungs in BALB/c and C57 B/L mice without requiring a complex targeting ligand. High levels of mRNA-based gene editing were achieved in an Ai9 mouse model across bronchial, epithelial, and endothelial cell populations. No toxicity was observed either acutely or over time, including after multiple systemic administrations of the NPs. The non-lipid biodegradable PBAE NPs demonstrate high levels of transfection in both primary human airway epithelial cells and in vivo editing of lung cell types that are targets for numerous life-limiting diseases particularly single gene disorders such as cystic fibrosis and surfactant deficiencies.

Dual responsive drug-loaded nanomotor based on zwitterionic materials for the treatment of peritoneal metastatic cancer

Innovative treatments for peritoneal metastatic cancer have attracted widespread attention from researchers. Here, we propose a drug-loaded nanomotor (PSBMA/l-Arg/DOX, PLD) based on zwitterionic materials for the treatment of peritoneal metastatic cancer through intraperitoneal injection. Zwitterionic polymer nanocarriers (PSBMA NPs) are obtained by radical polymerization with zwitterionic SBMA as the polymerization monomer and N,N'-Bis(acryloyl)cystamine (BAC) as the cross-linking agent. The zwitterionic substrate of this nanomotor has the ability to resist non-specific protein adsorption in ascites. The loaded l-arginine enables the nanomotor to have the ability to chemotaxis towards high concentrations of ROS/iNOS in tumors and be catalyzed to produce NO, achieving deep penetration into tumor tissue. Furthermore, the disulfide bond (SS) carried by the crosslinking agent used in the preparation of the nanomotor can respond to the high expression of reducing glutathione in the tumor microenvironment and undergo degradation, releasing a large amount of loaded drug DOX. Cell and animal disease model experiments confirme the good therapeutic effect of this drug-loaded nanomotor, providing new therapeutic concepts and strategies for the treatment of peritoneal metastatic cancer.

Drug delivery systems based on mesoporous silica nanoparticles for the management of hepatic diseases

The liver performs multiple life-sustaining functions. Hepatic diseases, including hepatitis, cirrhosis, and hepatoma, pose significant health and economic burdens globally. Along with the advances in nanotechnology, mesoporous silica nanoparticles (MSNs) exhibiting diversiform size and shape, distinct morphological properties, and favorable physico-chemical features have become an ideal choice for drug delivery systems and inspire alternative thinking for the management of hepatic diseases. Initially, we introduce the physiological structure of the liver and highlight its intrinsic cell types and correlative functions. Next, we detail the synthesis methods and physicochemical properties of MSNs and their capacity for controlled drug loading and release. Particularly, we discuss the interactions between liver and MSNs with respect to the passive targeting mechanisms of MSNs within the liver by adjusting their particle size, pore diameter, surface charge, hydrophobicity/hydrophilicity, and surface functionalization. Subsequently, we emphasize the role of MSNs in regulating liver pathophysiology, exploring their value in addressing liver pathological states, such as tumors and inflammation, combined with multi-functional designs and intelligent modes to enhance drug targeting and minimize side effects. Lastly, we put forward the problems, challenges, opportunities, as well as clinical translational issues faced by MSNs in the management of liver diseases.

Double Peptide-Functionalized Carboxymethyl Chitosan-Coated Liposomes Loaded with Dexamethasone as a Potential Strategy for Active Targeting Drug Delivery

Liposomes are intensively used as nanocarriers for biology, biochemistry, medicine, and in the cosmetics industry and their non-toxic and biocompatible nature makes these vesicles attractive systems for biomedical applications. Moreover, the conjugation of specific ligands to liposomes increases their cellular uptake and therapeutic efficiency. Considering these aspects, the aim of the present study was to obtain new formulations of cationic liposomes coated with dual-peptide functionalized carboxymethyl chitosan (CMCS) for the treatment of inner ear diseases. In order to achieve efficient active targeting and ensuring a high efficacy of the treatment, CMCS was functionalized with Tet1 peptide, to target specific ear cells, and TAT peptide, to ensure cellular penetration. Furthermore, dexamethasone phosphate was loaded as a model drug for the treatment of ear inflammation. The infrared spectroscopy confirmed the functionalization of CMCS with the two specific peptides. The mean diameter of the uncovered liposomes varied between 167 and 198 nm whereas the CMCS-coated liposomes ranged from 179 to 202 nm. TEM analysis showed the spherical shape and unilamellar structure of liposomes. The release efficiency of dexamethasone phosphate after 24 h from the uncoated liposomes was between 37 and 40% and it appeared that the coated liposomes modulated this release. The obtained results demonstrated that the liposomes are hemocompatible since, for a tested concentration of 100 µg/mL, the liposome suspension had a lysis of erythrocytes lower than 2.5% after 180 min of incubation. In addition, the peptide-functionalized CMCS-coated liposomes induced a non-significant effect on the viability of normal V79-4 cells after 48 h, at the highest doses. Values of 71.31% were recorded (CLCP-1), 77.28% (CLCP-2) and 74.36% (CLCP-3), correlated with cytotoxic effects of 28.69%, 22.72%, and 25.64%.

Effect of PEGylation on the Adsorption and Binding Strength of Plasma Proteins to Nanoparticle Surfaces

The adsorption of plasma proteins (human serum albumin, immunoglobulin γ-1, apolipoproteins A-I and E-III) onto polystyrene surfaces grafted with polyethylene glycol (PEG) at different grafting densities is simulated using an all-atom PEG model validated by comparing the conformations of isolated PEG chains with previous simulation and theoretical values. At high PEG density, the grafted PEG chains extend like brushes, while at low density, they significantly adsorb to the surface due to electrostatic attraction between polystyrene amines and PEG oxygens, forming a PEG layer much thinner than its Flory radius. Free energy calculations show that PEGylation can either increase or decrease the binding strength between proteins and surfaces, to an extent dependent on PEG density and specific proteins involved, in agreement with experiments. In particular, grafted PEG chains not only sterically block the binding between proteins and surfaces but also strongly interact with proteins via hydrogen bonds and electrostatic and hydrophobic interactions, with apolipoproteins exhibiting stronger hydrophobic interactions with PEG than other proteins, implying that these specific protein-PEG interactions help certain proteins remain on the PEGylated surface. These simulation findings help explain experimental observations regarding the abundance of specific plasma proteins adsorbed onto nanoparticles grafted with PEG at different densities.

Development of a Cationic Polymeric Micellar Structure with Endosomal Escape Capability Enables Enhanced Intramuscular Transfection of mRNA-LNPs

Background/Objectives: The endosomal escape of lipid nanoparticles (LNPs) is crucial for efficient mRNA-based therapeutics. Here, we present a cationic polymeric micelle (cPM) as a safe and potent co-delivery system with enhanced endosomal escape capabilities. Methods: We synthesized a cationic and ampholytic di-block copolymer, poly (poly (ethylene glycol)4-5 methacrylatea-co-hexyl methacrylateb)X-b-poly(butyl methacrylatec-co-dimethylaminoethyl methacrylated-co-propyl acrylatee)Y (p(PEG4-5MAa-co-HMAb)X-b-p(BMAc-co-DMAEMAd-co-PAAe)Y), via reversible addition-fragmentation chain transfer polymerization. The cPMs were then formulated using the synthesized polymer by the dispersion-diffusion method and characterized by dynamic light scattering (DLS) and cryo-transmission electron microscopy (CryoTEM). The membrane-destabilization activity of the cPMs was evaluated by a hemolysis assay. We performed an in vivo functional assay of firefly luciferase (Fluc) mRNA using two of the most commonly studied LNPs, SM102 LNP and Dlin-MC3-DMA LNPs. Results: With a particle size of 61.31 ± 0.68 nm and a zeta potential of 37.76 ± 2.18 mV, the cPMs exhibited a 2-3 times higher firefly luciferase signal at the injection site compared to the control groups without cPMs following intramuscular injection in mice, indicating the high potential of cPMs to enhance the endosomal escape efficiency of mRNA-LNPs. Conclusions: The developed cPM, with enhanced endosomal escape capabilities, presents a promising strategy to improve the expression efficiency of delivered mRNAs. This approach offers a novel alternative strategy with no modifications to the inherent properties of mRNA-LNPs, preventing any unforeseeable changes in formulation characteristics. Consequently, this polymer-based nanomaterial holds immense potential for clinical applications in mRNA-based vaccines.

Precisely Controlling the Activation of an Iron-Locked Drug Generator in the Liver Sinusoid to Enhance Barrier Penetration and Reduction of Liver Fibrosis

Complex physical barriers and the nanomaterial's clearance mechanism in the liver greatly hinder the feasibility of using a conventional liver-targeting nanoplatform to deliver antifibrotic drugs to pathological sites for the treatment of liver fibrosis. Here, a novel drug delivery strategy was designed to overcome drug penetration barriers in a fibrotic liver and cooperated with oral nattokinase (NKase)-mediated antifibrosis therapy as a proof of concept, which relies on the coadministration of a nanosized iron-locked drug generator (named Pro-HAase) and orally absorbed iron chelator deferasirox (DFX). Such a strategy starts from the rapid accumulation of intravenously injected Pro-HAase in the microcapillaries of the fibrotic liver followed by disrupting the polyphenol-iron coordination inside Pro-HAase by DFX, liberating antifibrotic components, including procyanidine (PA) and hyaluronidase (HAase). Attractively, absorption of DFX requires the sequential processes of traversing the intestinal mucosa and targeting the liver, which enable DFX to preferentially disassemble Pro-HAase accumulated in the liver sinusoid rather than in systemic circulation or other organs, thus avoiding the off-target activation of Pro-HAase and depletion of the normal iron pool. The in situ disassembly process decreases the sequestration of Pro-HAase by cells of the mononuclear phagocyte system and promotes gradient-driven permeation of therapeutic components to surrounding liver tissues within 2 h, accompanied by biliary excretion of the inactive iron-DFX complex. As a result, the cooperation of Pro-HAase and DFX not only allows NKase-mediated therapy to completely reverse liver fibrosis but also suppresses the chronic hepatotoxicity of residual liver iron after multiple doses of Pro-HAase. The high spatiotemporal precision, unique barrier-penetration mechanism, and self-detoxification ability of this strategy will inspire the rational design of analogous iron-locked nanosystems to improve the therapeutic outcomes of liver fibrosis or other liver diseases.

Pathophysiology-Driven Approaches for Overcoming Nanomedicine Resistance in Pancreatic Cancer

Tumor heterogeneity poses a significant challenge in cancer therapy. To address this, we analyze pharmacotherapeutic challenges by categorizing them into static and dynamic barriers, reframing these challenges to improve drug delivery, efficacy, and the development of controlled-release nanomedicines (CRNMs). This pathophysiology-driven approach facilitates the design of novel therapeutics tailored to overcome obstacles in pancreatic ductal adenocarcinoma (PDAC) using nanotechnology. Advanced biomaterials in nanodrug delivery systems offer innovative solutions by combining controlled release, stimuli sensitivity, and smart design strategies. CRNMs are engineered to modulate spatiotemporal signaling and control drug release in PDAC, where resistance to conventional therapies is particularly high. This review explores pharmacokinetic considerations for nanomedicine design, RNA interference (RNAi) for stromal modulation, and the development of targeted nanomedicine strategies. Additionally, we highlight the limitations of current animal models in capturing the complexities of PDAC and discuss notable clinical failures, such as PEGylated hyaluronidase (Phase III HALO 109-301 trial) and evofosfamide (TH-302) with gemcitabine (MAESTRO trial), underscoring the need for improved models and treatment strategies. By targeting pathways like Notch and Hedgehog and incorporating stimuli-sensitive and pathway-modulating agents, CRNMs offer a promising avenue to enhance drug penetration and efficacy, reshaping the paradigm of pancreatic cancer treatment.

Safety Landscape of Therapeutic Nanozymes and Future Research Directions

Oxidative stress and inflammation are at the root of a multitude of diseases. Treatment of these conditions is often necessary but current standard therapies to fight excessive reactive oxygen species (ROS) and inflammation are often ineffective or complicated by substantial safety concerns. Nanozymes are emerging nanomaterials with intrinsic enzyme-like properties that hold great promise for effective cancer treatment, bacterial elimination, and anti-inflammatory/anti-oxidant therapy. While there is rapid progress in tailoring their catalytic activities as evidenced by the recent integration of single-atom catalysts (SACs) to create next-generation nanozymes with superior activity, selectivity, and stability, a better understanding and tuning of their safety profile is imperative for successful clinical translation. This review outlines the current applied safety assessment approaches and provides a comprehensive summary of the safety knowledge of therapeutic nanozymes. Overall, nanozymes so far show good in vitro and in vivo biocompatibility despite considerable differences in their composition and enzymatic activities. However, current safety investigations mostly cover a limited set of basic toxicological endpoints, which do not allow for a thorough and deep assessment. Ultimately, remaining research gaps that should be carefully addressed in future studies are highlighted, to optimize the safety profile of therapeutic nanozymes early in their pre-clinical development.

Emerging nanoprobes for the features visualization of vulnerable atherosclerotic plaques

Atherosclerosis (AS) is a major cause of cardiovascular disease. In particular, the unpredictable rupture of vulnerable atherosclerotic plaques (VASPs) can cause serious cardiovascular events such as myocardial infarction, stroke, and even sudden death. Therefore, early evaluation of the vulnerability of atherosclerotic plaques is of great importance. However, clinical imaging techniques are only marginally useful in the presence of severe anatomical structural changes, making it difficult to evaluate plaque vulnerability at an early stage. With the development of molecular imaging and nanotechnology, specific nanoprobes constructed for the pathological features of VASPs have attracted much attention for their ability to visualize VASPs early and noninvasively at the cellular and molecular levels. Here, we outline the pathological features of VASPs, analyze the superiority and limitations of current clinical imaging techniques, introduce the rational design principles of nanoprobes, and systematically summarize the application of nanoprobes to visualize the features of VASPs at the cellular and molecular levels. In addition, we discussed the prospects and urgent challenges in this field, and we believe it will provide new ideas for the early and accurate diagnosis of cardiovascular diseases.

Omics-Enhanced Nanomedicine for Cancer Therapy

Cancer nanomedicine has emerged as a promising approach to overcome the limitations of conventional cancer therapies, offering enhanced efficacy and safety in cancer management. However, the inherent heterogeneity of tumors presents increasing challenges for the application of cancer nanomedicine in both diagnosis and treatment. This heterogeneity necessitates the integration of advanced and high-throughput analytical techniques to tailor nanomedicine strategies to individual tumor profiles. Omics technologies, encompassing genomics, epigenomics, transcriptomics, proteomics, metabolomics, and more, provide unparalleled insights into the molecular and cellular mechanisms underlying cancer. By dissecting tumor heterogeneity across multiple levels, these technologies offer robust support for the development of personalized and precise cancer nanomedicine strategies. In this review, the principles, techniques, and applications of key omics technologies are summarized. Especially, the synergistic integration of omics and nanomedicine in cancer therapy is explored, focusing on enhanced diagnostic accuracy, optimized therapeutic strategies and the assessment of nanomedicine-mediated biological responses. Moreover, this review addresses current challenges and outlines future directions in the field of omics-enhanced nanomedicine. By offering valuable insights and guidance, this review aims to advance the integration of omics with nanomedicine, ultimately driving improved diagnostic and therapeutic strategies for cancer.

pH and Redox Dual-Responsive Nanoparticle with Enhanced Dendritic Cell Maturation for Cancer Therapy

Type I interferons (IFNs) are essential for activating dendritic cells (DCs) and presenting tumor-associated antigens to T cells. IFNs are primarily produced from DCs among immune cells. A combination of chemotherapy and metalloimmunotherapy induces IFN production by activating the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway. However, chemotherapeutic agents deplete DC populations, suppressing immunostimulatory activities, despite their potent anticancer activities. Furthermore, an optimal ratio between chemotherapeutic agents and metal for activating DCs at the highest level has not been reported, and evidence for ensuring DC survival is lacking. In this study, we hypothesized that there is an optimal ratio to yield the highest DC maturation and anticancer activity with minimal DC depletion. To demonstrate it, we have designed a pH and redox dual-responsive nanoparticle, MnO2@BSA@DOX (MD), to prevent DCs from depleting and activate the cGAS-STING pathway both in cancer cells and DCs, inducing considerable levels of IFNs and maturation. MD consists of a core-layer structure, a manganese dioxide (MnO2) core, and a cross-linked layer with bovine serum albumin (BSA) and doxorubicin (DOX), with a specific ratio of DOX to manganese. MD exhibits structure-based selectivity between cancer cells and DCs by targeting the extracellular pH of the tumor microenvironment and intracellular redox reactions in cancer cells. Among various formulations, the 1:1 ratio shows the highest maturation with no significant depletion. Moreover, it induces distinct cytotoxicity in cancer cells through apoptosis and cGAS-STING activation, leading to increased calreticulin expression and enhanced DC phagocytosis. Consequently, it results in superior tumor suppression and prolonged survival with the high accumulation of MD in the tumor and no observed systemic toxicities, highlighting its potential as a therapeutic agent in cancer treatments.

Post-Sterilization Physicochemical Characterization and Biological Activity of Cellulose Nanocrystals Coated with PDDA

The rapid expansion of medical nanotechnology has significantly broadened the potential applications of cellulose nanocrystals (CNCs). While CNCs were initially developed for drug delivery, they are now being investigated for a range of advanced biomedical applications. As these applications evolve, it becomes crucial to understand the physicochemical behavior of CNCs in biologically relevant media to optimize their design and ensure biocompatibility. Functionalized CNCs can adsorb biomolecules, forming a "protein corona" that can impact their physicochemical properties, including alterations in particle size, zeta potential, and overall functionality. In this study, CNCs were coated with low (8500 Da)- and high (400,000-500,000 Da)-molecular-weight cationic polymer (poly(diallyldimethylammonium chloride-(PDDA) via non-covalent grafting, and their physicochemical characteristics, as well as their biological effects, were assessed in physiologically relevant media after sterilization. Our findings show that autoclaving significantly alters the physicochemical properties of CNC-PDDA, particularly when coated with low-molecular-weight (LMW) polymer. Furthermore, we observed that CNC-PDDA of a high molecular weight (HMW) has a greater impact on cell viability and blood biocompatibility than its LMW counterpart. Moreover, cellular immune responses to both CNC-PDDA LMW and HMW vary in the presence or absence of serum, implying that protein adsorption influences cell-nanomaterial recognition and their biological activity. This study provides valuable insights for optimizing CNC-based nanomaterials for therapeutic applications.

In situ characterization techniques of protein corona around nanomaterials

Nanoparticles (NPs) inevitably interact with proteins upon exposure to biological fluids, leading to the formation of an adsorption layer known as the "protein corona". This corona imparts NPs with a new biological identity, directly influencing their interactions with living systems and dictating their fates in vivo. Thus, gaining a comprehensive understanding of the dynamic interplay between NPs and proteins in biological fluids is crucial for predicting therapeutic effects and advancing the clinical translation of nanomedicines. Numerous methods have been established to decode the protein corona fingerprints. However, these methods primarily rely on prior isolation of NP-protein complex from the surrounding medium by centrifugation, resulting in the loss of outer-layer proteins that directly interact with the biological system and determine the in vivo fate of NPs. We discuss here separation techniques as well as in situ characterization methods tailored for comprehensively unraveling the inherent complexities of NP-protein interactions, highlighting the challenges of in situ protein corona characterization and its significance for nanomedicine development and clinical translation.

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.

Nanoparticle-based approaches for treating restenosis after vascular injury

Percutaneous coronary intervention (PCI) is currently the main method for treating coronary artery stenosis, but the incidence of restenosis after PCI is relatively high. Restenosis, the narrowing of blood vessels by more than 50% of the normal diameter after PCI, severely compromises the therapeutic efficacy. Therefore, preventing postinterventional restenosis is important. Vascular restenosis is mainly associated with endothelial injury, the inflammatory response, the proliferation and migration of vascular smooth muscle cells (VSMCs), excessive deposition of extracellular matrix (ECM) and intimal hyperplasia (IH) and is usually prevented by administering antiproliferative or anti-inflammatory drugs through drug-eluting stents (DESs); however, DESs can lead to uncontrolled drug release. In addition, as extracorporeal implants, they can cause inflammation and thrombosis, resulting in suboptimal treatment. Therefore, there is an urgent need for a drug carrier with controlled drug release and high biocompatibility for in vivo drug delivery to prevent restenosis. The development of nanotechnology has enabled the preparation of nanoparticle drug carriers with low toxicity, high drug loading, high biocompatibility, precise targeting, controlled drug release and excellent intracellular delivery ability. This review summarizes the advantages of nanoparticle drug carriers for treating vascular restenosis, as well as how nanoparticles have improved targeting, slowed the release of therapeutic agents, and prolonged circulation in vivo to prevent vascular restenosis more effectively. The overall purpose of this review is to present an overview of nanoparticle therapy for vascular restenosis. We expect these findings to provide insight into nanoparticle-based therapeutic approaches for vascular restenosis.

Protein Corona of Nanoparticles: Isolation and Analysis

Nanoparticles entering biological systems or fluids inevitably adsorb biomolecules, such as protein, on their surfaces, forming a protein corona. Ensuing, the protein corona endows nanoparticles with a new biological identity and impacts the interaction between the nanoparticles and biological systems. Hence, the development of reliable techniques for protein corona isolation and analysis is key for understanding the biological behaviors of nanoparticles. First, this review systematically outlines the approach for isolating the protein corona, including centrifugation, magnetic separation, size exclusion chromatography, flow-field-flow fractionation, and other emerging methods. Next, we review the qualitative and quantitative characterization methods of the protein corona. Finally, we underscore the necessary steps to advance the efficiency and fidelity of protein corona isolation and characterization on nanoparticle surfaces. We anticipate that these insights into protein corona isolation and characterization methodologies will profoundly influence the development of technologies aimed at elucidating bionano interactions and the role of protein corona in various biomedical applications.

Distinguishing Protein Corona from Nanoparticle Aggregate Formation in Complex Biological Media Using X-ray Photon Correlation Spectroscopy

In biological systems, nanoparticles interact with biomolecules, which may undergo protein corona formation that can result in noncontrolled aggregation. Therefore, comprehending the behavior and evolution of nanoparticles in the presence of biological fluids is paramount in nanomedicine. However, traditional lab-based colloid methods characterize diluted suspensions in low-complexity media, which hinders in-depth studies in complex biological environments. Here, we apply X-ray photon correlation spectroscopy (XPCS) to investigate silica nanoparticles (SiO2) in various environments, ranging from low to high complex biological media. Interestingly, SiO2 revealed Brownian motion behavior, irrespective of the complexity of the chosen media. Moreover, the SiO2 surface and media composition were tailored to underline the differences between a corona-free system from protein corona and aggregates formation. Our results highlighted XPCS potential for real-time nanoparticle analysis in biological media, surpassing the limitations of conventional techniques and offering deeper insights into colloidal behavior in complex environments.

Advancements in tantalum based nanoparticles for integrated imaging and photothermal therapy in cancer management

Tantalum-based nanoparticles (TaNPs) have emerged as promising tools in cancer management, owing to their unique properties that facilitate innovative imaging and photothermal therapy applications. This review provides a comprehensive overview of recent advancements in TaNPs, emphasizing their potential in oncology. Key features include excellent biocompatibility, efficient photothermal conversion, and the ability to integrate multifunctional capabilities, such as targeted drug delivery and enhanced imaging. Despite these advantages, challenges remain in establishing long-term biocompatibility, optimizing therapeutic efficacy through surface modifications, and advancing imaging techniques for real-time monitoring. Strategic approaches to address these challenges include surface modifications like PEGylation to improve biocompatibility, precise control over size and shape for effective photothermal therapy, and the development of biodegradable TaNPs for safe elimination from the body. Furthermore, integrating advanced imaging modalities-such as photoacoustic imaging, magnetic resonance imaging (MRI), and computed tomography (CT)-enable real-time tracking of TaNPs in vivo, which is crucial for clinical applications. Personalized medicine strategies that leverage biomarkers and genetic profiling also hold promise for tailoring TaNP-based therapies to individual patient profiles, thereby enhancing treatment efficacy and minimizing side effects. In conclusion, TaNPs represent a significant advancement in nanomedicine, poised to transform cancer treatment paradigms while expanding into various biomedical applications.

Intestinal distribution of anionic, cationic, and neutral polymer-stabilized nanocarriers measured with a lanthanide (europium) tracer assay

Nanocarriers, more commonly called nanoparticles (NPs), have found increasing use as delivery vehicles which increase the oral bioavailability of poorly water-soluble and peptide therapeutics. Therapeutic bioavailability is commonly assessed by measuring plasma concentrations that reflect the absorption kinetics. This bioavailability is a convolution of the gastrointestinal distribution of the NP vehicle, the release rate of the encapsulated therapeutic cargo, and the absorption-metabolism-distribution kinetics of the released therapeutic. The spatiotemporal distribution of the NP vehicle in the gastrointestinal tract is not well studied and is a buried parameter in PK studies used to measure the effectiveness of an NP formulation. This work is a study of the intestinal distribution and fate of orally dosed NPs in male CD-1 mice over 24 h. NPs have identical hydrophobic cores - composed of poly(styrene) homopolymer, a naphthalocyanine dye, and oleate-coated europium oxide colloids - with one of four different surface stabilizers: neutral poly(styrene)-block-poly(ethylene glycol) (PS-b-PEG), moderately negative hydroxypropyl methylcellulose acetate succinate (HPMCAS), highly negative poly(styrene)-block-poly(acrylic acid) (PS-b-PAA), and highly cationic adsorbed chitosan HCl on PS-b-PAA stabilized NPs. NP hydrodynamic diameters are all below 200 nm, with some variation attributable to the molecular properties of the stabilizing polymer. The encapsulated hydrophobic europium oxide colloids do not release soluble europium ions, enabling the use of highly sensitive inductively coupled plasma mass spectrometry (ICP-MS) to detect NP concentrations in digested biological tissues. Highly anionically-charged PAA and cationically-charged chitosan stabilized NPs showed statistically significant increased retention compared to the neutral PEG-stabilized NPs at p < 0.05 significance and (1-β) > 0.95 power. HPMCAS-stabilized NPs showed statistically insignificant greater retention than PEG-stabilized NPs, and all NP formulations showed clearance from the intestines within 24 h. Different surface charges preferentially reside in different segments of the intestines, where cationic chitosan-stabilized NPs showed increased retention in the small intestines (ileum) and anionic PAA-stabilized NPs in the large intestines (caecum and colon). Modifying the surface charge of a NP can be used to modulate mucoadhesion, total retention, and intestinal segment specific retention, which enables the rational design of delivery vehicles that maximize residence times in appropriate locations.

Deciphering nanoparticle protein coronas by capillary isoelectric focusing-mass spectrometry-based top-down proteomics

The nanoparticle (NP) protein corona significantly influences the outcome of nanomedicine. We present the first example of top-down proteomics (TDP) measurement of the protein corona using capillary isoelectric focusing-mass spectrometry, identifying seventy proteoforms of 16 cancer-related genes. This technique has the potential to revolutionize our understanding of the protein corona and advance nanomedicine.

Mass Spectrometry-Based Top-Down Proteomics in Nanomedicine: Proteoform-Specific Measurement of Protein Corona

Conventional mass spectrometry (MS)-based bottom-up proteomics (BUP) analysis of the protein corona [i.e., an evolving layer of biomolecules, mostly proteins, formed on the surface of nanoparticles (NPs) during their interactions with biomolecular fluids] enabled the nanomedicine community to partly identify the biological identity of NPs. Such an approach, however, fails to pinpoint the specific proteoforms─distinct molecular variants of proteins in the protein corona. The proteoform-level information could potentially advance the prediction of the biological fate and pharmacokinetics of nanomedicines. Recognizing this limitation, this study pioneers a robust and reproducible MS-based top-down proteomics (TDP) technique for characterizing proteoforms in the protein corona. Our TDP approach has successfully identified about 900 proteoforms in the protein corona of polystyrene NPs, ranging from 2 to 70 kDa, revealing proteoforms of 48 protein biomarkers with combinations of post-translational modifications, signal peptide cleavages, and/or truncations─details that BUP could not fully discern. This advancement in MS-based TDP offers a more advanced approach to characterize NP protein coronas, deepening our understanding of NPs' biological identities. We, therefore, propose using both TDP and BUP strategies to obtain more comprehensive information about the protein corona, which, in turn, can further enhance the diagnostic and therapeutic efficacy of nanomedicine technologies.

The biomolecule corona mediates pulmonary delivery of nanomedicine

Pulmonary delivery of therapeutics (e.g., biologics, antibiotics, and chemotherapies) encapsulated in nanoparticles is desirable for the ability to provide a localised treatment, bypassing the harsh gastrointestinal environment. However, limited understanding of the biological fate of nanoparticles upon administration to the lungs hinders translation of pre-clinical investigations into viable therapies. A key knowledge gap is the impact of the pulmonary biomolecular corona on the functionality of nanoparticles. In this review, opportunities and challenges associated with pulmonary nanoparticle delivery are elucidated, highlighting the impact of the pulmonary biomolecular corona on immune recognition and nanoparticle internalisation in target cells. Recent investigations detailing the influence of proteins, lipids and mucin derived from pulmonary surfactants on nanoparticle behaviour are detailed. In addition, latest approaches in modulating plasma protein corona upon systemic delivery for biodistribution to the lungs are also discussed. Key examples of reengineering nanoparticle structure to mediate formation of biomolecule corona are provided. This review aims to provide a comprehensive understanding on biomolecular corona of nanoparticles for pulmonary delivery, while accentuating their significance for successful translation of newly investigated therapeutics.

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.

Polyester nanoparticles delivering chemotherapeutics: Learning from the past and looking to the future to enhance their clinical impact in tumor therapy

Polymeric nanoparticles (NPs), specifically those comprised of biodegradable and biocompatible polyesters, have been heralded as a game-changing drug delivery platform. In fact, poly(α-hydroxy acids) such as polylactide (PLA), poly(lactide-co-glycolide) (PLGA), and poly(ε-caprolactone) (PCL) have been heavily researched in the past three decades as the material basis of polymeric NPs for drug delivery applications. As materials, these polymers have found success in resorbable sutures, biodegradable implants, and even monolithic, biodegradable platforms for sustained release of therapeutics (e.g., proteins and small molecules) and diagnostics. Few fields have gained more attention in drug delivery through polymeric NPs than cancer therapy. However, the clinical translational of polymeric nanomedicines for treating solid tumors has not been congruent with the fervor or funding in this particular field of research. Here, we attempt to provide a comprehensive snapshot of polyester NPs in the context of chemotherapeutic delivery. This includes a preliminary exploration of the polymeric nanomedicine in the cancer research space. We examine the various processes for producing polyester NPs, including methods for surface-functionalization, and related challenges. After a detailed overview of the multiple factors involved with the delivery of NPs to solid tumors, the crosstalk between particle design and interactions with biological systems is discussed. Finally, we report state-of-the-art approaches toward effective delivery of NPs to tumors, aiming at identifying new research areas and re-evaluating the reasons why some research avenues have underdelivered. We hope our effort will contribute to a better understanding of the gap to fill and delineate the future research work needed to bring polyester-based NPs closer to clinical application. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Aptamer-free upconversion nanoparticle/silk biosensor system for low-cost and highly sensitive detection of antibiotic residues

The detection of antibiotics is crucial for safeguarding the environment, ensuring food safety, and promoting human health. However, developing a rapid, convenient, low-cost, and sensitive method for antibiotic detection presents significant challenges. Herein, an aptamer-free biosensor was successfully constructed using upconversion nanoparticles (UCNPs) coated with silk fibroin (SF), based on Förster resonance energy transfer (FRET) and the charge-transfer effect, for detecting roxithromycin (RXM). A synergistic FRET efficiency was achieved by utilizing alizarin red and RXM complexes as energy acceptors, with UCNP as the energy donor, and immobilizing an ultrathin SF protein corona within 10 nm. The biosensor detects RXM in deionized water with high sensitivity primarily through monolayer adsorption, with a detection range of 1.0 nM-141.6 nM and a detection limit as low as 0.68 nM. The performance of this biosensor was compared with the ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS) method for detecting antibiotics in river water separately and a strong correlation between the two methods was observed. The biosensor exhibited long-term stability in aqueous solutions (up to 60 d) with no attenuation of fluorescence intensity. Furthermore, the biosensor's applicability extended to the highly sensitive detection of other antibiotics, such as azithromycin. This study introduces a low-cost, eco-friendly, and highly sensitive method for antibiotic detection, with broad potential for future applications in environmental, healthcare, and food-related fields.

Protein Corona-Directed Cellular Recognition and Uptake of Polyethylene Nanoplastics by Macrophages

The widespread use of plastic products in daily life has raised concerns about the health hazards associated with nanoplastics (NPs). When exposed, NPs are likely to infiltrate the bloodstream, interact with plasma proteins, and trigger macrophage recognition and clearance. In this study, we focused on establishing a correlation between the unique protein coronal signatures of high-density (HDPE) and low-density (LDPE) polyethylene (PE) NPs with their ultimate impact on macrophage recognition and cytotoxicity. We observed that low-density and high-density lipoprotein receptors (LDLR and SR-B1), facilitated by apolipoproteins, played an essential role in PE-NP recognition. Consequently, PE-NPs activated the caspase-3/GSDME pathway and ultimately led to pyroptosis. Advanced imaging techniques, including label-free scattered light confocal imaging and cryo-soft X-ray transmission microscopy with 3D-tomographic reconstruction (nano-CT), provided powerful insights into visualizing NPs-cell interactions. These findings underscore the potential risks of NPs to macrophages and introduce analytical methods for studying the behavior of NPs in biological systems.

Boron Neutron Capture Therapy Enhanced by Boronate Ester Polymer Micelles: Synthesis, Stability, and Tumor Inhibition Studies

Boron neutron capture therapy (BNCT) targets invasive, radioresistant cancers but requires a selective and high B-10 loading boron drug. This manuscript investigates boron-rich poly(ethylene glycol)-block-(poly(4-vinylphenyl boronate ester)) polymer micelles synthesized via atom transfer radical polymerization for their potential application in BNCT. Transmission electron microscopy (TEM) revealed spherical micelles with a uniform size of 43 ± 10 nm, ideal for drug delivery. Additionally, probe sonication proved effective in maintaining the micelles' size and morphology postlyophilization and reconstitution. In vitro studies with B16-F10 melanoma cells demonstrated a 38-fold increase in boron accumulation compared to the borophenylalanine drug for BNCT. In vivo studies in a B16-F10 tumor-bearing mouse model confirmed enhanced tumor selectivity and accumulation, with a tumor-to-blood (T/B) ratio of 2.5, surpassing BPA's T/B ratio of 1.8. As a result, mice treated with these micelles experienced a significant delay in tumor growth, highlighting their potential for BNCT and warranting further research.

Peptide-Hitchhiking for the Development of Nanosystems in Glioblastoma

Glioblastoma (GBM) remains the epitome of aggressiveness and lethality in the spectrum of brain tumors, primarily due to the blood-brain barrier (BBB) that hinders effective treatment delivery, tumor heterogeneity, and the presence of treatment-resistant stem cells that contribute to tumor recurrence. Nanoparticles (NPs) have been used to overcome these obstacles by attaching targeting ligands to enhance therapeutic efficacy. Among these ligands, peptides stand out due to their ease of synthesis and high selectivity. This article aims to review single and multiligand strategies critically. In addition, it highlights other strategies that integrate the effects of external stimuli, biomimetic approaches, and chemical approaches as nanocatalytic medicine, revealing their significant potential in treating GBM with peptide-functionalized NPs. Alternative routes of parenteral administration, specifically nose-to-brain delivery and local treatment within the resected tumor cavity, are also discussed. Finally, an overview of the significant obstacles and potential strategies to overcome them are discussed to provide a perspective on this promising field of GBM therapy.

Advances in chitosan-based blends as potential drug delivery systems: A review

During the last decades, the ever-increasing incidence of diseases has led to high rates of mortality throughout the world. On the other hand, the inability and deficiencies of conventional approaches (such as chemotherapy) in the suppression of diseases remain challenging issues. As a result, there is a fundamental requirement to develop novel, biocompatible, bioavailable, and practical nanomaterials to prevent the incidence and mortality of diseases. Chitosan (CS) derivatives and their blends are outstandingly employed as promising drug delivery systems for disease therapy. These biopolymers are indicated more efficient performance against diseases compared with conventional modalities. The CS blends possess improved physicochemical properties, ease of preparation, high affordability, etc. characteristics compared with other biopolymers and even pure CS which result in efficient thermal, mechanical, biochemical, and biomedical features. Also, these blends can be administrated through different routes without a long-term treatment period. Due to the mentioned properties, numerous formulations of CS blends are developed for pharmaceutical sciences to treat diseases. This review article highlights the progressions in the development of CS-based blends as potential drug delivery systems against diseases.

Polymer-drug and polymer-protein conjugated nanocarriers: Design, drug delivery, imaging, therapy, and clinical applications

Polymer-drug conjugates and polymer-protein conjugates have been pivotal in the realm of drug delivery systems for over half a century. These polymeric drugs are characterized by the conjugation of therapeutic molecules or functional moieties to polymers, enabling a range of benefits including extended circulation times, targeted delivery, controlled release, and decreased immunogenicity. This review delves into recent advancements and challenges in the clinical translations and preclinical studies of polymer-drug conjugates and polymer-protein conjugates. The design principles and functionalization strategies crucial for the development of these polymeric drugs were explored followed by the review of structural properties and characteristics of various polymer carriers. This review also identifies significant obstacles in the clinical translation of polymer-drug conjugates and provides insights into the directions for their future development. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Supramolecular Heterodimer Peptides Assembly for Nanoparticles Functionalization

Nanoparticle (NP) surface functionalization with proteins, including monoclonal antibodies (mAbs), mAb fragments, and various peptides, has emerged as a promising strategy to enhance tumor targeting specificity and immune cell interaction. However, these methods often rely on complex chemistry and suffer from batch-dependent outcomes, primarily due to limited control over the protein orientation and quantity on NP surfaces. To address these challenges, a novel approach based on the supramolecular assembly of two peptides is presented to create a heterotetramer displaying VHHs on NP surfaces. This approach effectively targets both tumor-associated antigens (TAAs) and immune cell-associated antigens. In vitro experiments showcase its versatility, as various NP types are biofunctionalized, including liposomes, PLGA NPs, and ultrasmall silica-based NPs, and the VHHs targeting of known TAAs (HER2 for breast cancer, CD38 for multiple myeloma), and an immune cell antigen (NKG2D for natural killer (NK) cells) is evaluated. In in vivo studies using a HER2+ breast cancer mouse model, the approach demonstrates enhanced tumor uptake, retention, and penetration compared to the behavior of nontargeted analogs, affirming its potential for diverse applications.