Biosafety and bioapplication of nanomaterials by designing protein-nanoparticle interactions

Ultrasound-Based Micro-/Nanosystems for Biomedical Applications

Due to the intrinsic non-invasive nature, cost-effectiveness, high safety, and real-time capabilities, besides diagnostic imaging, ultrasound as a typical mechanical wave has been extensively developed as a physical tool for versatile biomedical applications. Especially, the prosperity of nanotechnology and nanomedicine invigorates the landscape of ultrasound-based medicine. The unprecedented surge in research enthusiasm and dedicated efforts have led to a mass of multifunctional micro-/nanosystems being applied in ultrasound biomedicine, facilitating precise diagnosis, effective treatment, and personalized theranostics. The effective deployment of versatile ultrasound-based micro-/nanosystems in biomedical applications is rooted in a profound understanding of the relationship among composition, structure, property, bioactivity, application, and performance. In this comprehensive review, we elaborate on the general principles regarding the design, synthesis, functionalization, and optimization of ultrasound-based micro-/nanosystems for abundant biomedical applications. In particular, recent advancements in ultrasound-based micro-/nanosystems for diagnostic imaging are meticulously summarized. Furthermore, we systematically elucidate state-of-the-art studies concerning recent progress in ultrasound-based micro-/nanosystems for therapeutic applications targeting various pathological abnormalities including cancer, bacterial infection, brain diseases, cardiovascular diseases, and metabolic diseases. Finally, we conclude and provide an outlook on this research field with an in-depth discussion of the challenges faced and future developments for further extensive clinical translation and application.

Protein Corona Composition of Gold Nanocatalysts

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

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

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

Impact of calcium ions at physiological concentrations on the adsorption behavior of proteins on silica nanoparticles

The adsorption of proteins on nanoparticles (NPs) largely decides the fate and bioeffects of NPs in vivo. However, bio-fluids are too complicated to directly study in them to reveal related mechanisms, and current studies on model systems often ignore some important biological factors, such as metal ions. Herein, we evaluate the effect of Ca2+ at physiological concentrations on the protein adsorption on negatively-charged silica NP (SNP50). It is found that Ca2+, as well as Mg2+ and several transition metal ions, significantly enhances the adsorption of negatively-charged proteins on SNP50. Moreover, the Ca2+-induced enhancement of protein adsorption leads to the reduced uptake of SNP50 by HeLa cells. A double-chelating mechanism is proposed for the enhanced adsorption of negatively-charged proteins by multivalent metal ions that can form 6 (or more) coordinate bonds, where the metal ions are chelated by both the surface groups of NPs and the surface residues of the adsorbed proteins. This mechanism is consistent with all experimental evidences from metal ions-induced changes of physicochemical properties of NPs to protein adsorption isotherms, and is validated with several model proteins as well as complicated serum. The findings highlight the importance of investigating the influences of physiological factors on the interaction between proteins and NPs.

Nanovaccines for Advancing Long-Lasting Immunity against Infectious Diseases

Infectious diseases, particularly life-threatening pathogens such as small pox and influenza, have substantial implications on public health and global economies. Vaccination is a key approach to combat existing and emerging pathogens. Immunological memory is an essential characteristic used to evaluate vaccine efficacy and durability and the basis for the long-term effects of vaccines in protecting against future infections; however, optimizing the potency, improving the quality, and enhancing the durability of immune responses remains challenging and a focus for research involving investigation of nanovaccine technologies. In this review, we describe how nanovaccines can address the challenges for conventional vaccines in stimulating adaptive immune memory responses to protect against reinfection. We discuss protein and nonprotein nanoparticles as useful antigen platforms, including those with highly ordered and repetitive antigen array presentation to enhance immunogenicity through cross-linking with multiple B cell receptors, and with a focus on antigen properties. In addition, we describe how nanoadjuvants can improve immune responses by providing enhanced access to lymph nodes, lymphnode targeting, germinal center retention, and long-lasting immune response generation. Nanotechnology has the advantage to facilitate vaccine induction of long-lasting immunity against infectious diseases, now and in the future.

Formation and detection of biocoronas in the food industry and their fate in the human body

The rapid advancement of nanotechnology has opened up new avenues for applications in all stages of the food industry. Over the past decade, extensive research has emphasized that when nanoparticles (NPs) enter organisms, they spontaneously adsorbed biomolecules, leading to the formation of biocorona. This paper provided a detailed review of the process of biocorona formation in the food industry, including their classification and influencing factors. Additionally, various characterization methods to investigated the morphology and structure of biocoronas were introduced. As a real state of food industry nanoparticles in biological environments, the biocorona causes structural transformations of biomolecules bound to NPs, thus affecting their fate in the body. It can either promote or inhibit enzyme activity in the human environment, and may also positively or negatively affect the cellular uptake and toxicity of NPs. Since NPs present in the food industry will inevitably enter the human body, further investigations on biocoronas will offer valuable insights and perspectives on the safety of incorporating more NPs into the food industry.

Uptake of extracellular vesicles into immune cells is enhanced by the protein corona

The influence of a protein corona on the uptake of nanoparticles in cells has been demonstrated in various publications over the last years. Extracellular vesicles (EVs), can be seen as natural nanoparticles. However, EVs are produced under different cell culture conditions and little is known about the protein corona forming on EVs and its influence on their uptake by target cells. Here, we use a proteomic approach in order to analyze the protein composition of the EVs themselves and the protein composition of a human blood plasma protein corona around EVs. Moreover, we analyze the influence of the protein corona on EV uptake into human monocytes and compare it with the influence on the uptake of engineered liposomes. We show that the presence of a protein corona increases the uptake of EVs in human monocytes. While for liposomes this seems to be triggered by the presence of immunoglobulins in the protein corona, for EVs blocking the Fc receptors on monocytes did not show an influence of uptake. Therefore, other mechanisms of docking to the cell membrane and uptake are most like involved, demonstrating a clear difference between EVs and liposomes as technically produced nanocarriers.

Biomedical Approach of Nanotechnology and Biological Risks: A Mini-Review

Nanotechnology has played a prominent role in biomedical engineering, offering innovative approaches to numerous treatments. Notable advances have been observed in the development of medical devices, contributing to the advancement of modern medicine. This article briefly discusses key applications of nanotechnology in tissue engineering, controlled drug release systems, biosensors and monitoring, and imaging and diagnosis. The particular emphasis on this theme will result in a better understanding, selection, and technical approach to nanomaterials for biomedical purposes, including biological risks, security, and biocompatibility criteria.

Self-driven immune checkpoint blockade and spatiotemporal-sensitive immune response monitoring in acute myeloid leukemia using an all-in-one turn-on bionanoprobe

Immune checkpoint (ICP) blockade (ICB) is one of the most promising immunotherapies for acute myeloid leukemia (AML). However, owing to their heterogeneity, AML cells may cause uncoordinated metabolic fluxes and heterogeneous immune responses, inducing the release of a spatiotemporally sensitive immune response marker. Timely and in situ detection of immune responses in ICB therapy is important for therapeutic strategy adjustment. Herein, we constructed an all-in-one nanoprobe for self-driving ICB and simultaneously detecting an immune response in the same AML cell in vivo, thus enabling accurate evaluation of heterogenetic immune responses in living AML mice without additional drug treatment or probe processes. The nature-inspire polydopamine (PDA) nanoparticles loaded with an ICP blocker were targeted to the leukocyte immunoglobulin like receptor B4 (a new ICP) of AML cells to induce the release of immune response marker granzyme B (GrB). The PDA nanoparticles were additionally paired with carbon-derived graphene quantum dots (GQDs) to construct a full-organic 'turn-on' bionanoprobe that can transfer fluorescence resonance energy for GrB detection. This multifunctional nanoprobe was validated for triggering ICB therapy and monitoring the changes of GrB levels in real-time both in vitro and in vivo. The organic nanoprobe showed excellent permeability and retention in tumor cells and high biocompatibility in vivo. This bionanoprobe orderly interacted with the upstream ICP molecules and downstream signal molecule GrB, thereby achieving in situ immune response signals within the therapeutic efficacy evaluation window.

Simultaneous Electrophysiology and Imaging Reveal Changes in Lipid Membrane Thickness and Tension upon Uptake of Amphiphilic Gold Nanoparticles

Amphiphilic gold core nanoparticles (AmNPs) striped with hydrophilic 11-mercapto-1-undecanesulfonate (MUS) and hydrophobic 1-octanethiol (OT) ligands are promising candidates for drug carriers that passively and nondisruptively enter cells. Yet, how they interact with cellular membranes is still only partially understood. Herein, we use electrophysiology and imaging to carefully assess changes in droplet interface bilayer lipid membranes (DIBs) incurred by striped AmNPs added via microinjection. We find that AmNPs spontaneously reduce the steady-state specific capacitance and contact angle of phosphatidylcholine DIBs by amounts dependent on the final NP concentration. These reductions, which are greater for NPs with a higher % OT ligands and membranes containing unsaturated lipids but negligible for MUS-only-coated NPs, reveal that AmNPs passively embed in the interior of the bilayer where they increase membrane thickness and lateral tension through disruption of lipid packing. These results demonstrate the enhanced evaluation of nano-bio interactions possible via electrophysiology and imaging of DIBs.

Secured delivery of basic fibroblast growth factor using human serum albumin-based protein nanoparticles for enhanced wound healing and regeneration

BACKGROUND

Basic fibroblast growth factor (bFGF) is one of the critical components accelerating angiogenesis and tissue regeneration by promoting the migration of dermal fibroblasts and endothelial cells associated with matrix formation and remodeling in wound healing process. However, clinical applications of bFGF are substantially limited by its unstable nature due to rapid decomposition under physiological microenvironment.

RESULTS

In this study, we present the bFGF-loaded human serum albumin nanoparticles (HSA-bFGF NPs) as a means of enhanced stability and sustained release platform during tissue regeneration. Spherical shape of the HSA-bFGF NPs with uniform size distribution (polydispersity index < 0.2) is obtained via a simple desolvation and crosslinking process. The HSA-bFGF NPs securely load and release the intact soluble bFGF proteins, thereby significantly enhancing the proliferation and migration activity of human dermal fibroblasts. Myofibroblast-related genes and proteins were also significantly down-regulated, indicating decrease in risk of scar formation. Furthermore, wound healing is accelerated while achieving a highly organized extracellular matrix and enhanced angiogenesis in vivo.

CONCLUSION

Consequently, the HSA-bFGF NPs are suggested not only as a delivery vehicle but also as a protein stabilizer for effective wound healing and tissue regeneration.

Protein corona investigations of polyplexes with varying hydrophobicity - From method development to in vitro studies

In the field of non-viral drug delivery, polyplexes (PXs) represent an advanced investigated and highly promising tool for the delivery of nucleic acids. Upon encountering physiological fluids, they adsorb biological molecules to form a protein corona (PC), that influence PXs biodistribution, transfection efficiencies and targeting abilities. In an effort to understand protein - PX interactions and the effect of PX material on corona composition, we utilized cationic branched 10 kDa polyethyleneimine (b-PEI) and a hydrophobically modified nylon-3 polymer (NM0.2/CP0.8) within this study to develop appropriate methods for PC investigations. A centrifugation procedure for isolating hard corona - PX complexes (PCPXs) from soft corona proteins after incubating the PXs in fetal bovine serum (FBS) for PC formation was successfully optimized and the identification of proteins by a liquid chromatography-tandem mass spectrometry (LC-MS-MS) method clearly demonstrated that the PC composition is affected by the underlying PXs material. With regard to especially interesting functional proteins, which might be able to induce active targeting effects, several candidates could be detected on b-PEI and NM0.2/CP0.8 PXs. These results are of high interest to better understand how the design of PXs impacts the PC composition and subsequently PCPXs-cell interactions to enable precise adjustment of PXs for targeted drug delivery.

The role of protein corona on nanodrugs for organ-targeting and its prospects of application

Nowadays, nanodrugs become a hotspot in the high-end medical field. They have the ability to deliver drugs to reach their destination more effectively due to their unique properties and flexible functionalization. However, the fate of nanodrugs in vivo is not the same as those presented in vitro, which indeed influenced their therapeutic efficacy in vivo. When entering the biological organism, nanodrugs will first come into contact with biological fluids and then be covered by some biomacromolecules, especially proteins. The proteins adsorbed on the surface of nanodrugs are known as protein corona (PC), which causes the loss of prospective organ-targeting abilities. Fortunately, the reasonable utilization of PC may determine the organ-targeting efficiency of systemically administered nanodrugs based on the diverse expression of receptors on cells in different organs. In addition, the nanodrugs for local administration targeting diverse lesion sites will also form unique PC, which plays an important role in the therapeutic effect of nanodrugs. This article introduced the formation of PC on the surface of nanodrugs and summarized the recent studies about the roles of diversified proteins adsorbed on nanodrugs and relevant protein for organ-targeting receptor through different administration pathways, which may deepen our understanding of the role that PC played on organ-targeting and improve the therapeutic efficacy of nanodrugs to promote their clinical translation.

Harnessing Hafnium-Based Nanomaterials for Cancer Diagnosis and Therapy

With the rapid development of nanotechnology and nanomedicine, there are great interests in employing nanomaterials to improve the efficiency of disease diagnosis and treatment. The clinical translation of hafnium oxide (HfO2 ), commercially namedas NBTXR3, as a new kind of nanoradiosensitizer for radiotherapy (RT) of cancers has aroused extensive interest in researches on Hf-based nanomaterials for biomedical application. In the past 20 years, Hf-based nanomaterials have emerged as potential and important nanomedicine for computed tomography (CT)-involved bioimaging and RT-associated cancer treatment due to their excellent electronic structures and intrinsic physiochemical properties. In this review, a bibliometric analysis method is employed to summarize the progress on the synthesis technology of various Hf-based nanomaterials, including HfO2 , HfO2 -based compounds, and Hf-organic ligand coordination hybrids, such as metal-organic frameworks or nanoscaled coordination polymers. Moreover, current states in the application of Hf-based CT-involved contrasts for tissue imaging or cancer diagnosis are reviewed in detail. Importantly, the recent advances in Hf-based nanomaterials-mediated radiosensitization and synergistic RT with other current mainstream treatments are also generalized. Finally, current challenges and future perspectives of Hf-based nanomaterials with a view to maximize their great potential in the research of translational medicine are also discussed.

Exocytosis of Nanoparticles: A Comprehensive Review

Both biomedical applications and safety assessments of manufactured nanomaterials require a thorough understanding of the interaction between nanomaterials and cells, including how nanomaterials enter cells, transport within cells, and leave cells. However, compared to the extensively studied uptake and trafficking of nanoparticles (NPs) in cells, less attention has been paid to the exocytosis of NPs. Yet exocytosis is an indispensable process of regulating the content of NPs in cells, which in turn influences, even decides, the toxicity of NPs to cells. A comprehensive understanding of the mechanisms and influencing factors of the exocytosis of NPs is not only essential for the safety assessment of NPs but also helpful for guiding the design of safe and highly effective NP-based materials for various purposes. Herein, we review the current status and progress of studies on the exocytosis of NPs. Firstly, we introduce experimental procedures and considerations. Then, exocytosis mechanisms/pathways are summarized with a detailed introduction of the main pathways (lysosomal and endoplasmic reticulum/Golgi pathway) and the role of microtubules; the patterns of exocytosis kinetics are presented and discussed. Subsequently, the influencing factors (initial content and location of intracellular NPs, physiochemical properties of NPs, cell type, and extracellular conditions) are fully discussed. Although there are inconsistent results, some rules are obtained, like smaller and charged NPs are more easily excreted. Finally, the challenges and future directions in the field have been discussed.

Ecotoxicological significance of bio-corona formation on micro/nanoplastics in aquatic organisms

The unsustainable manufacturing, utilization and inadequate handling of plastics have led to a surge in global plastic pollution. In recent times, there has been increasing concern about the plausible hazards associated with exposure to micro/nanoplastics (M/NPs). As aquatic systems are considered to be the likely sink for M/NPs, it is crucial to comprehend their environmental behavior. The bioavailability, toxicity and fate of M/NPs in the environment are predominantly dictated by their surface characteristics. In the aquatic environment, M/NPs are prone to be internalized by aquatic organisms. This may facilitate their interaction with a diverse array of biomolecules within the organism, resulting in the formation of a biocorona (BC). The development of BC causes modifications in the physicochemical attributes of the M/NPs including changes to their size, stability, surface charge and other properties. This review details the concept of BC formation and its underlying mechanism. It provides insight on the analytical techniques employed for characterizing BC formation and addresses the associated challenges. Further, the eco-toxicological implications of M/NPs and the role of BC in modifying their potential toxicity on aquatic organisms is specified. The impact of BC formation on the fate and transport of M/NPs is discussed. A concise outlook on the future perspectives is also presented.

Functionalization of and through Melanin: Strategies and Bio-Applications

A unique feature of nanoparticles for bio-application is the ease of achieving multi-functionality through covalent and non-covalent functionalization. In this way, multiple therapeutic actions, including chemical, photothermal and photodynamic activity, can be combined with different bio-imaging modalities, such as magnetic resonance, photoacoustic, and fluorescence imaging, in a theragnostic approach. In this context, melanin-related nanomaterials possess unique features since they are intrinsically biocompatible and, due to their optical and electronic properties, are themselves very efficient photothermal agents, efficient antioxidants, and photoacoustic contrast agents. Moreover, these materials present a unique versatility of functionalization, which makes them ideal for the design of multifunctional platforms for nanomedicine integrating new functions such as drug delivery and controlled release, gene therapy, or contrast ability in magnetic resonance and fluorescence imaging. In this review, the most relevant and recent examples of melanin-based multi-functionalized nanosystems are discussed, highlighting the different methods of functionalization and, in particular, distinguishing pre-functionalization and post-functionalization. In the meantime, the properties of melanin coatings employable for the functionalization of a variety of material substrates are also briefly introduced, especially in order to explain the origin of the versatility of melanin functionalization. In the final part, the most relevant critical issues related to melanin functionalization that may arise during the design of multifunctional melanin-like nanoplatforms for nanomedicine and bio-application are listed and discussed.

Pre-exposure to titanium or iron oxide nanoparticles suppresses the subsequent cellular uptake of gold nanoparticles

Humans are exposed to a wide variety of natural and engineered nanoparticles (NPs) during their lifetime. However, the effects of pre-exposure to NPs on subsequent uptake of other NPs have not been investigated. In the present study, we investigated the effects of pre-exposure to three NPs (TiO₂, Fe₂O₃, and SiO₂ NPs) on the subsequent uptake of gold NPs (AuNPs) by hepatocellular carcinoma cells (HepG2). When HepG2 cells were pre-exposed to TiO₂ or Fe₂O₃ NPs, but not SiO₂ NPs for 2 days, their subsequent uptake of AuNPs was inhibited. Such inhibition was also observed in human cervical cancer (HeLa) cells, suggesting that this phenomenon is present in different cell types. The mechanisms underlying the inhibitory effect of NP pre-exposure include altered plasma membrane fluidity due to changes in lipid metabolism and reduced intracellular ATP production due to decreased intracellular oxygen. Despite the inhibitory effects of NP pre-exposure, full recovery was observed after transferring the cells to medium without NPs, even when the pre-exposure time was extended from 2 days to 2 weeks. Overall, the pre-exposure effects observed in the present study should be considered in the biological application and risk evaluation of NPs.

Fortifying angiogenic efficacy of conditioned media using phototoxic-free blue light for wound healing

We used a blue organic light-emitting diode (bOLED) to increase the paracrine factors secreted from human adipose-derived stem cells (hADSCs) for producing conditioned medium (CM). Our results showed that while the bOLED irradiation promotes a mild-dose reactive oxygen generation that enhances the angiogenic paracrine secretion of hADSCs, it does not induce phototoxicity. The bOLED enhances paracrine factors via a cell-signaling mechanism involving hypoxia-inducible factor 1 alpha. This study demonstrated that the CM resulting from bOLED treatment shows improved therapeutic effects on mouse wound-healing models. This method contributes to overcoming the barriers to stem-cell therapies, including the toxicity and low yields from other methods such as nanoparticles, synthetic polymers, and even cell-derived vesicles.

Fluorescence microscopic platforms imaging mitochondrial abnormalities in neurodegenerative diseases

Neurodegenerative diseases (NDs) are progressive disorders that cause the degeneration of neurons. Mitochondrial dysfunction is a common symptom in NDs and plays a crucial role in neuronal loss. Mitochondrial abnormalities can be observed in the early stages of NDs and evolve throughout disease progression. Visualizing mitochondrial abnormalities can help understand ND progression and develop new therapeutic strategies. Fluorescence microscopy is a powerful tool for dynamically imaging mitochondria due to its high sensitivity and spatiotemporal resolution. This review discusses the relationship between mitochondrial dysfunction and ND progression, potential biomarkers for imaging dysfunctional mitochondria, advances in fluorescence microscopy for detecting organelles, the performance of fluorescence probes in visualizing ND-associated mitochondria, and the challenges and opportunities for developing new generations of fluorescence imaging platforms for monitoring mitochondria in NDs.

The Size Effect of Silver Nanoparticles on Reinforcing the Mechanical Properties of Regenerated Fibers

Regenerated silk fibroin (RSF), made from discarded silk cocoons, can be processed into regenerated silk fibers by a simple, inexpensive, and environmentally friendly wet-spinning process. However, the breaking strength and toughness of most RSF fibers are lower than those of natural silk. In this study, Ag nanoparticles (NPs) of different sizes were introduced into RSF to form RSF/AgNPs hybrid fibers by wet spinning. The effects of AgNPs of different sizes on the mechanical properties and structure of the hybrid fibers were investigated. The results demonstrated that the mechanical properties of hybrid fibers were significantly improved, especially the breaking strain, after the addition of four different sizes of AgNPs. With the reduction in AgNPs size (2-60 nm), the breaking strength and breaking strain of hybrid fibers tended to increase. The results showed that the hybrid fibers containing 2 nm AgNPs were remarkable, with excellent mechanical properties and toughness, and the breaking strain reached 138.27%, which was far greater than blank RSF fibers (15.02%) and even natural silk (about 21%). The S-FTIR and WAXD showed that, compared with the larger AgNPs, the smaller AgNPs contributed more to the formation of silk fibroin β-sheet and crystallinity, and reduced the β-crystallite size. This study is helpful to understand the relationship between the size of nanoparticles and the mechanical properties of hybrid fibers.

Gold nanoplatform for near-infrared light-activated radio-photothermal gas therapy in breast cancer

Although radiotherapy is one of the most common treatments for triple-negative breast cancer (TNBC), it frequently has unsatisfactory therapeutic outcomes due to the radiation resistance of tumor tissues. Therefore, a synergistic strategy is urgently needed to increase therapeutic responses and prolong patient survival. Herein, we constructed gold nanocages (GNCs) loaded with a hyperpyrexia-sensitive nitric oxide (NO) donor (thiolate cupferron) to integrate extrinsic radiosensitization, local photothermal therapy, and near-infrared-activated NO gas therapy. The resulting nanoplatform (GNCs@NO) showed a high photothermal conversion efficiency, which induced the death of cancer cells and facilitated rapid NO release in tumor tissues. The radiosensitizing efficacy of GNCs@NO was further demonstrated in vitro and in vivo. Importantly, the released NO reacted with the reactive oxide species induced by radiotherapy to produce more toxic reactive nitrogen species, exerting a synergistic effect to improve anticancer efficacy. Thus, GNCs@NO demonstrated excellent effects as a combination therapy with few adverse effects. Our work proposes a promising nanoplatform for the radio/photothermal/gas treatment of TNBC.

Nanomaterial-assisted theranosis of bone diseases

Bone-related diseases refer to a group of skeletal disorders that are characterized by bone and cartilage destruction. Conventional approaches can regulate bone homeostasis to a certain extent. However, these therapies are still associated with some undesirable problems. Fortunately, recent advances in nanomaterials have provided unprecedented opportunities for diagnosis and therapy of bone-related diseases. This review provides a comprehensive and up-to-date overview of current advanced theranostic nanomaterials in bone-related diseases. First, the potential utility of nanomaterials for biological imaging and biomarker detection is illustrated. Second, nanomaterials serve as therapeutic delivery platforms with special functions for bone homeostasis regulation and cellular modulation are highlighted. Finally, perspectives in this field are offered, including current key bottlenecks and future directions, which may be helpful for exploiting nanomaterials with novel properties and unique functions. This review will provide scientific guidance to enhance the development of advanced nanomaterials for the diagnosis and therapy of bone-related diseases.

Green Hydrogel Synthesis: Emphasis on Proteomics and Polymer Particle-Protein Interaction

The field of drug discovery has seen significant progress in recent years. These advances drive the development of new technologies for testing compound's effectiveness, as well as their adverse effects on organs and tissues. As an auxiliary tool for drug discovery, smart biomaterials and biopolymers produced from biodegradable monomers allow the manufacture of multifunctional polymeric devices capable of acting as biosensors, of incorporating bioactives and biomolecules, or even mimicking organs and tissues through self-association and organization between cells and biopolymers. This review discusses in detail the use of natural monomers for the synthesis of hydrogels via green routes. The physical, chemical and morphological characteristics of these polymers are described, in addition to emphasizing polymer-particle-protein interactions and their application in proteomics studies. To highlight the diversity of green synthesis methodologies and the properties of the final hydrogels, applications in the areas of drug delivery, antibody interactions, cancer therapy, imaging and biomarker analysis are also discussed, as well as the use of hydrogels for the discovery of antimicrobial and antiviral peptides with therapeutic potential.

The interaction of micro/nano plastics and the environment: Effects of ecological corona on the toxicity to aquatic organisms

Concerns about the micro/nano plastics (MNPs) exposure risks have risen in recent years. The ecological corona (EC), which is generated by the interaction between MNPs and environmental substances, has a significant impact on their environmental fate and ecological risks. As the largest sink of MNPs, the aquatic environment is of great significance for understanding the environmental behaviour of MNPs. Transmission Electron Microscope (TME), Fourier Transform Infra-Red (FTIR), Scanning Electron Microscope (SEM), Dynamic Light Scattering (DLS) and other analytical methods have been used as effective methods to analyse the formation process of EC and detect the existing EC directly or indirectly on the surface of MNPs. The physicochemical properties of MNPs, complex aquatic environments and ageing time have been identified as the key factors affecting EC formation in aquatic environments. Moreover, the EC absorbed on MNPs significantly changed their environmental behaviour and toxicity to aquatic organisms. This review gives a full understanding of the EC formation progress on the surface of MNPs and different analytical methods for EC have been summarised which can further assist the ecological risk assessment of MNPs in the aquatic environment.

Folding of Flexible Protein Fragments and Design of Nanoparticle-Based Artificial Antibody Targeting Lysozyme

It is generally believed that a protein's sequence solely determines its native structure, but how the long- and short-range interactions jointly determine the native structure/conformation of the protein or every local fragment of the protein is still not fully understood. Since most protein fragments are unstructured on their own, direct observation of the folding of flexible protein fragments is very difficult. Interestingly, we show that it is possible to graft the complementary-determining regions (CDRs) of antibodies onto the surface of a gold nanoparticle (AuNP) to create AuNP-based artificial antibodies (denoted as Goldbodies), such as an antilysozyme Goldbody. Goldbodies can specifically recognize the corresponding antigens like the original natural antibodies do, but direct structural evidence for the refolding or restoration of native conformation of the grafted CDRs on AuNPs is still missing and in high demand. Herein we design a new Goldbody that targets an epitope on the lysozyme different from that of the previous antilysozyme Goldbody, and the one circle of helix in the CDR makes it possible to distinguish the unfolded conformation of the free CDR and its folded conformation on AuNPs by circular dichroism (CD) spectroscopy. The refolding of flexible protein fragments on NPs provides unique evidence and inspiration for understanding the fundamental principles of protein folding.

The interfacial interactions of nanomaterials with human serum albumin

The fates of nanomaterials (NMs) in vivo are greatly dependent on their interactions with human serum proteins. However, the interfacial molecular details of NMs-serum proteins are still difficult to be probed. Herein, the molecular interaction details of human serum albumin (HSA) with Au and SiO₂ nanoparticles have been systematically interrogated and compared by using lysine reactivity profiling mass spectrometry (LRP-MS). We demonstrated the biocompatibility of Au is better than SiO₂ nanoparticles and the NMs surface charge state played a more important role than particle size in the combination of NMs-HSA at least in the range of 15-40 nm. Our results will contribute to the fundamental mechanism understanding of NMs-serum protein interactions as well as the NMs rational design.

Conformationally engineering flexible peptides on silver nanoparticles

Molecular conformational engineering is to engineer flexible non-functional molecules into unique conformations to create novel functions just like natural proteins fold. Obviously, it is a grand challenge with tremendous opportunities. Based on the facts that natural proteins are only marginally stable with a net stabilizing energy roughly equivalent to the energy of two hydrogen bonds, and the energy barriers for the adatom diffusion of some metals are within a similar range, we propose that metal nanoparticles can serve as a general replacement of protein scaffolds to conformationally engineer protein fragments on the surface of nanoparticles. To prove this hypothesis, herein, we successfully restore the antigen-recognizing function of the flexible peptide fragment of a natural anti-lysozyme antibody on the surface of silver nanoparticles, creating a silver nanoparticle-base artificial antibody (Silverbody). A plausible mechanism is proposed, and some general principles for conformational engineering are summarized to guide future studies in this area.

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A silver NP-based artificial antibody is created by conformational engineering

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Function emerges on NPs from non-functional peptide by mimicking the protein folding

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A general mechanism is proposed for the conformational engineering on metal NPs

Dynamic process, mechanisms, influencing factors and study methods of protein corona formation

Nanoparticles interacting with proteins to form protein corona represent one of the most fundamental problems in the rapid development of nanotechnology. In the past decade, thousands of studies have pointed out this issue. Within multi-protein systems, the formation of protein corona is a homeostasis process in which proteins compete for the limited surface sites of nanoparticles. Besides, the formation of protein corona generally shows a tendency of evolving with time and involves many different driving forces controlled by properties of nanoparticles, proteins and environment. Therefore, recent research on the dynamic process and mechanisms of protein corona formation in both animals and plants are summarized in this review. The factors that affect the formation and the techniques that commonly used for protein corona analysis are proposed. Furthermore, in order to provide reference for the future research, the limitations and challenges in protein corona studies are assessed and the future perspectives are proposed.

In vivo self-assembled drug nanocrystals for metastatic breast cancer all-stage targeted therapy

Chemotherapy is still the mainstay treatment for metastatic triple-negative breast cancers (TNBC) currently in clinical practice. The unmet needs of chemotherapy for metastatic TNBC are mainly from the insufficient drug delivery and unavailable targeting strategy that thwart the whole progression of metastatic TNBC. The in vivo ligands-mediated active targeting efficiency is usually affected by protein corona. While, the protein corona-bridged natural targeting, in turn, provides a new way for specific drug delivery. Herein, we develop a novel metastatic progression-oriented in vivo self-assembled Cabazitaxel nanocrystals (CNC) delivery system (PC/CNC) through the CNC automatically absorbing functional plasma proteins (transferrin, apolipoprotein A-IV and apolipoprotein E) in vivo, aiming to achieve the simultaneously targeted delivery to primary tumors, circulating tumor cells and metastatic lesions. With the unique advantages of superhigh drug-loading and protein corona empowered active targeting properties to tumor cells, HUVECs, active-platelets and blood-brain barrier/blood-tumor barrier, the PC/CNC exhibits a significantly improved therapeutic effect in metastatic TNBC therapy compared with free drug and CNC-loaded liposomes.

Magnetic resonance imaging of tumor-infiltrating lymphocytes by anti-CD3-conjugated iron oxide nanoparticles

Immune checkpoint blockade, considered a revolutionary approach in cancer treatment, is only effective in patients with high tumor-infiltrating lymphocytes (TILs). This work aimed to investigate the feasibility of targeted contrast agent (CA) based on dextran-coated superparamagnetic iron oxide nanoparticles (SPIONs-DEX) for TILs detection by magnetic resonance imaging (MRI) studies. To do so, we synthesized an MRI CA by conjugating SPIONs-DEX to an anti-CD3 monoclonal antibody via cyanogen bromide as a cross-linker. In vitro assessments demonstrated the higher labeling efficiency of the developed CA to CD3+ lymphocytes compared to SPIONs-DEX. In vivo MRI of a xenograft model of CD3+ lymphocytes revealed the significant signal loss after the intravenous injection of the bioconjugate by ~ 34% and 21% in T 2 * -weighted and T 2 -weighted images, respectively. The histopathological evaluation of xenograft tumors confirmed the labeling of lymphocytes by the targeted CA. This approach could open up a new horizon in the non-invasive assessment of TILs to identify patients eligible for immunotherapy.

Investigation of interaction between MXene nanosheets and human plasma and protein corona composition

The composition of protein corona affects the behavior and fate of nanoparticles in biological systems, which strongly relates to the intrinsic properties of nanoparticles and proteins. Here, three types of MXene Ti₃C₂T_x nanosheets are prepared by different etching methods, and certain physicochemical characteristics of the nanosheets before and after exposure to human plasma (HP) are characterized. The Ti₃C₂T_x nanosheets with protein coronas suffer more easily from aggregation than pristine Ti₃C₂T_x. The composition of protein coronas by LC-MS/MS-based label-free proteomic analysis reveals a high overlap of protein types and functions but a significant difference in relative protein abundance for the three Ti₃C₂T_x. Immunoglobulins and coagulation proteins are highly enriched while albumin is depleted in the coronas compared with their abundance in original HP. The random forest classification model predicts that the main driving forces for the adsorption of HP proteins on Ti₃C₂T_x are hydrogen bonding, steric hindrance, and hydrophobic interaction. This study provides insights into the colloidal stability of Ti₃C₂T_x nanosheets and their interaction with human plasma proteins.

A potential inhibitor of MDM2 by restoring the native conformation of the p53 α-helical peptide on gold nanoparticles

Many efforts have been made to develop inhibitors of MDM2 as potential drugs for cancer therapy. In this work, we use our previous developed conformational engineering technique to stabilize the binding conformation of the p53 transcription activation domain (TAD) peptide on gold NPs (AuNPs), and create an AuNP-based anti-MDM2 artificial antibody, denoted as Goldbody, that specifically binds MDM2. Though the free TAD peptide is unstructured, circular dichroism spectra confirm that its α-helical conformation in the original p53 protein is restored on the anti-MDM2 Goldbody, and surface plasmon resonance (SPR) experiments confirm that there is strong specific interaction between the anti-MDM2 Goldbody and MDM2, demonstrating the anti-MDM2 Goldbody as a potential inhibitor of MDM2. This work demonstrates that the conformational engineering technique is not limited to the antigen-antibody systems, but can also be applied more widely in other protein-protein interfaces to create more and more artificial proteins for various biomedical applications.

Temperature-Responsive Nanoparticles Enable Specific Binding of Apolipoproteins from Human Plasma

Apolipoproteins are an important class of proteins because they provide a so-called stealth effect to nanoparticles. The stealth effect on nanocarriers leads to a reduced unspecific uptake into immune cells and thereby to a prolonged blood circulation time. Herein, a novel strategy to bind apolipoproteins specifically on nanoparticles by adjusting the temperature during their incubation in human plasma is presented. This specific binding, in turn, allows a control of the stealth behavior of the nanoparticles. Nanoparticles with a well-defined poly(N-isopropylacrylamide) shell are prepared, displaying a reversible change of hydrophobicity at a temperature around 32 °C. It is shown by label-free quantitative liquid chromatography-mass spectrometry that the nanoparticles are largely enriched with apolipoprotein J (clusterin) at 25 °C while they are enriched with apolipoprotein A1 and apolipoprotein E at 37 °C. The temperature-dependent protein binding is found to significantly influence the uptake of the nanoparticles by RAW264.7 and HeLa cells. The findings imply that the functionalization of nanoparticles with temperature-responsive materials is a suitable method for imparting stealth properties to nanocarriers for drug-delivery.

PEGylation of Goldbody: PEG-aided conformational engineering of peptides on gold nanoparticles

It is still a great challenge to engineer flexible non-functional molecules into special conformations to carry out novel functions. Previously, we successfully restored the native conformations and functions of the flexible complementary-determining regions (CDRs) of antibodies on the surface of gold nanoparticles (AuNPs), and created a class of AuNP-based artificial antibodies, denoted as Goldbodies. Yet, in these Goldbodies, there are dozens of CDRs on one Goldbody. Herein, we show that the number of CDRs per Goldbody could be reduced by more than one order of magnitude, by replacing the majority of the CDRs with polyethylene glycol (PEG) with a molecular weight around 600 Da, while the native conformations and functions of the CDRs could still be restored on AuNPs. Also, we find that the PEG with two terminal –SH groups is much better than the PEG with a single –SH group for aiding the restoration of the native conformation of the CDRs on AuNPs. To demonstrate the potential generic applicability of the PEGylation in aiding conformational engineering of peptides, two PEGylated Goldbodies have been created, which can specifically recognize lysozyme and epidermal growth factor receptor, respectively. The PEGylated Goldbodies further prove the mechanism of conformational engineering and the “Confined Lowest Energy Fragments” (CLEFs) hypothesis, and pave the way for future applications of Goldbodies.

PEG with two terminal –SH groups can help to restore the native conformation of CDRs when PEG and CDRs are conjugated onto AuNPs together, thus creating the PEGylated Goldbody.

Formation and biological effects of protein corona for food-related nanoparticles

The rapid development of nanoscience and nanoengineering provides new perspectives on the composition of food materials, and has great potential for food biology research and applications. The use of nanoparticle additives and the discovery of endogenous nanoparticles in food make it important to elucidate in vivo safety of nanomaterials. Nanoparticles will spontaneously adsorb proteins during transporting in blood and a protein corona can be formed on the nanoparticle surface inside the human body. Protein corona affects the physicochemical properties of nanoparticles and the structure and function of proteins, which in turn affects a series of biological reactions. This article reviewed basic information about protein corona of food-related nanoparticles, elucidated the influence of protein corona on nanoparticles properties and protein structure and function, and discussed the effect of protein corona on nanoparticles in vivo. The effects of protein corona on nanoparticles transport, cellular uptake, cytotoxicity, and immune response were reviewed, and the reasons for these effects were also discussed. Finally, future research perspectives for food protein corona were proposed. Protein corona gives food nanoparticles a new identity, which makes proteins bound to nanoparticles undergo structural transformations that affect their recognition by receptors in vivo. It can have positive or negative impacts on cellular uptake and toxicity of nanoparticles and even trigger immune responses. Understanding the effects of protein corona have potential in evaluating the fate of the food-related nanoparticles, providing physicochemical and biological information about the interaction between proteins and foodborne nanoparticles. The review article will help to evaluate the safety of protein coronas formed on nanoparticles in food, and may provide fundamental information for understanding and controlling nanotoxicity.

Quantitative Measurement of Multiprotein Nanoparticle Interactions Using NMR Spectroscopy

An effective intensity-based reference is a cornerstone for quantitative nuclear magnetic resonance (NMR) studies, as the molecular concentration is encoded in its signal. In theory, NMR is well suited for the measurement of competitive protein adsorption onto nanoparticle (NP) surfaces, but current referencing systems are not optimized for multidimensional experiments. Presented herein is a simple and novel referencing system using ¹⁵N tryptophan (Trp) as an external reference for ¹H-¹⁵N 2D NMR experiments. The referencing system is validated by the determination of the binding capacity of a single protein onto gold NPs. Then, the Trp reference is applied to protein mixtures, and signals from each protein are accurately quantified. All results are consistent with previous studies, but with substantially higher precision, indicating that the Trp reference can accurately calibrate the residue peak intensities and reduce systematic errors. Finally, the proposed Trp reference is used to kinetically monitor in situ and in real time the competitive adsorption of different proteins. As a challenging test case, we successfully apply our approach to a mixture of protein variants differing by only a single residue. Our results show that the binding of one protein will affect the binding of the other, leading to an altered NP corona composition. This work therefore highlights the importance of studying protein-NP interactions in protein mixtures in situ, and the referencing system developed here enables the quantification of binding kinetics and thermodynamics of multiple proteins using various ¹H-¹⁵N 2D NMR techniques.

Protein Adsorption onto Modified Porous Silica by Single and Binary Human Serum Protein Solutions

Typical porous silica (SBA-15) has been modified with pore expander agent (1,3,5-trimethylbenzene) and fluoride-species to diminish the length of the channels to obtain materials with different textural properties, varying the Si/Zr molar ratio between 20 and 5. These porous materials were characterized by X-ray Diffraction (XRD), N2 adsorption/desorption isotherms at -196 °C and X-ray Photoelectron Spectroscopy (XPS), obtaining adsorbent with a surface area between 420-337 m2 g-1 and an average pore diameter with a maximum between 20-25 nm. These materials were studied in the adsorption of human blood serum proteins (human serum albumin-HSA and immunoglobulin G-IgG). Generally, the incorporation of small proportions was favorable for proteins adsorption. The adsorption data revealed that the maximum adsorption capacity was reached close to the pI. The batch purification experiments in binary human serum solutions showed that Si sample has considerable adsorption for IgG while HSA adsorption is relatively low, so it is possible its separation.

Solution NMR of Nanoparticles in Serum: Protein Competition Influences Binding Thermodynamics and Kinetics

The spontaneous formation of a protein corona on a nanoparticle surface influences the physiological success or failure of the synthetic nanoparticle as a drug carrier or imaging agent used in vivo. A quantitative understanding of protein-nanoparticle interactions is therefore critical for the development of nanoparticle-based therapeutics. In this perspective, we briefly discuss the challenges and limitations of current approaches used for studying protein-nanoparticle binding in a realistic biological medium. Subsequently, we demonstrate that solution nuclear magnetic resonance (NMR) spectroscopy is a powerful tool to monitor protein competitive binding in a complex serum medium in situ. Importantly, when many serum proteins are competing for a gold nanoparticle (AuNP) surface, solution NMR is able to detect differences in binding thermodynamics, and kinetics of a tagged protein. Combined with other experimental approaches, solution NMR is an invaluable tool to understand protein behavior in the nanoparticle corona.

Interaction of nanoplastics with extracellular polymeric substances (EPS) in the aquatic environment: A special reference to eco-corona formation and associated impacts

Nanoplastics (NPs) are plastic particles with sizes ranging between 1 and 1000 nm, exhibiting exceptional qualities such as large surface area, lightweight, durability; therefore, are widely used in cosmetics, paints, electronics, etc. NPs are inevitability released into the aquatic environment where they tend to interact with both, the extracellular polymeric substances (EPS) and other fractions of natural organic matter (NOM), respectively secreted by organisms (e.g., DNA, proteins, and carbohydrates) and degradation byproducts of organic materials (e.g., humic acid and fulvic acid) fluxed into the water bodies. These biomolecules robustly encapsulate NPs to develop an eco-corona layer that alters not only the physicochemical properties but also the fate, bioreactivity, and ecological impacts of NPs. Therefore, this review summarized the documented studies highlighting the eco-corona formation on NPs and associated ecological implications in the aquatic environment. After presenting the precise background information on the occurrence of NPs and EPS in the aquatic environment, we demonstrated the basic difference between eco-corona and bio-corona formation. The reviewed studies showed that the eco-corona formed on NPs have varying sizes and composition, mainly depending on the properties of parent biomolecules, characteristics of NPs, and physicochemical parameters of the aquatic environment. Further, the potential methods for characterization and quantification of eco-corona and its composition have been also highlighted. Moreover, the ecological implications (both toxic and non-toxic) of eco-corona formation on NPs in marine and freshwater environments have been also summarized. Last but not the least, challenges and future research directions are also given, e.g., conducting field studies on eco-corona formation in the aquatic environment, optimizing methods for its characterization and quantification, and considering eco-corona concept in the future toxicity studies on NPs. Finally, understanding eco-corona formation will be critical to unveil the complex NP interactions occurring in natural aquatic systems.

Characterization of blood protein adsorption on PM2.5 and its implications on cellular uptake and cytotoxicity of PM2.5

In biological fluids, micro- or nano-size particles are prone to adsorb proteins and form a layer. The ambient air fine particulate matter (PM_2.5) is inhaled via the lung, penetrates biological barriers and eventually reaches systemic blood circulation. However, there are very few data available regarding the adsorption of proteins on PM_2.5. Here, we compared protein corona formed in plasma after bronchoalveolar lavage fluid (BALF) exposure with those formed in plasma alone. Using purified coronal proteins, we explored their adsorption behaviors on PM_2.5 and their influence on biological reactivity of PM_2.5. Liquid-chromatography tandem mass-spectrometry (LC-MS/MS) analysis revealed that exposure to BALF significantly changed the blood protein profile on PM_2.5. Regardless of the presence of BALF, the protein corona on PM_2.5 contained an abundance of serum albumin, hemoglobin (Hb) and fibrinogen (Fg) proteins. Using Fg as a corona surrogate, we found that van der Waals interactions, hydrophobic interactions, π-π stacking and electrostatic attractions contributed to the Fg adsorption and led to the conformational changes of Fg. In addition, Fg decoration decreased cellular internalization of PM_2.5 and corresponding subsequent oxidative stress responses in a murine RAW264.7 macrophage. These results support the view that the formation of PM_2.5 corona should be considered for toxicity assessment of PM_2.5.

Magnetic nanoparticles for cancer theranostics: Advances and prospects

Cancer is one of the leading causes of mortality worldwide. Nanoparticles have been broadly studied and emerged as a novel approach in diagnosis and treatment of tumors. Over the last decade, researches have significantly improved magnetic nanoparticle (MNP)'s theranostic potential as nanomedicine for cancer. Newer MNPs have various advantages such as wider operating temperatures, smaller sizes, lower toxicity, simpler preparations and lower production costs. With a series of unique and superior physical and chemical properties, MNPs have great potential in medical applications. In particular, using MNPs as probes for medical imaging and carriers for targeted drug delivery systems. While MNPs are expected to be the future of cancer diagnosis and precision drug delivery, more research is still required to minimize their toxicity and improve their efficacy. An ideal MNP for clinical applications should be precisely engineered to be stable to act as tracers or deliver drugs to the targeted sites, release drug components only at the targeted sites and have minimal health risks. Our review aims to consolidate the recent improvements in MNPs for clinical applications as well as discuss the future research prospects and potential of MNPs in cancer theranostics.

Molybdenum derived from nanomaterials incorporates into molybdenum enzymes and affects their activities in vivo

Many nanoscale biomaterials fail to reach the clinical trial stage due to a poor understanding of the fundamental principles of their in vivo behaviour. Here we describe the transport, transformation and bioavailability of MoS2 nanomaterials through a combination of in vivo experiments and molecular dynamics simulations. We show that after intravenous injection molybdenum is significantly enriched in liver sinusoid and splenic red pulp. This biodistribution is mediated by protein coronas that spontaneously form in the blood, principally with apolipoprotein E. The biotransformation of MoS2 leads to incorporation of molybdenum into molybdenum enzymes, which increases their specific activities in the liver, affecting its metabolism. Our findings reveal that nanomaterials undergo a protein corona-bridged transport-transformation-bioavailability chain in vivo, and suggest that nanomaterials consisting of essential trace elements may be converted into active biological molecules that organisms can exploit. Our results also indicate that the long-term biotransformation of nanomaterials may have an impact on liver metabolism.

Enhanced wound repair ability of arginine-chitosan nanocomposite membrane through the antimicrobial peptides-loaded polydopamine-modified graphene oxide

Skin wound healing is a complicated and lengthy process, which is influenced by multiple factors and need a suitable cellular micro-environment. For skin wound, wound dressings remain a cornerstone of dermatologic therapy at present. The dressing material can create an effective protective environment for the wound, and the interactions between the dressing and the wound has a great impact on the wound healing efficiency. An ideal wound dressing materials should have good biocompatibility, moisturizing property, antibacterial property and mechanical strength, and can effectively prevent wound infection and promote wound healing. In this study, in order to design wound dressing materials endowed with excellent antibacterial and tissue repair properties, we attempted to load antimicrobial peptides onto dopmine-modified graphene oxide (PDA@GO) using lysozyme (ly) as a model drug. Then, functionalized GO was used to the surface modification of arginine-modified chitosan (CS-Arg) membrane. To evaluate the potential of the prepared nanocomposite membrane in wound dressing application, the surface morphology, hydrophilic, mechanical properties, antimicrobial activity, and cytocompatibility of the resulting nanocomposite membrane were analyzed. The results revealed that prepared nanocomposite membrane exhibited excellent hydrophilic, mechanical strength and antimicrobial activity, which can effectively promote cell growth and adhesion. In particular, using PDA@GO as drug carrier can effectively maintain the activity of antimicrobial peptides, and can maximize the antibacterial properties of the nanocomposite membrane. Finally, we used rat full-thickness wound models to observe wound healing, and the surface interactions between the prepared nanocomposite membrane and the wound. The results indicated that nanocomposite membrane can obviously accelerated wound closure, and the wounds showed reduced inflammation, improved angiogenesis and accelerated re-epithelialization. Therefore, incorporation of antimicrobial peptides-functionalize graphene oxide (ly-PDA@GO) into CS-Arg membrane was a viable strategy for fabricating excellent wound dressing. Together, this study not only prepared a wound dressing with excellent tissue repair ability, but also provided a novel idea for the development of graphene oxide-based antibacterial dressing.

Research progress and application opportunities of nanoparticle-protein corona complexes

Nanoparticles (NPs) can be used to design for nanomedicines with different chemical surface properties owing to their size advantages and the capacity of specific delivery to targeted sites in organisms. The discovery of the presence of protein corona (PC) has changed our classical view of NPs, stimulating researchers to investigate the in vivo fate of NPs as they enter biological systems. Both NPs and PC have their specificity but complement each other, so they should be considered as a whole. The formation and characterization of NP-PC complexes provide new insights into the design, functionalization, and application of nanocarriers. Based on progress of recent researches, we reviewed the formation, characterization, and composition of the PC, and introduced those critical factors influencing PC, simultaneously expound the effect of PC on the biological function of NPs. Especially we put forward the opportunities and challenges when NP-PC as a novel nano-drug carrier for targeted applications. Furthermore, we discussed the pros versus cons of the PC, as well as how to make better PC in the future application of NPs.

Nano-bio interface between human plasma and niosomes with different formulations indicates protein corona patterns for nanoparticle cell targeting and uptake

Unraveling the proteins interacting with nanoparticles (NPs) in biological fluids, such as blood, is pivotal to rationally design NPs for drug delivery. The protein corona (PrC), formed on the NP surface, represents an interface between biological components and NPs, dictating their pharmacokinetics and biodistribution. PrC composition depends on biological environments around NPs and on their intrinsic physicochemical properties. We generated different formulations of non-ionic surfactant/non-phospholipid vesicles, called niosomes (NIOs), using polysorbates which are biologically safe, cheap, non-toxic and scarcely immunogenic. PrC composition and relative protein abundance for all designed NIOs were evaluated ex vivo in human plasma (HP) by quantitative label-free proteomics. We studied the correlation of the relative protein abundance in the corona with cellular uptake of the PrC-NIOs in healthy and cancer human cell lines. Our results highlight the effects of polysorbates on nano-bio interactions to identify a protein pattern most properly aimed to drive the NIO targeting in vivo, and assess the best conditions of PrC-NIO NP uptake into the cells. This study dissected the biological identity in HP of polysorbate-NIOs, thus contributing to shorten their passage from preclinical to clinical studies and to lay the foundations for a personalized PrC.

Evidence of protein coronas around soft nanoparticles regardless of the chemical nature of the outer surface: structural features and biological consequences

The formation of biomolecular coronas around nanoparticles as soon as they come in contact with biological media is nowadays well accepted. The self-developed biological outer surfaces can affect the targeting capability of the colloidal carriers as well as their cytotoxicity and cellular uptake behavior. In this framework, we explored the structural features and biological consequences of protein coronas around block copolymer assemblies consisting of a common pH-responsive core made by poly[2-(diisopropylamino) ethyl methacrylate] (PDPA) and hydrophilic shells of different chemical natures: zwitterionic poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) or highly hydrophilic poly(ethylene oxide) (PEO) and poly(N-(2-hydroxypropyl)methacrylamide) (PHPMA). We demonstrated the presence of ∼50 nm protein coronas around the nanoparticles regardless of the chemical nature of the polymeric shells. The thickness is understood as the sum of the soft and hard layers and it is the actual interface seen by the cells. Although the soft corona composition is difficult to determine because the proteins are loosely bound to the outer surface of the assemblies, the tightly bound proteins (hard corona) could be identified and quantified. The compositional analysis of the hard corona demonstrated that human serum albumin (HSA), immunoglobulin G (IgG) and fibrinogen are the main components of the protein coronas, and serotransferrin is present particularly in the protein corona of the zwitterionic-stabilized assemblies. The protein coronas substantially reduce the cellular uptake of the colloidal particles due to their increased size and the presence of HSA which is known to reduce nanoparticle-cell adhesion. On the other hand, their existence also reduces the levels of cytotoxicity of the polymeric assemblies, highlighting that protein coronas should not be always understood as artifacts that need to be eliminated due to their positive outputs.

Advanced nanomedicine and cancer: Challenges and opportunities in clinical translation

Cancer has reached pandemic dimensions in the whole world. Although current medicine offers multiple treatment options against cancer, novel therapeutic strategies are needed due to the low specificity of chemotherapeutic drugs, undesired side effects and the presence of different incurable types of cancer. Among these new strategies, nanomedicine arises as an encouraging approach towards personalized medicine with high potential for present and future cancer patients. Therefore, nanomedicine aims to develop novel tools with wide potential in cancer treatment, imaging or even theranostic purposes. Even though numerous preclinical studies have been published with successful preliminary results, promising nanosystems have to face multiple obstacles before adoption in clinical practice as safe options for patients with cancer. In this MiniReview, we provide a short overview on the latest advances in current nanomedicine approaches, challenges and promising strategies towards more accurate cancer treatment.