Polyglycerol Grafting Shields Nanoparticles from Protein Corona Formation to Avoid Macrophage Uptake

Effect of Nanoparticle Curvature on Its Interaction with Serum Proteins

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

Substituting Poly(ethylene glycol) Lipids with Poly(2-ethyl-2-oxazoline) Lipids Improves Lipid Nanoparticle Repeat Dosing

Poly(ethylene glycol) (PEG)-lipids are used in Food-and-Drug-Administration-approved lipid nanoparticle (LNP)-RNA drugs, which are safe and effective. However, it is reported that PEG-lipids may also contribute to accelerated blood clearance and rare cases of hypersensitivity; this highlights the utility of exploring PEG-lipid alternatives. Here, it is shown that LNPs containing poly(2-ethyl-2-oxazoline) (PEOZ)-lipids can deliver messenger RNA (mRNA) to multiple cell types in mice inside and outside the liver. In addition, it is reported that LNPs formulated with PEOZ-lipids show reduced clearance from the bloodstream and lower levels of antistealth lipid immunoglobulin Ms than LNPs formulated with PEG-lipids. These data justify further exploration of PEOZ-lipids as alternatives to PEG-lipids in LNP-RNA formulations.

Stealth and Biocompatible Gold Nanoparticles through Surface Coating with a Zwitterionic Derivative of Glutathione

Gold nanoparticles (AuNPs) hold promise in biomedicine, but challenges like aggregation, protein corona formation, and insufficient biocompatibility must be thoroughly addressed before advancing their clinical applications. Designing AuNPs with specific protein corona compositions is challenging, and strategies for corona elimination, such as coating with polyethylene glycol (PEG), have limitations. In this study, we introduce a commercially available zwitterionic derivative of glutathione, glutathione monoethyl ester (GSHzwt), for the surface coating of colloidal AuNPs. Particles coated with GSHzwt were investigated alongside four other AuNPs coated with various ligands, including citrate ions, tiopronin, glutathione, cysteine, and PEG. We then undertook a head-to-head comparison of these AuNPs to assess their behavior in biological fluid. GSHzwt-coated AuNPs exhibited exceptional resistance to aggregation and protein adsorption. The particles could also be readily functionalized with biotin and interact with streptavidin receptors in human plasma. Additionally, they exhibited significant blood compatibility and noncytotoxicity. In conclusion, GSHzwt provides a practical and easy method for the surface passivation of AuNPs, creating "stealth" particles for potential clinical applications.

Size, polyglycerol grafting, and net surface charge of iron oxide nanoparticles determine their interaction and toxicity in Caenorhabditis elegans

The widespread application of engineered nanoparticles (NPs) in environmental remediation has raised public concerns about their toxicity to aquatic organisms. Although appropriate surface modification can mitigate the ecotoxicity of NPs, the lack of polymer coating to inhibit toxicity completely and the insufficient knowledge about charge effect hinder the development of safe nanomaterials. Herein, we explored the potential of polyglycerol (PG) functionalization in alleviating the environmental risks of NPs. Iron oxide NPs (ION) of 20, 100, and 200 nm sizes (IONS, IONM and IONL, respectively) were grafted with PG to afford ION-PG. We examined the interaction of ION and ION-PG with Caenorhabditis elegans (C. elegans) and found that PG suppressed non-specific interaction of ION with C. elegans to reduce their accumulation and to inhibit their translocation. Particularly, IONS-PG was completely excluded from worms of all developmental stages. By covalently introducing sulfate, carboxyl and amino groups onto IONS-PG, we further demonstrated that positively charged IONS-PG-NH3+ induced high intestinal accumulation, cuticle adhesion and distal translocation, whereas the negatively charged IONS-PG-OSO3- and IONS-PG-COO- were excreted out. Consequently, no apparent deleterious effects on brood size and life span were observed in worms treated by IONS-PG and IONS-PG bearing negatively charged groups. This study presents new surface functionalization approaches for developing ecofriendly nanomaterials.

Applications and advancements of polysaccharide-based nanostructures for enhanced drug delivery

Growing demand for highly effective, site-specific delivery of pharmaceuticals and nutraceuticals using nano-sized carriers has prompted increased scrutiny of carrier biocompatibility and biodegradability. To address these concerns, biodegradable natural polymers have emerged as a transformative domain, offering non-toxic, precisely targetable carriers capable of finely modulating cargo pharmacokinetics while generating innocuous decomposition by-products. This comprehensive review illuminates the emergence of polysaccharide-based nanoparticulate drug delivery systems. These systems establish an interactive interface between drug and targeted organs, guided by strategic modifications to polysaccharide backbones, which facilitate the creation of morphologically, constitutionally, and characteristically vibrant nanostructures through various fabrication routes, underpinning their pivotal role in biomedical applications. Advancements crucial to enhancing polysaccharide-based drug delivery, such as surface modifications and bioinspired modifications for enhanced targeting, and stimuli-responsive release, strategies to overcome biological barriers, enhance tumor penetration, and optimize therapeutic outcomes are highlighted. This review also examines some potent challenges, and the contemporary way out of them, and discusses future perspectives in the field.

Manipulation of Macrophage Uptake by Controlling the Aspect Ratio of Graft Copolymer Micelles

Nanostructures of drug carriers play a crucial role in nanomedicine due to their ability to influence drug delivery. There is yet no clear consensus regarding the optimal size and shape (e.g., aspect ratio) of nanoparticles for minimizing macrophage uptake, given the difficulties in controlling the shape and size of nanoparticles while maintaining identical surface properties. Here, we employed graft copolymer self-assembly to prepare polymer micelles with aspect ratios ranging from 1.0 (spherical) to 10.8 (cylindrical) and closely matched interfacial properties. Notably, our findings emphasize that cylindrical micelles with an aspect ratio of 2.4 are the least susceptible to macrophage uptake compared with both their longer counterparts and spherical micelles. This reduced uptake of the short cylindrical micelles results in a 3.3-fold increase in blood circulation time compared with their spherical counterparts. Controlling the aspect ratio of nanoparticles is crucial for improving drug delivery efficacy through better nanoparticle design.

Quantification of Poly(ethylene glycol) Crowding on Nanodiamonds toward Quantum Biosensor for Improved Prevention Effects on Protein Adsorption and Lung Accumulation

Nanometer-sized diamonds (NDs) containing nitrogen vacancy centers have garnered significant attention as potential quantum sensors for reading various types of physicochemical information in vitro and in vivo. However, NDs intrinsically aggregate when placed in biological environments, hampering their sensing capacities. To address this issue, the grafting of hydrophilic polymers onto the surface of NDs has been demonstrated considering their excellent ability to prevent protein adsorption. To this end, crowding of the grafted chains plays a crucial role because it is directly associated with the antiadsorption effect of proteins; however, its quantitative evaluation has not been reported previously. In this study, we graft poly(ethylene glycol) (PEG) with various molecular weights onto NDs, determine their crowding using a gas adsorption technique, and disclose the cross-correlation between the pH in the grafting reaction, crowding density, molecular weight, and the prevention effect on protein adsorption. PEG-grafted NDs exhibit a pronounced effect on the prevention of lung accumulation after intravenous injection in mice. PEG crowding was compared to that calculated by using a diameter determined by dynamic light scattering (DLS) assuming a sphere.

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.

Engineering mesoporous bioactive glasses for emerging stimuli-responsive drug delivery and theranostic applications

Mesoporous bioactive glasses (MBGs), which belong to the category of modern porous nanomaterials, have garnered significant attention due to their impressive biological activities, appealing physicochemical properties, and desirable morphological features. They hold immense potential for utilization in diverse fields, including adsorption, separation, catalysis, bioengineering, and medicine. Despite possessing interior porous structures, excellent morphological characteristics, and superior biocompatibility, primitive MBGs face challenges related to weak encapsulation efficiency, drug loading, and mechanical strength when applied in biomedical fields. It is important to note that the advantageous attributes of MBGs can be effectively preserved by incorporating supramolecular assemblies, miscellaneous metal species, and their conjugates into the material surfaces or intrinsic mesoporous networks. The innovative advancements in these modified colloidal inorganic nanocarriers inspire researchers to explore novel applications, such as stimuli-responsive drug delivery, with exceptional in-vivo performances. In view of the above, we outline the fabrication process of calcium-silicon-phosphorus based MBGs, followed by discussions on their significant progress in various engineered strategies involving surface functionalization, nanostructures, and network modification. Furthermore, we emphasize the recent advancements in the textural and physicochemical properties of MBGs, along with their theranostic potentials in multiple cancerous and non-cancerous diseases. Lastly, we recapitulate compelling viewpoints, with specific considerations given from bench to bedside.

Protein-based nanoparticles for therapeutic nucleic acid delivery

To realize the full potential of emerging nucleic acid therapies, there is a need for effective delivery agents to transport cargo to cells of interest. Protein materials exhibit several unique properties, including biodegradability, biocompatibility, ease of functionalization via recombinant and chemical modifications, among other features, which establish a promising basis for therapeutic nucleic acid delivery systems. In this review, we highlight progress made in the use of non-viral protein-based nanoparticles for nucleic acid delivery in vitro and in vivo, while elaborating on key physicochemical properties that have enabled the use of these materials for nanoparticle formulation and drug delivery. To conclude, we comment on the prospects and unresolved challenges associated with the translation of protein-based nucleic acid delivery systems for therapeutic applications.

Cellular uptake and cytotoxicity of PEGylated MXene nanomaterials mediated by protein corona

A stringent analysis of the biocompatibility of MXene is a necessary condition for assessing the biological risk of MXene. Owing to high surface free energy, MXene is capable of adsorbing a large amount of blood proteins to form MXene-protein corona complexes, however, a comprehensive understanding of the relationship between MXene and cellular physiological systems remains limited. Therefore, we investigated the cellular uptake and cytotoxicity effect of MXene Ti3C2Tx and PEGylation Ti3C2Tx mediated by human serum protein corona in THP-1 cells. It was found that PEGylation can alter the interaction between Ti3C2Tx and serum proteins, inducing a significant transformation in the fingerprint of the protein corona. Following protein corona formation, both Ti3C2Tx and PEGylated Ti3C2Tx predominantly accumulated at lysosomal sites within THP-1 cells. Further analysis revealed that clathrin-mediated endocytosis was the primary mechanism of Ti3C2Tx internalization by THP-1 cells. There was no significant effect on cell viability. However, we found that Ti3C2Tx plays a dual role as both a stimulus and scavenger of ROS within THP-1 cells, influenced by its PEGylation and the formation of a protein corona. This study provides important insights for biocompatibility evaluation and rational design of nanoproducts based on Ti3C2Tx in the future.

Nano-bio interactions in mRNA nanomedicine: Challenges and opportunities for targeted mRNA delivery

Upon entering the biological milieu, nanomedicines swiftly interact with the surrounding tissue fluid, subsequently being enveloped by a dynamic interplay of biomacromolecules, such as carbohydrates, nucleic acids, and cellular metabolites, but with predominant serum proteins within the biological corona. A notable consequence of the protein corona phenomenon is the unintentional loss of targeting ligands initially designed to direct nanomedicines toward particular cells or organs within the in vivo environment. mRNA nanomedicine displays high demand for specific cell and tissue-targeted delivery to effectively transport mRNA molecules into target cells, where they can exert their therapeutic effects with utmost efficacy. In this review, focusing on the delivery systems and tissue-specific applications, we aim to update the nanomedicine population with the prevailing and still enigmatic paradigm of nano-bio interactions, a formidable hurdle in the pursuit of targeted mRNA delivery. We also elucidate the current impediments faced in mRNA therapeutics and, by contemplating prospective avenues-either to modulate the corona or to adopt an 'ally from adversary' approach-aim to chart a course for advancing mRNA nanomedicine.

Differential cellular responses to FDA-approved nanomedicines: an exploration of albumin-based nanocarriers and liposomes in protein corona formation

Albumin nanoparticles (NPs) and PEGylated liposomes have garnered tremendous interest as therapeutic drug carriers due to their unique physicochemical properties. These unique properties also have significant effects on the composition and structure of the protein corona formed around these NPs in a biological environment. Herein, protein corona formation on albumin NPs and liposomes was simultaneously evaluated through in vitro and simulation studies. The sizes of both types of NPs increased with more negatively charged interfaces upon being introduced into fetal bovine serum. Gel electrophoresis and label-free quantitative proteomics were performed to identify proteins recruited to the hard corona, and fewer proteins were found in albumin NPs than in liposomes, which is in accordance with isothermal titration calorimetry. The cellular uptake efficiency of the two NPs significantly differed in different serum concentrations, which was further scrutinized by loading an anticancer compound into albumin NPs. The presence of the hard protein corona increased the cellular uptake of albumin NPs in comparison with liposomes. In our simulation study, a specific receptor present in the membrane was greatly attracted to the albumin-apolipoprotein E complex. Overall, this study not only evaluated protein corona formation on albumin NPs, but also made promising advancements toward albumin- and liposome-based therapeutic systems.

Rational Design, Multistep Synthesis and in Vitro Evaluation of Poly(glycerol) Functionalized Nanodiamond Conjugated with Boron-10 Cluster and Active Targeting Moiety for Boron Neutron Capture Therapy

Boron neutron capture therapy (BNCT), advanced cancer treatment utilizing nuclear fission of 10 B atom in cancer cells, is attracting increasing attention. As 10 B delivery agent, sodium borocaptate (10 BSH, 10 B12 H11 SH ⋅ 2Na), has been used in clinical studies along with L-boronophenylalanine. Recently, this boron cluster has been conjugated with lipids, polymers or nanoparticles to increase selectivity to and retentivity in tumor. In this work, anticancer nanoformulations for BNCT are designed, consisting of poly(glycerol) functionalized detonation nanodiamonds (DND-PG) as a hydrophilic nanocarrier, the boron cluster moiety (10 B12 H11 2- ) as a dense boron-10 source, and phenylboronic acid or RGD peptide as an active targeting moiety. Some hydroxy groups in PG were oxidized to carboxy groups (DND-PG-COOH) to conjugate the active targeting moiety. Some hydroxy groups in DND-PG-COOH were then transformed to azide to conjugate 10 B12 H11 2- through click chemistry. The nanodrugs were evaluated in vitro using B16 murine melanoma cells in terms of cell viability, BNCT efficacy and cellular uptake. As a result, the 10 B12 H11 2- moiety is found to facilitate cellular uptake probably due to its negative charge. Upon thermal neutron irradiation, the nanodrugs with 10 B12 H11 2- moiety exhibited good anticancer efficacies with slight differences with and without targeting moiety.

Bright and Stable Nanomaterials for Imaging and Sensing

This review covers strategies to prepare high-performance emissive polymer nanomaterials, combining very high brightness and photostability, to respond to the drive for better imaging quality and lower detection limits in fluorescence imaging and sensing applications. The more common approaches to obtaining high-brightness nanomaterials consist of designing polymer nanomaterials carrying a large number of fluorescent dyes, either by attaching the dyes to individual polymer chains or by encapsulating the dyes in nanoparticles. In both cases, the dyes can be covalently linked to the polymer during polymerization (by using monomers functionalized with fluorescent groups), or they can be incorporated post-synthesis, using polymers with reactive groups, or encapsulating the unmodified dyes. Silica nanoparticles in particular, obtained by the condensation polymerization of silicon alcoxides, provide highly crosslinked environments that protect the dyes from photodegradation and offer excellent chemical modification flexibility. An alternative and less explored strategy is to increase the brightness of each individual dye. This can be achieved by using nanostructures that couple dyes to plasmonic nanoparticles so that the plasmon resonance can act as an electromagnetic field concentrator to increase the dye excitation efficiency and/or interact with the dye to increase its emission quantum yield.

Tumor Eradication by Boron Neutron Capture Therapy with 10 B-enriched Hexagonal Boron Nitride Nanoparticles Grafted with Poly(Glycerol)

Boron neutron capture therapy (BNCT) has emerged as a treatment modality with high precision and efficacy of intractable tumors. At the core of effective tumor BNCT are 10 B carriers with facile preparation as well as advantageous pharmacokinetic and therapeutic profiles. Herein, the design and preparation of sub-10 nm 10 B-enriched hexagonal boron nitride nanoparticles grafted with poly(glycerol) (h-10 BN-PG), and their application to cancer treatment by BNCT are reported. By virtue of their small particle size and outstanding stealth property, h-10 BN-PG nanoparticles accumulate efficiently in murine CT26 colon tumors with a high intratumor 10 B concentration of 8.8%ID g-1 or 102.1 µg g-1 at 12 h post-injection. Moreover, h-10 BN-PG nanoparticles penetrate into the inside of the tumor parenchyma and then are taken up by the tumor cells. BNCT comprising a single bolus injection of h-10 BN-PG nanoparticles and subsequent one-time neutron irradiation results in significant shrinkage of subcutaneous CT26 tumors. h-10 BN-PG-mediated BNCT not only causes direct DNA damage to the tumor cells, but also triggers pronounced inflammatory immune response in the tumor tissues, which contributes to long-lasting tumor suppression after the neutron irradiation. Thus, the h-10 BN-PG nanoparticles are promising BNCT agents to eradicate tumor through highly efficient 10 B accumulation.

Effective magnetic hyperthermia induced by mitochondria-targeted nanoparticles modified with triphenylphosphonium-containing phospholipid polymers

Magnetic hyperthermia (MHT) is a promising cancer treatment because tumor tissue can be specifically damaged by utilizing the heat generated by nano-heaters such as magnetite nanoparticles (MNPs) under an alternating magnetic field. MNPs are taken up by cancer cells, enabling intracellular MHT. Subcellular localization of MNPs can affect the efficiency of intracellular MHT. In this study, we attempted to improve the therapeutic efficacy of MHT by using mitochondria-targeting MNPs. Mitochondria-targeting MNPs were prepared by the modification of carboxyl phospholipid polymers containing triphenylphosphonium (TPP) moieties that accumulate in mitochondria. The mitochondrial localization of polymer-modified MNPs was supported by transmission electron microscopy observations of murine colon cancer CT26 cells treated with polymer-modified MNPs. In vitro and in vivo MHT using polymer-modified MNPs revealed that the therapeutic effects were enhanced by introducing TPP. Our results indicate the validity of mitochondria targeting in enhancing the therapeutic outcome of MHT. These findings will pave the way for developing a new strategy for the surface design of MNPs and therapeutic strategies for MHT.

Nanotubes from bacteriophage tail sheath proteins: internalisation by cancer cells and macrophages

Bionanoparticles comprised of naturally occurring monomers are gaining interest in the development of novel drug transportation systems. Here we report on the stabilisation, cellular uptake, and macrophage clearance of nanotubes formed from the self-assembling gp053 tail sheath protein of the vB_EcoM_FV3 bacteriophage. To evaluate the potential of the bacteriophage protein-based nanotubes as therapeutic nanocarriers, we investigated their internalisation into colorectal cancer cell lines and professional macrophages that may hinder therapeutic applications by clearing nanotube carriers. We fused the bacteriophage protein with a SNAP-tag self-labelling enzyme and demonstrated that its activity is retained in assembled nanotubes, indicating that such carriers can be applied to deliver therapeutic biomolecules. Under physiological conditions, the stabilisation of the nanotubes by PEGylation was required to prevent aggregation and yield a stable solution with uniform nano-sized structures. Colorectal carcinoma cells from primary and metastatic tumours internalized SNAP-tag-carrying nanotubes with different efficiencies. The nanotubes entered HCT116 cells via dynamin-dependent and SW480 cells - via dynamin- and clathrin-dependent pathways and were accumulated in lysosomes. Meanwhile, peritoneal macrophages phagocytosed the nanotubes in a highly efficient manner through actin-dependent mechanisms. Macrophage clearance of nanotubes was enhanced by inflammatory activation but was dampened in macrophages isolated from aged animals. Altogether, our results demonstrate that gp053 nanotubes retained the cargo's enzymatic activity post-assembly and had the capacity to enter cancer cells. Furthermore, we emphasise the importance of evaluating the nanocarrier clearance by immune cells under conditions mimicking a cancerous environment.

Counteracting Immunosenescence-Which Therapeutic Strategies Are Promising?

Aging attenuates the overall responsiveness of the immune system to eradicate pathogens. The increased production of pro-inflammatory cytokines by innate immune cells under basal conditions, termed inflammaging, contributes to impaired innate immune responsiveness towards pathogen-mediated stimulation and limits antigen-presenting activity. Adaptive immune responses are attenuated as well due to lowered numbers of naïve lymphocytes and their impaired responsiveness towards antigen-specific stimulation. Additionally, the numbers of immunoregulatory cell types, comprising regulatory T cells and myeloid-derived suppressor cells, that inhibit the activity of innate and adaptive immune cells are elevated. This review aims to summarize our knowledge on the cellular and molecular causes of immunosenescence while also taking into account senescence effects that constitute immune evasion mechanisms in the case of chronic viral infections and cancer. For tumor therapy numerous nanoformulated drugs have been developed to overcome poor solubility of compounds and to enable cell-directed delivery in order to restore immune functions, e.g., by addressing dysregulated signaling pathways. Further, nanovaccines which efficiently address antigen-presenting cells to mount sustained anti-tumor immune responses have been clinically evaluated. Further, senolytics that selectively deplete senescent cells are being tested in a number of clinical trials. Here we discuss the potential use of such drugs to improve anti-aging therapy.

Application of Nano-Delivery Systems in Lymph Nodes for Tumor Immunotherapy

Immunotherapy has become a promising research "hotspot" in cancer treatment. "Soldier" immune cells are not uniform throughout the body; they accumulate mostly in the immune organs such as the spleen and lymph nodes (LNs), etc. The unique structure of LNs provides the microenvironment suitable for the survival, activation, and proliferation of multiple types of immune cells. LNs play an important role in both the initiation of adaptive immunity and the generation of durable anti-tumor responses. Antigens taken up by antigen-presenting cells in peripheral tissues need to migrate with lymphatic fluid to LNs to activate the lymphocytes therein. Meanwhile, the accumulation and retaining of many immune functional compounds in LNs enhance their efficacy significantly. Therefore, LNs have become a key target for tumor immunotherapy. Unfortunately, the nonspecific distribution of the immune drugs in vivo greatly limits the activation and proliferation of immune cells, which leads to unsatisfactory anti-tumor effects. The efficient nano-delivery system to LNs is an effective strategy to maximize the efficacy of immune drugs. Nano-delivery systems have shown beneficial in improving biodistribution and enhancing accumulation in lymphoid tissues, exhibiting powerful and promising prospects for achieving effective delivery to LNs. Herein, the physiological structure and the delivery barriers of LNs were summarized and the factors affecting LNs accumulation were discussed thoroughly. Moreover, developments in nano-delivery systems were reviewed and the transformation prospects of LNs targeting nanocarriers were summarized and discussed.

Multifunctional nanostructures: Intelligent design to overcome biological barriers

Over the past three decades, nanoscience has offered a unique solution for reducing the systemic toxicity of chemotherapy drugs and for increasing drug therapeutic efficiency. However, the poor accumulation and pharmacokinetics of nanoparticles are some of the key reasons for their slow translation into the clinic. The is intimately linked to the non-biological nature of nanoparticles and the aberrant features of solid cancer, which together significantly compromise nanoparticle delivery. New findings on the unique properties of tumors and their interactions with nanoparticles and the human body suggest that, contrary to what was long-believed, tumor features may be more mirage than miracle, as the enhanced permeability and retention based efficacy is estimated to be as low as 1%. In this review, we highlight the current barriers and available solutions to pave the way for approved nanoformulations. Furthermore, we aim to discuss the main solutions to solve inefficient drug delivery with the use of nanobioengineering of nanocarriers and the tumor environment. Finally, we will discuss the suggested strategies to overcome two or more biological barriers with one nanocarrier. The variety of design formats, applications and implications of each of these methods will also be evaluated.

Highly Dispersed 3C Silicon Carbide Nanoparticles with a Polydopamine/Polyglycerol Shell for Versatile Functionalization

Silicon carbide (SiC) nanoparticles containing lattice defects are attracting considerable attention as next-generation imaging probes and quantum sensors for visualizing and sensing life activities. However, SiC nanoparticles are not currently used in biomedical applications because of the lack of technology for controlling their physicochemical properties. Therefore, in this study, SiC nanoparticles are deaggregated, surface-coated, functionalized, and selectively labeled to biomolecules of interest. A thermal-oxidation chemical-etching method is developed for deaggregating and producing a high yield of dispersed metal-contaminant-free SiC nanoparticles. We further demonstrated a polydopamine coating with controllable thickness that can be used as a platform for decorating gold nanoparticles on the surface, enabling photothermal application. We also demonstrated a polyglycerol coating, which gives excellent dispersity to SiC nanoparticles. Furthermore, a single-pot method is developed to produce mono/multifunctional polyglycerol-modified SiC nanoparticles. Using this method, CD44 proteins on cell surfaces are selectively labeled through biotin-mediated immunostaining. The methods developed in this study are fundamental for applying SiC nanoparticles to biomedical applications and should considerably accelerate the development of various SiC nanoparticles to exploit their potential applications in bioimaging and biosensing.

Magnetic Iron Oxide Nanoparticles for Brain Imaging and Drug Delivery

Central nervous system (CNS) disorders affect as many as 1.5 billion people globally. The limited delivery of most imaging and therapeutic agents into the brain is a major challenge for treatment of CNS disorders. With the advent of nanotechnologies, controlled delivery of drugs with nanoparticles holds great promise in CNS disorders for overcoming the blood-brain barrier (BBB) and improving delivery efficacy. In recent years, magnetic iron oxide nanoparticles (MIONPs) have stood out as a promising theranostic nanoplatform for brain imaging and drug delivery as they possess unique physical properties and biodegradable characteristics. In this review, we summarize the recent advances in MIONP-based platforms as imaging and drug delivery agents for brain diseases. We firstly introduce the methods of synthesis and surface functionalization of MIONPs with emphasis on the inclusion of biocompatible polymers that allow for the addition of tailored physicochemical properties. We then discuss the recent advances in in vivo imaging and drug delivery applications using MIONPs. Finally, we present a perspective on the remaining challenges and possible future directions for MIONP-based brain delivery systems.

Surface design of nanocarriers: Key to more efficient oral drug delivery systems

As nanocarriers (NCs) can improve the solubility of drugs, prevent their degradation by gastrointestinal (GI) enzymes and promote their transport across the mucus gel layer and absorption membrane, the oral bioavailability of these drugs can be substantially enhanced. All these properties of NCs including self-emulsifying drug delivery systems (SEDDS), solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), liposomes, polymeric nanoparticles, inorganic nanoparticles and polymeric micelles depend mainly on their surface chemistry. In particular, interaction with food, digestive enzymes, bile salts and electrolytes, diffusion behaviour across the mucus gel layer and fate on the absorption membrane are determined by their surface. Bioinert surfaces limiting interactions with gastrointestinal fluid and content as well as with mucus, adhesive surfaces providing an intimate contact with the GI mucosa and absorption enhancing surfaces can be designed. Furthermore, charge converting surfaces shifting their zeta potential from negative to positive directly at the absorption membrane and surfaces providing a targeted drug release are advantageous. In addition to these passive surfaces, even active surfaces cleaving mucus glycoproteins on their way through the mucus gel layer can be created. Within this review, we provide an overview on these different surfaces and discuss their impact on the performance of NCs in the GI tract.

Poly(Glycerol)-Based Biomedical Nanodevices Constructed by Functional Programming on Inorganic Nanoparticles for Cancer Nanomedicine

Nanomedicine is promising to improve conventional cancer medicine by making diagnosis and therapy more accurate and more effective in a more personalized manner. A key of the cancer nanomedicine is construction of medical nanodevices by programming various requisite functions to nanoparticles (NPs). As compared to that of soft NPs, including organic micelles and polymers, fabrication of an inorganic NP based nanodevice is still challenging; the approved nanoformulations have been confined to the limited number of superparamagnetic iron oxide NPs (SPIONs). The major challenges lie in how to program the requisite functions to inorganic NPs. In spite the much denser and less hydrophilic properties of inorganic NPs, most of the following functions have to be programmed for their in vivo applications: (A) high dispersibility in a physiological environment, (B) high stealth efficiency to slip through the trap by liver and spleen, (C) high targeting efficiency to cancer tissue, (D) clear visualization of cancer for diagnosis, and (E) high anticancer activity for treatment.In our approach, poly(glycerol) (PG), containing a hydroxy group at every monomer unit, was found as a better alternative to poly(ethylene glycol) (PEG), the most commonly used hydrophilic polymer, giving (A) high dispersibility to inorganic NPs. Although most of the inorganic NPs are not dense in functional groups, the hyperbranched structure with many hydroxy groups in PG turns the less functional surface into highly functional one, imparting not only good hydrophilicity but also (B) high stealth efficiency as we reported recently. In addition, a number of hydroxy groups in PG afford the structural or functional extensibility to introduce the additional layer or function. This enables us to design and construct a three-layer architecture consisting of a core inorganic NP, a hydrophilic and stealthy PG layer, and a functional molecule layer, where their interfaces are connected firmly by covalent bonds. The three-layered nanodevice is very flexible in its design for the following reasons: The PG coating can be applied to a wide variety of inorganic NPs with various functions, and various functional moieties can be introduced on the PG layer as a functional molecule layer. Owing to the versatility of the three-layer model, the rest of the above functions (C)-(E) can be programed in the NP core and/or the outmost layer in nanodevices.In this Account, the author described first the methodology for precise construction and quantitative characterization of various biomedical nanodevices. This fundamental aspect of this research has been achieved by "applying organic chemistry to nanomaterials" which is the concept of our research. That is, the rich chemistry in synthesis and characterization of organic compounds has been applied to the nanodevice fabrication and characterization. Second, evaluation of the functions programmed in the nanodevices is described in terms of stealth and targeting efficiencies, cancer diagnosis and therapy, and biomedical sensing. This stage in our research made us more interdisciplinary from chemistry and nanoscience to biology and medicine. The following research spiral has been established in our group to strongly promote the improvement of our biomedical nanodevices; nanodevice design → precise construction → quantitative characterization → functional evaluation.

Protein corona: Friend or foe? Co-opting serum proteins for nanoparticle delivery

For systemically delivered nanoparticles to reach target tissues, they must first circulate long enough to reach the target and extravasate there. A challenge is that the particles end up engaging with serum proteins and undergo immune cell recognition and premature clearance. The serum protein binding, also known as protein corona formation, is difficult to prevent, even with artificial protection via "stealth" coating. Protein corona may be problematic as it can interfere with the interaction of targeting ligands with tissue-specific receptors and abrogate the so-called active targeting process, hence, the efficiency of drug delivery. However, recent studies show that serum protein binding to circulating nanoparticles may be actively exploited to enhance their downstream delivery. This review summarizes known issues of protein corona and traditional strategies to control the corona, such as avoiding or overriding its formation, as well as emerging efforts to enhance drug delivery to target organs via nanoparticles. It concludes with a discussion of prevailing challenges in exploiting protein corona for nanoparticle development.

Sticktight-inspired PEGylation for low-fouling coatings

Polyethylene glycol (PEG) has been widely used for modifying surfaces to reduce non-specific interactions with biomolecules, microorganisms, and cells. Herein, we report a sticktight-inspired PEGylation strategy to fabricate low-fouling coatings. The influence of PEG molecular architectures on the PEG density and biological adhesion were studied. Notably, an increase in the number of arms resulted in improved surface PEGylation and an improved antifouling ability against the adhesion of proteins, mammalian cells and bacteria. The molecular architecture-dependent PEGylation strategy is an attractive approach for developing advanced low-fouling coatings.

Estimation of SPIO Nanoparticles Uptakes by Macrophages Using Transmission Electron Microscopy

Due to their interesting size-dependent magnetic characteristics and relative biocompatibility, magnetic superparamagnetic iron oxide (SPIO) nanoparticles have been widely exploited as probes for cell and subcellular structure identification, as well as medication and gene delivery. A thorough understanding of the mechanics of the interaction between nanoparticles and macrophages is vital in managing dynamic processes in nanomedicine. In this study, the interaction behavior and uptake of SPIO nanoparticles by M1- and M2-type macrophages were investigated. Mice monocytes were differentiated into M1 and M2 macrophages, and the uptake of SPIO nanoparticles was studied using a TEM microscope. A high resolution image of 1 nm resolution, an image processing technique, was developed to extract the SPIO-NPs from tomographic TEM microscopic images. Lysosomes appear to be the zones of high concentrations of SPIO inside macrophages. Lysosomes were first selected in each image, and then segmentation by the Otsu thresholding method was used to extract the SPIO-NPs. The Otsu threshold method is a global thresholding technique used to automatically differentiate SPIOs from the background. The SPIO-NPs appear in red colors, and the other pixels in the image are considered background. Then, an estimation of the SPIO-NP uptakes by lysosomes is produced. Higher uptake of all-sized nanoparticles was observed in M1- and M2-type macrophages. An accurate estimation of the number of SPIO-NPs was obtained. This result will help in controlling targeted drug delivery and assessing the safety impact of the use of SPIO-NPs in nanomedicine for humans.

Stealth nanoparticles in oncology: Facing the PEG dilemma

Nanoparticles (Nps) have revolutionized the landscape of many treatments, by modifying not only pharmacokinetic properties of the encapsulated agent, but also providing a significant protection of the drug from non-desired interactions, and reducing side-effects of the enclosed therapeutic, enabling co-encapsulation of possibly synergistic compounds or activities, allowing a controlled release of content and improving the therapeutic effect. Nevertheless, in systemic circulation, Nps suffer a rapid removal by opsonisation and the action of Mononuclear phagocyte system (MPS). To overcome this problem, different polymers, in particular Polyethyleneglycol (PEG), have been used to cover the surface of these nanocarriers forming a hydrophilic layer that allows the delay of the removal. These advantages contrast with some drawbacks such as the difficulty to interact with cell membranes and the development of immunological reactions, conforming the known, "PEG dilemma". To address and minimize this phenomenon, different strategies have been applied. Therefore, this review aims to summarize the state of the art of Pegylation strategies, comment in depth on the principal characteristics of PEG and describe the main alternatives, which are the use of cleavable PEG, addition of different polymers or even use other derivatives of cell membranes to camouflage Nps.

In situ analysis of nanoparticle soft corona and dynamic evolution

How soft corona, the protein corona’s outer layer, contributes to biological identity of nanomaterials is largely because capturing protein composition of the soft corona in situ remains challenging. We herein develop an in situ Fishing method that can monitor the dynamic formation of protein corona on ultra-small chiral Cu₂S nanoparticles (NPs) allowing us to directly separate and identify the corona protein composition. Our method detects spatiotemporal processes in the evolution of hard and soft coronas on chiral NPs, revealing subtle differences in NP − protein interactions even within several minutes. This study highlights the importance of in situ and dynamic analysis of soft/hard corona, provides insights into the role of soft corona in mediating biological responses of NPs, and offers a universal strategy to characterize soft corona to guide the rational design of biomedical nanomaterials.

Characterizing the soft protein corona on nanoparticles i.e. the outer layer of the corona, remains a longstanding challenge. Here, the authors develop an in situ method to monitor the dynamic processes of multilayered corona formation and evolution that offers a universal strategy to characterize the soft corona proteome.

The protein corona reduces the anticancer effect of graphene oxide in HER-2-positive cancer cells

In the last decade, graphene oxide (GO)-based nanomaterials have attracted much attention for their potential anti-cancer properties against various cancer cell types. However, while in vitro studies are promising, following in vivo investigations fail to show any relevant efficacy. Recent research has clarified that the wide gap between benchtop discoveries and clinical practice is due to our limited knowledge about the physical-chemical transformation of nanomaterials in vivo. In physiological environments, nanomaterials are quickly coated by a complex dress of biological molecules referred to as the protein corona. Mediating the interaction between the pristine material and the biological system the protein corona controls the mechanisms of action of nanomaterials up to the sub-cellular level. Here we investigate the anticancer ability of GO in SK-BR-3 human breast cancer cells over-expressing the human epidermal growth factor receptor 2 (HER-2), which is functionally implicated in the cell growth and proliferation through the activation of downstream pathways, including the PI3K/AKT/mTOR and MAPK/ERK signaling cascades. Western blot analysis demonstrated that GO treatment resulted in a marked decrease in total HER-2, associated with a down-regulation of the expression and activation of protein kinase B (AKT) and extracellular signal-regulated kinase (ERK) thus indicating that GO may act as a potent HER-2 inhibitor. On the other side, the protein corona reverted the effects of GO on HER-2 expression and molecular downstream events to the control level. Our findings may suggest a mechanistic explanation of the reduced anticancer properties of GO-based nanomaterials in vivo. These results may also represent a good prediction strategy for the anticancer activity of nanomaterials designed for biomedical purposes, reaffirming the necessity of exploring their effectiveness under physiologically relevant conditions before moving on to the next in vivo studies.

Polyglycerol Functionalized 10 B Enriched Boron Carbide Nanoparticle as an Effective Bimodal Anticancer Nanosensitizer for Boron Neutron Capture and Photothermal Therapies

Boron neutron capture therapy (BNCT) is a non-invasive cancer treatment with little adverse effect utilizing nuclear fission of ¹⁰ B upon neutron irradiation. While neutron source has been developed from a nuclear reactor to a compact accelerator, only two kinds of drugs, boronophenylalanine and sodium borocaptate, have been clinically used for decades despite their low tumor specificity and/or retentivity. To overcome these challenges, various boron-containing nanomaterials, or "nanosensitizers", have been designed based on micelles, (bio)polymers and inorganic nanoparticles. Among them, inorganic nanoparticles such as boron carbide can include a much higher ¹⁰ B content, but successful in vivo applications are very limited. Additionally, recent reports on the photothermal effect of boron carbide are motivating for the addition of another modality of photothermal therapy. In this study, ¹⁰ B enriched boron carbide (¹⁰ B₄ C) nanoparticle is functionalized with polyglycerol (PG), giving ¹⁰ B₄ C-PG with enough dispersibility in a physiological environment. Pharmacokinetic experiments show that ¹⁰ B₄ C-PG fulfills the following three requirements for BNCT; 1) low intrinsic toxicity, 2) ¹⁰ B in tumor/tumor tissue (wt/wt) ≥ 20 ppm, and 3) ¹⁰ B concentrations in tumor/blood ≥ 3. In vivo study reveals that neutron irradiation after intravenous administration of ¹⁰ B₄ C-PG suppresses cancer growth significantly and eradicates cancer with the help of near-infrared light irradiation.

Lubricant-entrenched Slippery Surface-based Nanocarriers to Avoid Macrophage Uptake and Improve Drug Utilization

INTRODUCTION

Reducing the protein adsorption of nanoparticles (NPs) as drug carriers to slow their rapid clearance by macrophages uptake is a critical challenge for NPs clinical translational applications. Despite extensive research efforts to inhibit cellular uptake, including covering biological agents or surface chemical coatings to impart "stealth" properties to NPs, their stability remains insufficient.

OBJECTIVES

Developed a novel surface modification technology based on a physical infusion engineering approach to achieve persistent inhibition of protein adhesion and cellular uptake by nanocarriers.

METHODS

The nanoparticles were prepared based on conventional drug carrier mesoporous silica NPs through a two-step process. A functional nanoscale slippery surface was formed by grafting "liquid-like" brushes on the particles surface, and then a lubricant-entrenched slippery surfaces (LESS) was formed by infusing silicone oil lubricant into the entire surface. Co-incubation with macrophages (in vitro and in vivo) was used to examine the anti-uptake properties of modified NPs. The anti-adhesion properties of LESS coating surfaces to various liquids, proteins and cells were used to analyze the anti-uptake mechanism. Loaded with drugs, combined with tumor models, to evaluate the drug utilization of modified NPs.

RESULTS

Relying on the stable and slippery LESS coating, the modified surface could prevent the adhesion of various liquids and effectively shield against the adhesion of proteins and cells, as well as remarkably reduce macrophage cellular uptake in vitro and in vivo. In addition, the LESS coating does not affect cell activity and allows NPs to be loaded with drugs, significantly improving the utilization of drugs in vitro and in vivo. This allows the NPs to reach to the target tumor site for drug delivery without active clearance by macrophages.

CONCLUSION

Our research introduces a new nanocarrier technology to improve anti-biofouling performance and stealth efficiency that will facilitate the development of nanomedicines for clinical transformation applications.

Polyglycerol fatty acid esters as alternatives to PEGylated lipids for liposome coating

Background: Polyglycerol (PG) is a type of biocompatible hydrophilic polyether polyol, and it is considered as a potential alternative to polyethylene glycol (PEG) in modifying nanomedicines. Materials & methods: Polyglycerol fatty acid esters (PGFEs) were modified onto liposomes and their serum stability, pharmacokinetics, in vivo distribution and the capacity to induce anti-PEG IgM were compared with PEGylated liposomes (PEG-Lips). Results: Polyglycerol 10-monostearate (PG-10-MS) displayed considerable serum stability and compatibility with mice red blood cells, and it significantly prolonged the blood circulation of liposomes in the pharmacokinetics study compared with the unmodified liposomes, with a similar biodistribution pattern to that of the PEG-Lips. Moreover, PGFE-modified liposomes were less likely to induce the production of anti-PEG IgM. Conclusion: PGFEs could be considered as good candidates to replace PEG lipids for the preparation of liposomes.

Low-Fouling Gold Nanorod Theranostic Agents Enabled by a Sulfoxide Polymer Coating

Gold nanorods (GNRs) are widely used in various biomedical applications such as disease imaging and therapy due to their unique plasmonic properties. To improve their bioavailability, GNRs often need to be coated with hydrophilic polymers so as to impart stealth properties. Poly(ethylene glycol) (PEG) has been long used as such a coating material for GNRs. However, there is increasing acknowledgement that the amphiphilic nature of PEG facilitates its interaction with protein molecules, leading to immune recognition and consequent side effects. This has motivated the search for new classes of low-fouling polymers with high hydrophilicity as alternative low-fouling surface coating materials for GNRs. Herein, we report the synthesis, characterization, and application of GNRs coated with highly hydrophilic sulfoxide-containing polymers. We investigated the effect of the sulfoxide polymer coating on the cellular uptake and in vivo circulation time of the GNRs and compared these properties with pegylated GNR counterparts. The photothermal effect and photoacoustic imaging of these polymer-coated GNRs were also explored, and the results show that these GNRs are promising as nanotheranostic particles for the treatment of cancer.

Inducible endothelial leakiness in nanotherapeutic applications

All intravenous delivered nanomedicine needs to escape from the blood vessel to exert their therapeutic efficacy at their designated site of action. Failure to do so increases the possibility of detrimental side effects and negates their therapeutic intent. Many powerful anticancer nanomedicine strategies rely solely on the tumor derived enhanced permeability and retention (EPR) effect for the only mode of escaping from the tumor vasculature. However, not all tumors have the EPR effect nor can the EPR effect be induced or controlled for its location and timeliness. In recent years, there have been exciting developments along the lines of inducing endothelial leakiness at the tumor to decrease the dependence of EPR. Physical disruption of the endothelial-endothelial cell junctions with coordinated biological intrinsic pathways have been proposed that includes various modalities like ultrasound, radiotherapy, heat and even nanoparticles, appear to show good progress towards the goal of inducing endothelial leakiness. This review explains the intricate and complex biological background behind the endothelial cells with linkages on how updated reported nanomedicine strategies managed to induce endothelial leakiness. This review will also end off with fresh insights on where the future of inducible endothelial leakiness holds.

Polyglycerol and Poly(ethylene glycol) exhibit different effects on pharmacokinetics and antibody generation when grafted to nanoparticle surfaces

Poly(ethylene glycol) (PEG) is widely employed for passivating nanoparticle (NP) surfaces to prolong blood circulation and enhance localization of NPs to target tissue. However, the immune response of PEGylated NPs-including anti-PEG antibody generation, accelerated blood clearance (ABC), and loss of delivery efficacy-is of some concern, especially for treatments that require repeat administrations. Although polyglycerol (PG), which has the same ethylene oxide backbone as PEG, has received attention as an alternative to PEG for NP coatings, the pharmacokinetic and immunogenic impact of PG has not been studied systematically. Here, linear PG, hyperbranched PG (hPG), and PEG-coated polylactide (PLA) NPs with varying surface densities were studied in parallel to determine the pharmacokinetics and immunogenicity of PG and hPG grafting, in comparison with PEG. We found that linear PG imparted the NPs a stealth property comparable to PEG, while hPG-grafted NPs needed a higher surface density to achieve the same pharmacokinetic impact. While linear PG-grafted NPs induced anti-PEG antibody production in mice, they exhibited minimal accelerated blood clearance (ABC) effects due to the poor interaction with anti-PEG immunoglobulin M (IgM). Further, we observed no anti-polymer IgM responses or ABC effects for hPG-grafted NPs.

Intrinsically Disordered Protein Condensate-Modified Surface for Mitigation of Biofouling and Foreign Body Response

Mitigation of biofouling and the host's foreign body response (FBR) is a critical challenge with biomedical implants. The surface coating with various anti-fouling materials provides a solution to overcome it, but limited options in clinic and their potential immunogenicity drive the development of more alternative coating materials. Herein, inspired by liquid-liquid phase separation of intrinsically disordered proteins (IDPs) to form separated condensates in physiological conditions, we develop a new type of low-fouling biomaterial based on flexible IDP of FUS protein containing rich hydrophilic residues. A chemical structure-defined FUS IDP sequence tagged with a tetra-cysteine motif (IDP_FUS) was engineered and applied for covalent immobilization on various surfaces to form a uniform layer of protein tangles, which boosted strong hydration on surfaces, as revealed by molecular dynamics simulation. The IDP_FUS-coated surfaces displayed excellent performance in resisting adsorption of various proteins and adhesion of different cells, platelets, and bacteria. Moreover, the IDP_FUS-coated implants largely mitigated the host's FBR compared with bare implants and particularly outperformed PEG-coated implants in reducing collagen encapsulation. Thus, this novel low-fouling and anti-FBR strategy provides a potential surface coating material for biomedical implants, which will also shed light on exploring similar applications of other IDP proteins.

The protein corona modulates the inflammation inhibition by cationic nanoparticles via cell-free DNA scavenging

A central paradigm in nanomedicine is that when synthetic nanoparticles (NPs) enter the body, they are immediately cloaked by a corona of macromolecules (mostly proteins) that mediates the role of the physico-chemical properties in the NP biological functions (the “coronation paradigm”). In this work, we focused on the assessment of the “coronation paradigm” for cationic NPs (cNPs) used as rheumatoid arthritis (RA) drugs due to their ability to scavenge cell-free DNA (cfDNA). We fabricated series of cNPs uniformly coated with single or di-hydroxyl groups and different types of amino groups and showed that hydroxylated nanoparticles displayed a prolonged retention in inflamed joints and greater anti-inflammatory effect in collagen-induced arthritis (CIA) rats than the non-hydroxylated analogues. Especially, the cNPs with secondary amines and a di-hydroxyl shell showed the best performance among the tested cNPs. Proteomic analysis showed that the cNPs with a di-hydroxyl shell adsorbed less opsonin proteins than the cNPs carrying mono hydroxyl groups and non-hydroxylated ones, which may provide a mechanistic explanation for the different biodistribution profiles of cNPs. Thus, this study suggests that the protein corona mediates the effects of the surface chemistry on the fate and functions of cNPs as anti-RA drugs.

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cNPs with hydroxyl shell decreased side-effects to cells and CIA rats without decreasing the ability to scavenge cfDNA.

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Hydroxyl shell reduced the adsorption of proteins, thus prolonged the circulation and site accumulation of cNPs.

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The composition of the protein corona formed onto the cNPs in the serum can be modulated by their synthetic identity.

Artificial engineering of the protein corona at bio-nano interfaces for improved cancer-targeted nanotherapy

Nanoparticles (NPs) have been demonstrated in numerous applications as anticancer, antibacterial and antioxidant agents. Artificial engineering of protein interactions with NPs in biological systems is crucial to develop potential NPs for drug delivery and cancer nanotherapy. The protein corona (PC) on the NP surface, displays an interface between biomacromolecules and NPs, governing their pharmacokinetics and pharmacodynamics. Upon interaction of proteins with the NP surface, their surface features are modified and they can easily be removed from the circulation by the mononuclear phagocytic system (MPS). PC properties heavily depend on the biological microenvironment and NP surface physicochemical parameters. Based on this context, we have surveyed different approaches that have been used for artificial engineering of the PC composition on NP surfaces. We discuss the effects of NP size, shape, surface modifications (PEGylation, self-peptide, other polymers), and protein pre-coating on the PC properties. Additionally, other factors including protein source and structure, intravenous injection and the subsequent shear flow, plasma protein gradients, temperature and local heat transfer, and washing media are considered in the context of their effects on the PC properties and overall target cellular effects. Moreover, the effects of NP-PC complexes on cancer cells based on cellular interactions, organization of intracellular PC (IPC), targeted drug delivery (TDD) and regulation of burst drug release profile of nanoplatforms, enhanced biocompatibility, and clinical applications were discussed followed by challenges and future perspective of the field. In conclusion, this paper can provide useful information to manipulate PC properties on the NP surface, thus trying to provide a literature survey to shorten their shipping from preclinical to clinical trials and to lay the basis for a personalized PC.

Nanoparticle personalized biomolecular corona: implications of pre-existing conditions for immunomodulation and cancer

Nanoparticles (NPs) have demonstrated great promise as immunotherapies for applications ranging from cancer, autoimmunity, and infectious disease. Upon encountering biological fluids, NPs rapidly adsorb biomolecules, forming the "biomolecular corona" (BC), and the altered character of NPs due to their newly acquired biological identity can impact their in vivo fate. Recently, it has been shown that the NP-BC is person-specific, and even minute differences in the biomolecule composition can give rise to altered immune recognition, cellular interactions, pharmacokinetics, and biodistribution. Given the current rise in the development of NP-based therapeutics, it is of utmost importance to better understand how pre-existing conditions, that result in the formation of a personalized BC, can be leveraged to aid in the prediction of the therapeutic outcomes of NPs. In this minireview, we will discuss the formation of the BC, implications of the BC for NP-biological interactions, and its clinical importance in the context of immunomodulation and cancer therapeutics.

Protein adsorption onto nanomaterials engineered for theranostic applications

The key role of biomolecule adsorption onto engineered nanomaterials for therapeutic and diagnostic purposes has been well recognized by the nanobiotechnology community, and our mechanistic understanding of nano-bio interactions has greatly advanced over the past decades. Attention has recently shifted to gaining active control of nano-bio interactions, so as to enhance the efficacy of nanomaterials in biomedical applications. In this review, we summarize progress in this field and outline directions for future development. First, we briefly review fundamental knowledge about the intricate interactions between proteins and nanomaterials, as unraveled by a large number of mechanistic studies. Then, we give a systematic overview of the ways that protein-nanomaterial interactions have been exploited in biomedical applications, including the control of protein adsorption for enhancing the targeting efficiency of nanomedicines, the design of specific protein adsorption layers on the surfaces of nanomaterials for use as drug carriers, and the development of novel nanoparticle array-based sensors based on nano-bio interactions. We will focus on particularly relevant and recent examples within these areas. Finally, we conclude this topical review with an outlook on future developments in this fascinating research field.

The Janus of Protein Corona on nanoparticles for tumor targeting, immunotherapy and diagnosis

The therapeutics based on nanoparticles (NPs) are considered as the promising strategy for tumor detection and treatment. However, one of the most challenges is the adsorption of biomolecules on NPs after their exposition to biological medium, leading unpredictable in vivo behaviors. The interactions caused by protein corona (PC) will influence the biological fate of NPs in either negative or positive ways, including (i) blood circulation, accumulation and penetration of NPs at targeting sites, and further cellular uptake in tumor targeting delivery; (ii) interactions between NPs and receptors on immune cells for immunotherapy. Besides, PC on NPs could be utilized as new biomarker in tumor diagnosis by identifying the minor change of protein concentration led by tumor growth and invasion in blood. Herein, the mechanisms of these PC-mediated effects will be introduced. Moreover, the recent advances about the strategies will be reviewed to reduce negative effects caused by PC and/or utilize positive effects of PC on tumor targeting, immunotherapy and diagnosis, aiming to provide a reasonable perspective to recognize PC with their applications.

Targeted Drug Delivery for the Treatment of Blood Cancers

Blood cancers are a type of liquid tumor which means cancer is present in the body fluid. Multiple myeloma, leukemia, and lymphoma are the three common types of blood cancers. Chemotherapy is the major therapy of blood cancers by systemic administration of anticancer agents into the blood. However, a high incidence of relapse often happens, due to the low efficiency of the anticancer agents that accumulate in the tumor site, and therefore lead to a low survival rate of patients. This indicates an urgent need for a targeted drug delivery system to improve the safety and efficacy of therapeutics for blood cancers. In this review, we describe the current targeting strategies for blood cancers and recently investigated and approved drug delivery system formulations for blood cancers. In addition, we also discuss current challenges in the application of drug delivery systems for treating blood cancers.