Crossing Biological Barriers by Engineered Nanoparticles

Hyaluronic Acid-Based Nanomotors: Crossing Mucosal Barriers to Tackle Antimicrobial Resistance

Bacterial infections pose a significant global health challenge aggravated by the rise of antimicrobial resistance (AMR). Among the obstacles preventing effective treatment are biological barriers (BBs) within the body such as the mucus layer. These BBs trap antimicrobials, necessitating higher doses and ultimately accelerating AMR. Addressing this issue requires innovative therapeutic strategies capable of bypassing BBs to deliver drugs more effectively. Here, we present nanomotors (NMs) based on hyaluronic acid (HA)- and urease-nanogels (NGs) as a solution to navigate effectively in viscous media by catalyzing the decomposition of urea into ammonium and carbon dioxide. These HA-based nanomotors (HA-NMs) were loaded with chloramphenicol (CHL) antibiotic and demonstrated superior antimicrobial activity against Escherichia coli(E. coli) compared to mesoporous silica NMs (MSNP-NMs), a reference in the field of NMs. Moreover, using an in vitro transwell model we evaluated the ability of HA-NMs to penetrate mucin barriers, effectively reducing E. coli proliferation, whereas the free antibiotic did not reduce bacteria proliferation. The optical density reduction at 24 h was over ten times greater than with free CHL. These organic-based enzyme-powered NMs represent a significant advancement in drug delivery, offering a promising approach to combat AMR while addressing the challenges of crossing complex BBs.

TiO2 P25 Nanoparticles Induce Mitochondrial damage and Increased Glutathione Synthesis in SH-SY5Y Neural Cells

The increasing occurrence of TiO2 nanoparticles in the environment leads to a higher risk of their entry into the human body. Because the nanomaterials can cross the blood-brain barrier, the knowledge of their effect in neural cells is also crucial. However, the exact mechanism of toxicity remains unclear. Therefore, our objective was to evaluate the biological effect of TiO2 nanoparticles in neural cells. Therefore, we aimed to evaluate the biological effect of TiO2 nanoparticles in neural cells. We used neuroblastoma SH-SY5Y cells treated with 25 nm TiO2 nanoparticles (TiO2 P25; 1-100 μg·mL-1; 24-72 h). We measured dehydrogenase activity, glutathione metabolism, DNA damage and mitochondrial respiration. After treatment of SH-SY5Y cells with TiO2 P25, we found a dose- and time-dependent decrease in dehydrogenase activity together with nuclear changes. Interestingly, 100 μg·mL-1 TiO2 P25 caused a significant increase of glutathione levels (p < 0.001) linked with increased glutamate-cysteine ligase expression after both 24 and 48 h. Furthermore, as the first study at all, we observed the significant decreases of mitochondrial respiration in SH-SY5Y cells caused by treatments with 10 and 100 μg·mL-1 TiO2 P25 after 48 and 72 h. In conclusion, our study brings new finding of occurrence of decreased mitochondrial respiration without glutathione depletion in SH-SY5Y cells contributing to the understanding of TiO2 P25 toxicity in neural cells.

Nanoparticle-Mediated Embryotoxicity: Mechanisms of Chemical Toxicity and Implications for Biological Development

Nanoparticles, defined by their nanoscale dimensions and unique physicochemical properties, are widely utilized in healthcare, electronics, environmental sciences, and consumer products. However, increasing evidence of their potential embryotoxic effects during pregnancy underscores the need for a molecular-level understanding of their interactions during embryonic development. Nanoparticles such as titanium dioxide, silver, cerium oxide, copper oxide, and quantum dots can cross the placental barrier and interfere with crucial developmental processes. At the molecular level, they disrupt signaling pathways like Wnt and Hedgehog, induce oxidative stress and inflammation, and cause genotoxic effects, all critical during sensitive phases, such as organogenesis. Furthermore, these nanoparticles interact directly with cellular components, including DNA, proteins, and lipids, impairing cellular function and viability. Innovative strategies to mitigate nanoparticle toxicity, such as surface modifications and incorporation of biocompatible coatings, are discussed as potential solutions to reduce adverse molecular interactions. Various laboratory animal models used to investigate nanoparticle-induced embryotoxicity are evaluated for their efficacy and limitations, providing insights into their applicability for understanding these effects. This Account examines the molecular mechanisms by which nanoparticles compromise embryonic development and emphasizes the importance of designing safer nanoparticles to minimize maternal-fetal exposure risks, particularly in biomedical applications.

Micro- and Nanomotors: Engineered Tools for Targeted and Efficient Biomedicine

Over the past two decades, nanotechnology has made significant progress toward the development and applications of micromotors (MMs) and nanomotors (NMs). Characterized by their capability to self-propel and swim in fluids, they have emerged as promising tools in various fields, particularly in biomedicine. This Review presents an overview of the current state of MMs and NMs, their motion in viscous media and complex environments, their interaction with biological barriers, and potential therapeutical applications. We identify the choice of appropriate administration routes to reach their target location as a key aspect of the success of MMs and NMs in biomedical applications. Looking ahead, we envision NMs playing a key role in treating diverse medical disorders, as recent proof-of-concept in vivo studies demonstrate their distinct capabilities and versatility. However, addressing regulatory, scalability, biocompatibility, and safety concerns remains imperative for the successful translation of NMs into clinical trials and industrial-scale production. This work provides a guideline for researchers, guiding them through the current landscape, challenges, and prospects of using MMs and NMs in biomedicine, thereby encouraging their responsible development and positioning in the future of nanomedicine. Furthermore, we outline critical areas for further research, including studies on biocompatibility, safety, and methods to overcome physical obstacles.

The piper at the gates of brain: A systematic review of surface modification strategies on lipid nanoparticles to overcome the Blood-Brain-Barrier

The Blood-Brain Barrier (BBB) significantly impedes drug delivery to the central nervous system. Nanotechnology, especially surface-functionalized lipid nanoparticles, offers innovative approaches to overcome this barrier. However, choosing an effective functionalization strategy is challenging due to the lack of detailed comparative analysis in current literature. Our systematic review examined various functionalization strategies and their impact on BBB permeability from 2041 identified articles, of which 80 were included for data extraction. Peptides were the most common modification (18) followed by mixed strategies (12) proteins (9), antibodies (7), and other strategies (8). Interestingly, 26 studies showed BBB penetration with unmodified or modified nanoparticles using commonly applied strategies such as PEGylation or surfactant addition. Statistical analysis across 42 studies showed correlation between higher in vivo permeation improvements and nanoparticle type, size, and functionalization category. The highest ratios were found for nanostructured lipid carriers or biomimetic systems, in studies with particle sizes under 150 nm, and in those applying mixed functionalization strategies. The interstudy heterogeneity we observed highlights the importance of adopting standardized evaluation protocols to enhance comparability. Our systematic review aims to provide a comparative insight and identify future research directions in the development of more effective lipid nanoparticle systems for drug delivery to the brain to help improve the treatment of neurological and psychiatric disorders and brain tumours.

Nanotechnology in healthcare, and its safety and environmental risks

Nanotechnology holds immense promise in revolutionising healthcare, offering unprecedented opportunities in diagnostics, drug delivery, cancer therapy, and combating infectious diseases. This review explores the multifaceted landscape of nanotechnology in healthcare while addressing the critical aspects of safety and environmental risks associated with its widespread application. Beginning with an introduction to the integration of nanotechnology in healthcare, we first delved into its categorisation and various materials employed, setting the stage for a comprehensive understanding of its potential. We then proceeded to elucidate the diverse healthcare applications of nanotechnology, spanning medical diagnostics, tissue engineering, targeted drug delivery, gene delivery, cancer therapy, and the development of antimicrobial agents. The discussion extended to the current situation surrounding the clinical translation and commercialisation of these cutting-edge technologies, focusing on the nanotechnology-based healthcare products that have been approved globally to date. We also discussed the safety considerations of nanomaterials, both in terms of human health and environmental impact. We presented the in vivo health risks associated with nanomaterial exposure, in relation with transport mechanisms, oxidative stress, and physical interactions. Moreover, we highlighted the environmental risks, acknowledging the potential implications on ecosystems and biodiversity. Lastly, we strived to offer insights into the current regulatory landscape governing nanotechnology in healthcare across different regions globally. By synthesising these diverse perspectives, we underscore the imperative of balancing innovation with safety and environmental stewardship, while charting a path forward for the responsible integration of nanotechnology in healthcare.

Design and optimization of chitosan-coated solid lipid nanoparticles containing insulin for improved intestinal permeability using piperine

The objective of this research was to optimize the composition and performance of chitosan-coated solid lipid nanoparticles carrying insulin (Ch-In-SLNs) and to assess the potential of piperine in enhancing the intestinal permeability of insulin from these SLNs in vitro. The SLNs were formulated from glyceryl behenate (GB), soya lecithin, and poloxamer® 407, and then coated with a combination of chitosan and piperine to facilitate insulin penetration across the gastrointestinal (GI) mucosa. A Box-Behnken Design (BBD) was utilized to optimize the Ch-In-SLNs formulations, with PDI, particle size, zeta potential, and association efficiency (AE) serving as the response variables. The resulting Ch-In-SLNs exhibited excellent monodispersity (PDI = 0.4), optimal particle size (654.43 nm), positive zeta potential (+36.87 mV), and low AE values. The Ch-In-SLNs demonstrated sustained release of insulin for 12 h in simulated gastric fluid (SGF) and intestinal fluid (SIF), with increased release in the latter. After incubation in SGF and SIF for 12 h, the insulin SLNs retained 54 and 41 % of their initial insulin load, respectively, indicating effective protection from gastric enzymes. Permeation studies using goat intestine and Caco-2 cell lines indicated improved insulin permeation in the presence of piperine. Additionally, cell uptake studies confirmed the role of piperine in enhancing insulin permeation.

Understanding Human Health Impacts Following Microplastic Exposure Necessitates Standardized Protocols

Microplastics (MPs; 1 µm to 5 mm) are a persistent and pervasive environmental pollutant of emergent and increasing concern. Human exposure to MPs through food, water, and air has been documented and thus motivates the need for a better understanding of the biological implications of MP exposure. These impacts are dependent on the properties of MPs, including size, morphology, and chemistry, as well as the dose and route of exposure. This overview offers a perspective on the current methods used to assess the bioactivity of MPs. First, we discuss methods associated with MP bioactivity research with an emphasis on the variety of assays, exposure conditions, and reference MP particles that have been used. Next, we review the challenges presented by common instrumentation and laboratory materials, the lack of standardized reference materials, and the limited understanding of MP dosimetry. Finally, we propose solutions that can help increase the applicability and impact of future studies while reducing redundancy in the field. The excellent protocols published in this issue are intended to contribute toward standardizing the field so that the MP knowledge base grows from a reliable foundation. © 2024 Wiley Periodicals LLC.

Fetus Exposure to Drugs and Chemicals: A Holistic Overview on the Assessment of Their Transport and Metabolism across the Human Placental Barrier

BACKGROUND

The placenta exerts a crucial role in fetus growth and development during gestation, protecting the fetus from maternal drugs and chemical exposure. However, diverse drugs and chemicals (xenobiotics) can penetrate the maternal placental barrier, leading to deleterious, adverse effects concerning fetus health. Moreover, placental enzymes can metabolize drugs and chemicals into more toxic compounds for the fetus. Thus, evaluating the molecular mechanisms through which drugs and chemicals transfer and undergo metabolism across the placental barrier is of vital importance. In this aspect, this comprehensive literature review aims to provide a holistic approach by critically summarizing and scrutinizing the potential molecular processes and mechanisms governing drugs and chemical transfer and metabolism across the placental barrier, which may lead to fetotoxicity effects, as well as analyzing the currently available experimental methodologies used to assess xenobiotics placental transfer and metabolism.

METHODS

A comprehensive and in-depth literature review was conducted in the most accurate scientific databases such as PubMed, Scopus, and Web of Science by using relevant and effective keywords related to xenobiotic placental transfer and metabolism, retrieving 8830 published articles until 5 February 2024. After applying several strict exclusion and inclusion criteria, a final number of 148 relevant published articles were included.

RESULTS

During pregnancy, several drugs and chemicals can be transferred from the mother to the fetus across the placental barrier by either passive diffusion or through placental transporters, resulting in fetus exposure and potential fetotoxicity effects. Some drugs and chemicals also appear to be metabolized across the placental barrier, leading to more toxic products for both the mother and the fetus. At present, there is increasing research development of diverse experimental methodologies to determine the potential molecular processes and mechanisms of drug and chemical placental transfer and metabolism. All the currently available methodologies have specific strengths and limitations, highlighting the strong demand to utilize an efficient combination of them to obtain reliable evidence concerning drug and chemical transfer and metabolism across the placental barrier. To derive the most consistent and safe evidence, in vitro studies, ex vivo perfusion methods, and in vivo animal and human studies can be applied together with the final aim to minimize potential fetotoxicity effects.

CONCLUSIONS

Research is being increasingly carried out to obtain an accurate and safe evaluation of drug and chemical transport and metabolism across the placental barrier, applying a combination of advanced techniques to avoid potential fetotoxic effects. The improvement of the currently available techniques and the development of novel experimental protocols and methodologies are of major importance to protect both the mother and the fetus from xenobiotic exposure, as well as to minimize potential fetotoxicity effects.

Effects of superparamagnetic iron oxide nanoparticles (SPIONS) testicular injection on Leydig cell function and sperm production in a murine model

In the domain of medical advancement, nanotechnology plays a pivotal role, especially in the synthesis of biocompatible materials for therapeutic use. Superparamagnetic Iron Oxide Nanoparticles (SPIONs), known for their magnetic properties and low toxicity, stand at the forefront of this innovation. This study explored the reproductive toxicological effects of Sodium Citrate-functionalized SPIONs (Cit_SPIONs) in adult male mice, an area of research that holds significant potential yet remains largely unknown. Our findings reveal that Cit_SPIONs induce notable morphological changes in interstitial cells and the seminiferous epithelium when introduced via intratesticular injection. This observation is critical in understanding the interactions of nanomaterials within reproductive biological systems. A striking feature of this study is the rapid localization of Cit_SPIONs in Leydig cells post-injection, a factor that appears to be closely linked with the observed decrease in steroidogenic activity and testosterone levels. This data suggests a possible application in developing nanostructured therapies targeting androgen-related processes. Over 56 days, these nanoparticles exhibited remarkable biological distribution in testis parenchyma, infiltrating various cells within the tubular and intertubular compartments. While the duration of spermatogenesis remained unchanged, there were many Tunel-positive germ cells, a notable reduction in daily sperm production, and reduced progressive sperm motility in the treated group. These insights not only shed light on the intricate mechanisms of Cit_SPIONs interaction with the male reproductive system but also highlight the potential of nanotechnology in developing advanced biomedical applications.

Microfluidic-assisted formulation of cell membrane-camouflaged anisotropic nanostructures

Anisotropic gold (Au) nanostructures have been widely explored for various nanomedicine applications. While these nanomaterials have shown great promise for disease theranostics, particularly for cancer diagnosis and treatment, the utilization and clinical translation of anisotropic Au nanostructures have been limited by their high phagocytic uptake and clearance and low cancer targeting specificity. Numerous efforts have thus been made toward mitigating these challenges. Many conventional strategies, however, rely on all-synthetic materials, involve complex chemical processes, or have low product throughput and reproducibility. Herein, by integrating cell membrane coating and microfluidic technologies, a high-throughput bioinspired approach for synthesizing biomimetic anisotropic Au nanostructures with minimized phagocytic uptake and improved cancer cell targeting is reported. Through continuous hydrodynamic flow focusing, mixing, and sonication, Au nanostructures are encapsulated within the macrophage and cancer cell membrane vesicles effectively. The fabricated nanostructures are uniform and highly stable in serum. Importantly, the macrophage membrane vesicle-encapsulated Au nanostructures can be preferentially internalized by breast cancer cells, but not by macrophages. Overall, this study has demonstrated the feasibility of employing an integrated microfluidic-sonication technique to formulate uniform and highly stable biomimetic anisotropic nanostructures for enhanced cancer theranostic applications.

Efficacy tumor therapeutic applications of stimuli-responsive block copolymer-based nano-assemblies

Block copolymers are composed of two or more blocks or segments with different chemical properties via various chemical bonds, which can assemble into nanoparticles with a "core-shell" structure. Due to the benefits of simple functionalization, superior drug-loading capacity, and good biocompatibility, various nano-assemblies based on block copolymers have become widely applied in the treatment of cancers in recent years. These nano-assemblies serve as carriers for anti-tumor bioactive, enhancing drug stability and prolonging their circulation time in vivo, which can reduce the toxic side effects of drugs and improve the therapeutic effect. However, the complex and heterogeneous tumor microenvironment poses challenges to the therapeutic efficacy of these nano-assemblies, having the result in the occurrence of drug resistance and the recurrence of tumors. Consequently, a diverse array of stimuli-responsive nano-assemblies has been devised in order to surmount these obstacles. This article provides a comprehensive overview of the utilization of stimuli-responsive nano-assemblies derived from block copolymers in the context of tumor treatment. The review summarizes block polymers responsive to internal stimuli (like ROS, redox, pH, and enzymes) and external stimuli (like light, and temperature), and discusses current challenges and prospects in this field, aiming to provide novel insights for clinical applications.

Dispersion and Dosimetric Challenges of Hydrophobic Carbon-Based Nanoparticles in In Vitro Cellular Studies

Methodologies across the dispersion preparation, characterization, and cellular dosimetry of hydrophilic nanoparticles (NPs) have been developed and used extensively in the field of nanotoxicology. However, hydrophobic NPs pose a challenge for dispersion in aqueous culture media using conventional methods that include sonication followed by mixing in the culture medium of interest and cellular dosimetry. In this study, a robust methodology for the preparation of stable dispersions of hydrophobic NPs for cellular studies is developed by introducing continuous energy over time via stirring in the culture medium followed by dispersion characterization and cellular dosimetry. The stirring energy and the presence of proteins in the culture medium result in the formation of a protein corona around the NPs, stabilizing their dispersion, which can be used for in vitro cellular studies. The identification of the optimal stirring time is crucial for achieving dispersion and stability. This is assessed through a comprehensive stability testing protocol employing dynamic light scattering to evaluate the particle size distribution stability and polydispersity. Additionally, the effective density of the NPs is obtained for the stable NP dispersions using the volumetric centrifugation method, while cellular dosimetry calculations are done using available cellular computational modeling, mirroring approaches used for hydrophilic NPs. The robustness of the proposed dispersion approach is showcased using a highly hydrophobic NP model (black carbon NPs) and two culture media, RPMI medium and SABM, that are widely used in cellular studies. The proposed approach for the dispersion of hydrophobic NPs results in stable dispersions in both culture media used here. The NP effective density of 1.03-1.07 g/cm3 measured here for black carbon NPs is close to the culture media density, resulting in slow deposition on the cells over time. So, the present methodology for dispersion and dosimetry of hydrophobic NPs is essential for the design of dose-response studies and overcoming the challenges imposed by slow particle deposition.

Cytotoxicity and Inflammatory Effects of Chitin Nanofibrils Isolated from Fungi

Fungal nanochitin can assist the transition from the linear fossil-based economy to a circular biobased economy given its environmental benefits over conventional crustacean-nanochitin. Its real-world implementation requires carefully assessing its toxicity so that unwanted human health and environmental issues are avoided. Accordingly, the cytotoxicity and inflammatory effects of chitin nanofibrils (ChNFs) from white mushroom is assessed. ChNFs are few nanometers in diameter, with a 75.8% N-acetylation degree, a crystallinity of 59.1%, and present a 44:56 chitin/glucan weight ratio. Studies are conducted for aqueous colloidal ChNF dispersions (0-5 mg·mL-1) and free-standing films having physically entangled ChNFs. Aqueous dispersions of chitin nanocrystals (ChNCs) isolated via hydrochloric acid hydrolysis of α-chitin powder are also evaluated for comparison. Cytotoxicity studies conducted in human fibroblasts (MRC-5 cells) and murine brain microglia (BV-2 cells) reveal a comparatively safer behavior over related biobased nanomaterials. However, a strong inflammatory response was observed when BV-2 cells were cultured in the presence of colloidal ChNFs. These novel cytotoxicity and inflammatory studies shed light on the potential of fungal ChNFs for biomedical applications.

Heterogeneous aggregation of carbon and silicon nanoparticles with benzo[a]pyrene modulates their impacts on the pulmonary surfactant film

Inhaled nanoparticles (NPs) can deposit in alveoli where they interact with the pulmonary surfactant (PS) and potentially induce toxicity. Although nano-bio interactions are influenced by the physicochemical properties of NPs, isolated NPs used in previous studies cannot accurately represent those found in atmosphere. Here we used molecular dynamics simulations to investigate the interplay between two types of NPs associated with benzo[a]pyrene (BaP) at the PS film. Silicon NPs (SiNPs), regardless of aggregation and adsorption, directly penetrated through the PS film with minimal disturbance. Meanwhile, BaPs adsorbed on SiNPs were rapidly solubilized by PS, increasing the BaP's bioaccessibility in alveoli. Carbon NPs (CNPs) showed aggregation and adsorption-dependent effects on the PS film. Compared to isolated CNPs, which extracted PS to form biomolecular coronas, aggregated CNPs caused more pronounced PS disruption, especially around irregularly shaped edges. SiNPs in mixture exacerbated the PS perturbation by piercing PS film around the site of CNP interactions. BaPs adsorbed on CNPs were less solubilized and suppressed PS extraction, but aggravated biophysical inhibition by prompting film collapse under compression. These results suggest that for proper assessment of inhalation toxicity of airborne NPs, it is imperative to consider their heterogeneous aggregation and adsorption of pollutants under atmospheric conditions.

Toxicity assessment of core-shell and superabsorbent polymers in cell-based systems

The identification of health risks arising from occupational exposure to submicron/nanoscale materials is of particular interest and toxicological investigations designed to assess their hazardous properties can provide valuable insights. The core-shell polymers poly (methyl methacrylate)@poly (methacrylic acid-co-ethylene glycol dimethacrylate) [PMMA@P (MAA-co-EGDMA)] and poly (n-butyl methacrylate-co-ethylene glycol dimethacrylate)@poly (methyl methacrylate) [P (nBMA-co-EGDMA)@PMMA] could be utilized for the debonding of coatings and for the encapsulation and targeted delivery of various compounds. The hybrid superabsorbent core-shell polymers poly (methacrylic acid-co-ethylene glycol dimethacrylate)@silicon dioxide [P (MAA-co-EGDMA)@SiO₂] could be utilized as internal curing agents in cementitious materials. Therefore, the characterization of their toxicological profile is essential to ensure their safety throughout manufacturing and the life cycle of the final products. Based on the above, the purpose of the present study was to assess the acute toxic effects of the above mentioned polymers on cell viability and on cellular redox state in EA. hy926 human endothelial cells and in RAW264.7 mouse macrophages. According to our results, the examined polymers did not cause any acute toxic effects on cell viability after any administration. However, the thorough evaluation of a panel of redox biomarkers revealed that they affected cellular redox state in a cell-specific manner. As regards EA. hy926 cells, the polymers disrupted redox homeostasis and promoted protein carbonylation. Concerning RAW264.7 cells, P (nBMA-co-EGDMA)@PMMA caused disturbances in redox equilibrium and special emphasis was placed on the triphasic dose-response effect detected in lipid peroxidation. Finally, P (MAA-co-EGDMA)@SiO₂ activated cellular adaptive mechanisms in order to prevent from oxidative damage.

Enhancing Pt(IV) Complexes' Anticancer Activity upon Encapsulation in Stimuli-Responsive Nanocages

Platinum-based chemotherapy is the first-line treatment for different cancer types, and in particular, for malignant pleural mesothelioma patients (a tumor histotype with urgent medical needs). Herein, a strategy is presented to stabilize, transport, and intracellularly release a platinumIV (PtIV ) prodrug using a breakable nanocarrier. Its reduction, and therefore activation as an anticancer drug, is promoted by the presence of glutathione in neoplastic cells that also causes the destruction of the carrier. The nanocage presents a single internal cavity in which the hydrophobic complex (Pt(dach)Cl2 (OH)2 ), (dach = R,R-diaminocyclohexane) is encapsulated. The in vitro uptake and the internalization kinetics in cancer model cells are evaluated and, using flow cytometry analysis, the successful release and activation of the Pt-based drug inside cancer cells are demonstrated. The in vitro findings are confirmed by the in vivo experiments on a mice model obtained by xenografting MPM487, a patient-derived malignant pleural mesothelioma. MPM487 confirms the well-known resistance of malignant pleural mesothelioma to cisplatin treatment while an interesting 50% reduction of tumor growth is observed when mice are treated with the PtIV , entrapped in the nanocages, at an equivalent dose of the platinum complex.

Enzybiotic-mediated antimicrobial functionalization of polyhydroxyalkanoates

Polymeric nanoparticles (NPs) present some ideal properties as biomedical nanocarriers for targeted drug delivery such as enhanced translocation through body barriers. Biopolymers, such as polyhydroxyalkanoates (PHAs) are gaining attention as nanocarrier biomaterials due to their inherent biocompatibility, biodegradability, and ability to be vehiculized through hydrophobic media, such as the lung surfactant (LS). Upon colonization of the lung alveoli, below the LS layer, Streptococcus pneumoniae, causes community-acquired pneumonia, a severe respiratory condition. In this work, we convert PHA NPs into an antimicrobial material by the immobilization of an enzybiotic, an antimicrobial enzyme, via a minimal PHA affinity tag. We first produced the fusion protein M711, comprising the minimized PHA affinity tag, MinP, and the enzybiotic Cpl-711, which specifically targets S. pneumoniae. Then, a PHA nanoparticulate suspension with adequate physicochemical properties for pulmonary delivery was formulated, and NPs were decorated with M711. Finally, we assessed the antipneumococcal activity of the nanosystem against planktonic and biofilm forms of S. pneumoniae. The resulting system displayed sustained antimicrobial activity against both, free and sessile cells, confirming that tag-mediated immobilization of enzybiotics on PHAs is a promising platform for bioactive antimicrobial functionalization.

Organ-on-chip systems as a model for nanomedicine

Nanomedicine is giving rise to increasing numbers of successful drugs, including cancer treatments, molecular imaging agents, and novel vaccine formulations. However, traditionally available model systems offer limited clinical translation and, compared to the number of preclinical studies, the approval rate of nanoparticles (NPs) for clinical use remains disappointingly low. A new paradigm of modeling biological systems on microfluidic chips has emerged in the last decade and is being gradually adopted by the nanomedicine community. These systems mimic tissues, organs, and diseases like cancer, on devices with small physical footprints and complex geometries. In this review, we report studies that used organ-on-chip approaches to study the interactions of NPs with biological systems. We present examples of NP toxicity studies, studies using biological NPs such as viruses, as well as modeling biological barriers and cancer on chip. Organ-on-chip systems present an exciting opportunity and can provide a renewed direction for the nanomedicine community.

Effects of silver nanoparticles on maternal mammary glands and offspring development under lactation exposure

The widespread applications of silver nanoparticles (AgNPs) throughout our daily lives have raised concerns regarding their environmental health and safety (EHS). Despite an increasing number of studies focused on the EHS impacts of AgNPs, there remain significant knowledge gaps with respect to their potential health impacts on susceptible populations, such as lactating mothers and infants. Herein, we aimed to investigate the deleterious effects of AgNPs with different sizes (20 and 40 nm) and surface coatings (PVP and BPEI) on maternal mice and their offspring following lactation exposure at doses of 20, 100 and 400 μg/kg body weight. We discovered that AgNPs could accumulate in the maternal mammary glands and disrupt the epithelial barrier in a dose-dependent manner. Notably, BPEI-coated AgNPs caused more damage to the mammary glands than PVP-coated particles. Importantly, we observed that, while AgNPs were distributed throughout the blood and main tissues, they were particularly enriched in the brains of breastfed offspring after maternal exposure during lactation, exhibiting exposure dosage- and particle coating-dependent patterns. Compared to PVP-coated nanoparticles, BPEI-coated AgNPs were more readily transferred to the offspring, possibly due to their enhanced deposition in maternal mammary glands. Moreover, we observed reduced body weight, blood cell toxicity, and tissue injuries in breastfed offspring whose dams received AgNPs. As a whole, these results reveal that maternal exposure to AgNPs results in the translocation of AgNPs into offspring via breastfeeding, inducing developmental impairments in these breastfed offspring. This study provides important new insights into the EHS impacts of AgNP consumption during lactation.

Advances in TEER measurements of biological barriers in microphysiological systems

Biological barriers are multicellular structures that precisely regulate the transport of ions, biomolecules, drugs, cells, and other organisms. Transendothelial/epithelial electrical resistance (TEER) is a label-free method for predicting the properties of biological barriers. Understanding the mechanisms that control TEER significantly enhances our knowledge of the physiopathology of different diseases and aids in the development of new drugs. Measuring TEER values within microphysiological systems called organ-on-a-chip devices that simulate the microenvironment, architecture, and physiology of biological barriers in the body provides valuable insight into the behavior of barriers in response to different drugs and pathogens. These integrated systems should increase the accuracy, reproducibility, sensitivity, resolution, high throughput, speed, cost-effectiveness, and reliable predictability of TEER measurements. Implementing advanced micro and nanoscale manufacturing techniques, surface modification methods, biomaterials, biosensors, electronics, and stem cell biology is necessary for integrating TEER measuring systems with organ-on-chip technology. This review focuses on the applications, advantages, and future perspectives of integrating organ-on-a-chip technology with TEER measurement methods for studying biological barriers. After briefly reviewing the role of TEER in the physiology and pathology of barriers, standard techniques for measuring TEER, including Ohm's law and impedance spectroscopy, and commercially available devices are described. Furthermore, advances in TEER measurement are discussed in multiple barrier-on-a-chip system models representing different organs. Finally, we outline future trends in implementing advanced technologies to design and fabricate nanostructured electrodes, complicated microfluidic chips, and membranes for more advanced and accurate TEER measurements.

DBDPE and ZnO NPs synergistically induce neurotoxicity of SK-N-SH cells and activate mitochondrial apoptosis signaling pathway and Nrf2-mediated antioxidant pathway

Decabromodiphenyl ethane (DBDPE), a new brominated flame retardant, could negatively affect neurobehavior and pose health risks to humans. Humans are also exposed to widely used nanomaterials. This study investigated the combined toxic effects and action types of DBDPE and Zinc oxide nanoparticles (ZnO NPs) on human neuroblastoma SK-N-SH cells and the toxicity mechanisms. DBDPE inhibited the viability of SK-N-SH cells by 21.87% at 25 mg/L. ZnO NPs synergistically exacerbated the toxic effects of DBDPE. DBDPE and ZnO NPs caused excessive ROS production and inhibition of antioxidant enzyme (SOD and GSH) activity in cells, thus causing oxidative cellular damage. Moreover, DBDPE and ZnO NPs caused apoptosis by disrupting mitochondrial kinetic homeostasis, reducing mitochondrial membrane potential (MMP), increasing cytochrome C release and regulating Bax/Bcl-2 and Caspase-3 mRNA and protein expression. DBDPE and ZnO NPs increased the mRNA expression of nuclear factor erythroid 2- related factor (Nrf2) and its downstream genes. The molecular mechanisms revealed that oxidative stress, apoptosis and mitochondrial dysfunction were the critical factors in combined cytotoxicity. The bioinformatics analysis further indicated that co-exposure affected Nrf2 activation, apoptotic factors expression and mitochondrial fusion. The findings enrich the risk perception of neurotoxicity caused by DBDPE and ZnO NPs.

Penetration and translocation of functional inorganic nanomaterials into biological barriers

With excellent physicochemical properties, inorganic nanomaterials (INMs) have exhibited a series of attractive applications in biomedical fields. Biological barriers prevent successful delivery of nanomedicine in living systems that limits the development of nanomedicine especially for sufficient delivery of drugs and effective therapy. Numerous researches have focused on overcoming these biological barriers and homogeneity of organisms to enhance therapeutic efficacy, however, most of these strategies fail to resolve these challenges. In this review, we present the latest progress about how INMs interact with biological barriers and penetrate these barriers. We also summarize that both native structure and components of biological barriers and physicochemical properties of INMs contributed to the penetration capacity. Knowledge about the relationship between INMs structure and penetration capacity will guide the design and application of functional and efficient nanomedicine in the future.

Deciphering the Effects of 2D Black Phosphorus on Disrupted Hematopoiesis and Pulmonary Immune Homeostasis Using a Developed Flow Cytometry Method

As an emerging two-dimensional nanomaterial with promising prospects, mono- or few-layer black phosphorus (BP) is potentially toxic to humans. We investigated the effects of two types of BPs on adult male mice through intratracheal instillation. Using the flow cytometry method, the generation, migration, and recruitment of immune cells in different organs have been characterized on days 1, 7, 14, and 21 post-exposure. Compared with small BP (S-BP, lateral size at ∼188 nm), large BP (L-BP, lateral size at ∼326 nm) induced a stronger stress lymphopoiesis and B cell infiltration into the alveolar sac. More importantly, L-BP dramatically increased peripheral neutrophil (NE) counts up to 1.9-fold on day 21 post-exposure. Decreased expression of the CXCR4 on NEs, an important regulator of NE retention in the bone marrow, explained the increased NE release into the circulation induced by L-BP. Therefore, BP triggers systemic inflammation via the disruption of both the generation and migration of inflammatory immune cells.

How Nanoparticles Open the Paracellular Route of Biological Barriers: Mechanisms, Applications, and Prospects

Biological barriers are essential physiological protective systems and obstacles to drug delivery. Nanoparticles (NPs) can access the paracellular route of biological barriers, either causing adverse health impacts on humans or producing therapeutic opportunities. This Review introduces the structural and functional influences of NPs on the key components that govern the paracellular route, mainly tight junctions, adherens junctions, and cytoskeletons. Furthermore, we evaluate their interaction mechanisms and address the influencing factors that determine the ability of NPs to open the paracellular route, which provides a better knowledge of how NPs can open the paracellular route in a safer and more controllable way. Finally, we summarize limitations in the research models and methodologies of the existing research in the field and provide future research direction. This Review demonstrates the in-depth causes for the reversible opening or destruction of the integrity of barriers generated by NPs; more importantly, it contributes insights into the design of NP-based medications to boost paracellular drug delivery efficiency.

Physiologically Based Pharmacokinetic Modeling of Nanoparticle Biodistribution: A Review of Existing Models, Simulation Software, and Data Analysis Tools

Cancer treatment and pharmaceutical development require targeted treatment and less toxic therapeutic intervention to achieve real progress against this disease. In this scenario, nanomedicine emerged as a reliable tool to improve drug pharmacokinetics and to translate to the clinical biologics based on large molecules. However, the ability of our body to recognize foreign objects together with carrier transport heterogeneity derived from the combination of particle physical and chemical properties, payload and surface modification, make the designing of effective carriers very difficult. In this scenario, physiologically based pharmacokinetic modeling can help to design the particles and eventually predict their ability to reach the target and treat the tumor. This effort is performed by scientists with specific expertise and skills and familiarity with artificial intelligence tools such as advanced software that are not usually in the "cords" of traditional medical or material researchers. The goal of this review was to highlight the advantages that computational modeling could provide to nanomedicine and bring together scientists with different background by portraying in the most simple way the work of computational developers through the description of the tools that they use to predict nanoparticle transport and tumor targeting in our body.

An Overview of Essential Microelements and Common Metallic Nanoparticles and Their Effects on Male Fertility

Numerous factors affect reproduction, including stress, diet, obesity, the use of stimulants, or exposure to toxins, along with heavy elements (lead, silver, cadmium, uranium, vanadium, mercury, arsenic). Metals, like other xenotoxins, can cause infertility through, e.g., impairment of endocrine function and gametogenesis or excess production of reactive oxygen species (ROS). The advancement of nanotechnology has created another hazard to human safety through exposure to metals in the form of nanomaterials (NMs). Nanoparticles (NPs) exhibit a specific ability to penetrate cell membranes and biological barriers in the human body. These ultra-fine particles (<100 nm) can enter the human body through the respiratory tract, food, skin, injection, or implantation. Once absorbed, NPs are transported to various organs through the blood or lymph. Absorbed NPs, thanks to ultrahigh reactivity compared to bulk materials in microscale size, disrupt the homeostasis of the body as a result of interaction with biological molecules such as DNA, lipids, and proteins; interfering with the functioning of cells, organs, and physiological systems; and leading to severe pathological dysfunctions. Over the past decades, much research has been performed on the reproductive effects of essential trace elements. The research hypothesis that disturbances in the metabolism of trace elements are one of the many causes of infertility has been unquestionably confirmed. This review examines the complex reproductive risks for men regarding the exposure to potentially harmless xenobiotics based on a series of 298 articles over the past 30 years. The research was conducted using PubMed, Web of Science, and Scopus databases searching for papers devoted to in vivo and in vitro studies related to the influence of essential elements (iron, selenium, manganese, cobalt, zinc, copper, and molybdenum) and widely used metallic NPs on male reproduction potential.

Engineering nano-drug biointerface to overcome biological barriers toward precision drug delivery

The rapid advancement of nanomedicine and nanoparticle (NP) materials presents novel solutions potentially capable of revolutionizing health care by improving efficacy, bioavailability, drug targeting, and safety. NPs are intriguing when considering medical applications because of their essential and unique qualities, including a significantly higher surface to mass ratio, quantum properties, and the potential to adsorb and transport drugs and other compounds. However, NPs must overcome or navigate several biological barriers of the human body to successfully deliver drugs at precise locations. Engineering the drug carrier biointerface can help overcome the main biological barriers and optimize the drug delivery in a more personalized manner. This review discusses the significant heterogeneous biological delivery barriers and how biointerface engineering can promote drug carriers to prevail over hurdles and navigate in a more personalized manner, thus ushering in the era of Precision Medicine. We also summarize the nanomedicines' current advantages and disadvantages in drug administration, from natural/synthetic sources to clinical applications. Additionally, we explore the innovative NP designs used in both non-personalized and customized applications as well as how they can attain a precise therapeutic strategy.

Perturbation of autophagy: An intrinsic toxicity mechanism of nanoparticles

Nanoparticles (NPs) have been widely used for various purposes due to their unique physicochemical properties. Such widespread applications greatly increase the possibility of human exposure to NPs in various ways. Once entering the human body, NPs may interfere with cellular homeostasis and thus affect the physiological system. As a result, it is necessary to evaluate the potential disturbance of NPs to multiple cell functions, including autophagy. Autophagy is an important cell function to maintain cellular homeostasis, and minimizing the disturbance caused by NP exposures to autophagy is critical to nanosafety. Herein, we summarized the recent research progress in nanotoxicity with particular focuses on the perturbation of NPs to cell autophagy. The basic processes of autophagy and complex relationships between autophagy and major human diseases were further discussed to emphasize the importance of keeping autophagy under control. Moreover, the most recent advances on perturbation of different types of NPs to autophagy were also reviewed. Last but not least, we also discussed major research challenges and potential coping strategies and proposed a safe-by-design strategy towards safer applications of NPs.

The Prospective Ameliorative Role of Zinc Oxide Nanoparticles in STZ-Induced Diabetic Nephropathy in Rats: Mechanistic Targeting of Autophagy and Regulating Nrf2/TXNIP/NLRP3 Inflammasome Signaling

Diabetic nephropathy (DN) as one of the common microvascular complications of diabetes mellitus, is the main cause of end-stage renal disease. Zinc oxide nanoparticles (ZnO NPs) have been employed in several biomedical aspects. This study purposed to explore the mechanistic renoprotective effects of ZnO NPs in STZ-induced DN. Sixty male Wistar rats were allocated into four equal groups: control, ZnO NPs control, STZ, and STZ + ZnO NPs groups. At the end of the experiment, blood and urine biochemical parameters were assayed. Renal tissue level of advanced glycation end products (AGEs) was assayed spectrofluorometrically, moreover, nuclear factor erythroid 2-related factor 2 (Nrf2) DNA-binding activity and IL-1β levels were detected by ELISA. The gene expression levels of thioredoxin-interacting protein (TXNIP) and NOD-like receptor family pyrin domain containing 3 (NLRP3) were detected by quantitative real-time PCR. Oxidative stress markers were determined spectrophotometrically. Also, renal tissue histopathological and immunohistochemical analyses were determined. After 6 weeks of treatment, ZnO NPs markedly improved the biochemical, renal functions, and histopathological findings. Furthermore, ZnO NPs significantly increased Nrf2-DNA-binding activity and downregulated TXNIP gene expression leading to restoration of the redox status. Additionally, ZnO NPs ameliorated AGEs levels, enhanced autophagy activity, and attenuated inflammasome activation via downregulation of NLRP3 expression and reducing IL-1β levels. Based on our results, we concluded that ZnO NPs can be considered as a promising agent for slowing the progression of DN via interplay between autophagy and Nrf2/TXNIP/NLRP3 inflammasome signaling.

Peptide-Conjugated Nano Delivery Systems for Therapy and Diagnosis of Cancer

Peptides are strings of approximately 2-50 amino acids, which have gained huge attention for theranostic applications in cancer research due to their various advantages including better biosafety, customizability, convenient process of synthesis, targeting ability via recognizing biological receptors on cancer cells, and better ability to penetrate cell membranes. The conjugation of peptides to the various nano delivery systems (NDS) has been found to provide an added benefit toward targeted delivery for cancer therapy. Moreover, the simultaneous delivery of peptide-conjugated NDS and nano probes has shown potential for the diagnosis of the malignant progression of cancer. In this review, various barriers hindering the targeting capacity of NDS are addressed, and various approaches for conjugating peptides and NDS have been discussed. Moreover, major peptide-based functionalized NDS targeting cancer-specific receptors have been considered, including the conjugation of peptides with extracellular vesicles, which are biological nanovesicles with promising ability for therapy and the diagnosis of cancer.

Carbon Dots: A Future Blood-Brain Barrier Penetrating Nanomedicine and Drug Nanocarrier

Drug delivery across the blood-brain barrier (BBB) is one of the biggest challenges in modern medicine due to the BBB's highly semipermeable property that limits most therapeutic agents of brain diseases to enter the central nervous system (CNS). In recent years, nanoparticles, especially carbon dots (CDs), exhibit many unprecedented applications for drug delivery. Several types of CDs and CD-ligand conjugates have been reported successfully penetrating the BBB, which shows a promising progress in the application of CD-based drug delivery system (DDS) for the treatment of CNS diseases. In this review, our discussion of CDs includes their classification, preparations, structures, properties, and applications for the treatment of neurodegenerative diseases, especially Alzheimer's disease (AD) and brain tumor. Moreover, abundant functional groups on the surface, especially amine and carboxyl groups, allow CDs to conjugate with diverse drugs as versatile drug nanocarriers. In addition, structure of the BBB is briefly described, and mechanisms for transporting various molecules across the BBB and other biological barriers are elucidated. Most importantly, recent developments in drug delivery with CDs as BBB-penetrating nanodrugs and drug nanocarriers to target CNS diseases especially Alzheimer's disease and brain tumor are summarized. Eventually, future prospects of the CD-based DDS are discussed in combination with the development of artificial intelligence and nanorobots.

Can nanomaterials induce reproductive toxicity in male mammals? A historical and critical review

The nanotechnology enabled the development of nanomaterials (NMs) with a variety of industrial, biomedical, and consumer applications. However, the mechanism of action (MoA) and toxicity of NMs remain unclear, especially in the male reproductive system. Thus, this study aimed to perform a bibliometric and systematic review of the literature on the toxic effects of different types of NMs on the male reproductive system and function in mammalian models. A series of 236 articles related to the in vitro and in vivo reproductive toxicity of NMs in mammalian models were analyzed. The data concerning the bioaccumulation, experimental conditions (types of NMs, species, cell lines, exposure period, and routes of exposure), and the MoA and toxicity of NMs were summarized and discussed. Results showed that this field of research began in 2005 and has experienced an exponential increase since 2012. Revised data confirmed that the NMs have the ability to cross the blood-testis barrier and bioaccumulate in several organs of the male reproductive system, such as testis, prostate, epididymis, and seminal vesicle. A similar MoA and toxicity were observed after in vitro and in vivo exposure to NMs. The NM reproductive toxicity was mainly related to ROS production, oxidative stress, DNA damage and apoptosis. In conclusion, the NM exposure induces bioaccumulation and toxic effects on male reproductive system of mammal models, confirming its potential risk to human and environmental health. The knowledge concerning the NM reproductive toxicity contributes to safety and sustainable use of nanotechnology.

Fetotoxicity of Nanoparticles: Causes and Mechanisms

The application of nanoparticles in consumer products and nanomedicines has increased dramatically in the last decade. Concerns for the nano-safety of susceptible populations are growing. Due to the small size, nanoparticles have the potential to cross the placental barrier and cause toxicity in the fetus. This review aims to identify factors associated with nanoparticle-induced fetotoxicity and the mechanisms involved, providing a better understanding of nanotoxicity at the maternal–fetal interface. The contribution of the physicochemical properties of nanoparticles (NPs), maternal physiological, and pathological conditions to the fetotoxicity is highlighted. The underlying molecular mechanisms, including oxidative stress, DNA damage, apoptosis, and autophagy are summarized. Finally, perspectives and challenges related to nanoparticle-induced fetotoxicity are also discussed.

Titanium Dioxide, but Not Zinc Oxide, Nanoparticles Cause Severe Transcriptomic Alterations in T98G Human Glioblastoma Cells

Titanium dioxide and zinc oxide are two of the most widely used nanomaterials. We assessed the effects of noncytotoxic doses of both nanomaterials on T98G human glioblastoma cells by omic approaches. Surprisingly, no effects on the transcriptome of T98G cells was detected after exposure to 5 µg/mL of zinc oxide nanoparticles during 72 h. Conversely, the transcriptome of the cells exposed to 20 µg/mL of titanium dioxide nanoparticles during 72 h revealed alterations in lots of biological processes and molecular pathways. Alterations to the transcriptome suggests that exposure to titanium dioxide nanoparticles might, potentially, compromise the integrity of the blood brain barrier integrity and cause neuroinflammation. The latter issue was further confirmed phenotypically with a proteomic analysis and by recording the release of interleukin 8. Titanium dioxide also caused autophagy, which was demonstrated through the increase in the expression of the autophagy-related 3 and microtubule associated protein 1 light chain 3 alpha genes. The proteomic analysis revealed that titanium dioxide nanoparticles might have anticancerigen properties by downregulating genes involved in the detoxication of anthracyclines. A risk assessment resulting from titanium dioxide exposure, focusing on the central nervous system as a potential target of toxicity, is necessary.

Electrodynamic assisted self-assembled fibrous hydrogel microcapsules: a novel 3D in vitro platform for assessment of nanoparticle toxicity

Nanoparticle (NP) toxicity assessment is a critical step in assessing the health impacts of NP exposure to both consumers and occupational workers. In vitro assessment models comprising cells cultured in a two-dimensional tissue culture plate (2D-TCP) are an efficient and cost-effective choice for estimating the safety risks of NPs. However, in vitro culture of cells in 2D-TCPs distorts cell–integrin and cell–cell interactions and is not able to replicate an in vivo phenotype. Three-dimensional (3D) in vitro platforms provide a unique alternative to bridge the gap between traditional 2D in vitro and in vivo models. In this study, novel microcapsules of alginate hydrogel incorporated with natural polymeric nanofibers (chitin nanofibrils) and synthetic polymeric nanofibers poly(lactide-co-glycolide) are designed as a 3D in vitro platform. This study demonstrates for the first time that electrodynamic assisted self-assembled fibrous 3D hydrogel (3D-SAF hydrogel) microcapsules with a size in the range of 300–500 μm in diameter with a Young's modulus of 12.7–42 kPa can be obtained by varying the amount of nanofibers in the hydrogel precursor solutions. The 3D-SAF microcapsules were found to mimic the in vivo cellular microenvironment for cells to grow, as evaluated using A549 cells. Higher cellular spreading and prolonged proliferation of A549 cells were observed in 3D-SAF microcapsules compared to control microcapsules without the nanofibers. The 3D-SAF microcapsule integrated well plate was used to assess the toxicity of model NPs, e.g., Al₂O₃ and ZnO. The toxicity levels of the model NPs were found to be dependent on the chemistry of the NPs and their physical agglomeration in the test media. Our results demonstrate that 3D-SAF microcapsules with an in vivo mimicking microenvironment can be developed as a physiologically relevant platform for high-throughput toxicity screening of NPs or pharmaceutical drugs.

Electrohydrodynamic-assisted fabrication of novel nano-net-nanofibrous 3D-SAF hydrogel microcapsules leads to them having tunable mechanical and cell adhesive properties that are applicable to diverse biomedical fields.

Gene Editing by Extracellular Vesicles

CRISPR/Cas technologies have advanced dramatically in recent years. Many different systems with new properties have been characterized and a plethora of hybrid CRISPR/Cas systems able to modify the epigenome, regulate transcription, and correct mutations in DNA and RNA have been devised. However, practical application of CRISPR/Cas systems is severely limited by the lack of effective delivery tools. In this review, recent advances in developing vehicles for the delivery of CRISPR/Cas in the form of ribonucleoprotein complexes are outlined. Most importantly, we emphasize the use of extracellular vesicles (EVs) for CRISPR/Cas delivery and describe their unique properties: biocompatibility, safety, capacity for rational design, and ability to cross biological barriers. Available molecular tools that enable loading of desired protein and/or RNA cargo into the vesicles in a controllable manner and shape the surface of EVs for targeted delivery into specific tissues (e.g., using targeting ligands, peptides, or nanobodies) are discussed. Opportunities for both endogenous (intracellular production of CRISPR/Cas) and exogenous (post-production) loading of EVs are presented.