Antitoxin nanoparticles: design considerations, functional mechanisms, and applications in toxin neutralization

The application of nanotechnology has significantly advanced the development of novel platforms that enhance disease treatment and diagnosis. A key innovation in this field is the creation of antitoxin nanoparticles (ATNs), designed to address toxin exposure. These precision-engineered nanosystems have unique physicochemical properties and selective binding capabilities, allowing them to effectively capture and neutralize toxins from various biological, chemical, and environmental sources. In this review, we thoroughly examine their therapeutic and diagnostic potential for managing toxin-related challenges. We also explore recent advancements and offer critical insights into the design and clinical implementation of ATNs.

Hyaluronic Acid Receptor-Mediated Nanomedicines and Targeted Therapy

Hyaluronic acid (HA) is a naturally occurring polysaccharide found in the extracellular matrix with broad applications in disease treatment. HA possesses good biocompatibility, biodegradability, and the ability to interact with various cell surface receptors. Its wide range of molecular weights and modifiable chemical groups make it an effective drug carrier for drug delivery. Additionally, the overexpression of specific receptors for HA on cell surfaces in many disease states enhances the accumulation of drugs at pathological sites through receptor binding. In this review, the modification of HA with drugs, major receptor proteins, and the latest advances in receptor-targeted nano drug delivery systems (DDS) for the treatment of tumors and inflammatory diseases are summarized. Furthermore, the functions of HA with varying molecular weights of HA in vivo and the selection of drug delivery methods for different diseases are discussed.

Achieving Endo/Lysosomal Escape Using Smart Nanosystems for Efficient Cellular Delivery

The delivery of therapeutic agents faces significant hurdles posed by the endo-lysosomal pathway, a bottleneck that hampers clinical effectiveness. This comprehensive review addresses the urgent need to enhance cellular delivery mechanisms to overcome these obstacles. It focuses on the potential of smart nanomaterials, delving into their unique characteristics and mechanisms in detail. Special attention is given to their ability to strategically evade endosomal entrapment, thereby enhancing therapeutic efficacy. The manuscript thoroughly examines assays crucial for understanding endosomal escape and cellular uptake dynamics. By analyzing various assessment methods, we offer nuanced insights into these investigative approaches' multifaceted aspects. We meticulously analyze the use of smart nanocarriers, exploring diverse mechanisms such as pore formation, proton sponge effects, membrane destabilization, photochemical disruption, and the strategic use of endosomal escape agents. Each mechanism's effectiveness and potential application in mitigating endosomal entrapment are scrutinized. This paper provides a critical overview of the current landscape, emphasizing the need for advanced delivery systems to navigate the complexities of cellular uptake. Importantly, it underscores the transformative role of smart nanomaterials in revolutionizing cellular delivery strategies, leading to a paradigm shift towards improved therapeutic outcomes.

Streamlining Skin Regeneration: A Ready-To-Use Silk Bilayer Wound Dressing

Silk proteins have been highlighted in the past decade for tissue engineering (TE) and skin regeneration due to their biocompatibility, biodegradability, and exceptional mechanical properties. While silk fibroin (SF) has high structural and mechanical stability with high potential as an external protective layer, traditionally discarded sericin (SS) has shown great potential as a natural-based hydrogel, promoting cell-cell interactions, making it an ideal material for direct wound contact. In this context, the present study proposes a new wound dressing approach by developing an SS/SF bilayer construct for full-thickness exudative wounds. The processing methodology implemented included an innovation element and the cryopreservation of the SS intrinsic secondary structure, followed by rehydration to produce a hydrogel layer, which was integrated with a salt-leached SF scaffold to produce a bilayer structure. In addition, a sterilization protocol was developed using supercritical technology (sCO2) to allow an industrial scale-up. The resulting bilayer material presented high porosity (>85%) and interconnectivity while promoting cell adhesion, proliferation, and infiltration of human dermal fibroblasts (HDFs). SS and SF exhibit distinct secondary structures, pore sizes, and swelling properties, opening new possibilities for dual-phased systems that accommodate the different needs of a wound during the healing process. The innovative SS hydrogel layer highlights the transformative potential of the proposed bilayer system for biomedical therapeutics and TE, offering insights into novel wound dressing fabrication.

Unlocking the Therapeutic Applicability of LNP-mRNA: Chemistry, Formulation, and Clinical Strategies

Messenger RNA (mRNA) has emerged as an innovative therapeutic modality, offering promising avenues for the prevention and treatment of a variety of diseases. The tremendous success of mRNA vaccines in effectively combatting coronavirus disease 2019 (COVID-19) evidences the unlimited medical and therapeutic potential of mRNA technology. Overcoming challenges related to mRNA stability, immunogenicity, and precision targeting has been made possible by recent advancements in lipid nanoparticles (LNPs). This review summarizes state-of-the-art LNP-mRNA-based therapeutics, including their structure, material compositions, design guidelines, and screening principles. Additionally, we highlight current preclinical and clinical trends in LNP-mRNA therapeutics in a broad range of treatments in ophthalmological conditions, cancer immunotherapy, gene editing, and rare-disease medicine. Particular attention is given to the translation and evolution of LNP-mRNA vaccines into a broader spectrum of therapeutics. We explore concerns in the aspects of inadequate extrahepatic targeting efficacy, elevated doses, safety concerns, and challenges of large-scale production procedures. This discussion may offer insights and perspectives on near- and long-term clinical development prospects for LNP-mRNA therapeutics.

RNA therapies for CNS diseases

Neurological disorders are a diverse group of conditions that pose an increasing health burden worldwide. There is a general lack of effective therapies due to multiple reasons, of which a key obstacle is the presence of the blood-brain barrier, which limits drug delivery to the central nervous system, and generally restricts the pool of candidate drugs to small, lipophilic molecules. However, in many cases, these are unable to target key pathways in the pathogenesis of neurological disorders. As a group, RNA therapies have shown tremendous promise in treating various conditions because they offer unique opportunities for specific targeting by leveraging Watson-Crick base pairing systems, opening up possibilities to modulate pathological mechanisms that previously could not be addressed by small molecules or antibody-protein interactions. This potential paradigm shift in disease management has been enabled by recent advances in synthesizing, purifying, and delivering RNA. This review explores the use of RNA-based therapies specifically for central nervous system disorders, where we highlight the inherent limitations of RNA therapy and present strategies to augment the effectiveness of RNA therapeutics, including physical, chemical, and biological methods. We then describe translational challenges to the widespread use of RNA therapies and close with a consideration of future prospects in this field.

Impact of conjugation to different lipids on the lymphatic uptake and biodistribution of brush PEG polymers

Delivery to peripheral lymphatics can be achieved following interstitial administration of nano-sized delivery systems (nanoparticles, liposomes, dendrimers etc) or molecules that hitchhike on endogenous nano-sized carriers (such as albumin). The published work concerning the hitchhiking approach has mostly focussed on the lymphatic uptake of vaccines conjugated directly to albumin binding moieties (ABMs such as lipids, Evans blue dye derivatives or peptides) and their subsequent trafficking into draining lymph nodes. The mechanisms underpinning access and transport of these constructs into lymph fluid, including potential interaction with other endogenous nanocarriers such as lipoproteins, have largely been ignored. Recently, we described a series of brush polyethylene glycol (PEG) polymers containing end terminal short-chain or medium-chain hydrocarbon tails (1C2 or 1C12, respectively), cholesterol moiety (Cho), or medium-chain or long-chain diacylglycerols (2C12 or 2C18, respectively). We evaluated the association of these materials with albumin and lipoprotein in rat plasma, and their intravenous (IV) and subcutaneous (SC) pharmacokinetic profiles. Here we fully detail the association of this suite of polymers with albumin and lipoproteins in rat lymph, which is expected to facilitate lymph transport of the materials from the SC injection site. Additionally, we characterise the thoracic lymph uptake, tissue and lymph node biodistribution of the lipidated brush PEG polymers following SC administration to thoracic lymph cannulated rats. All polymers had moderate lymphatic uptake in rats following SC dosing with the lymph uptake higher for 1C2-PEG, 2C12-PEG and 2C18-PEG (5.8%, 5.9% and 6.7% dose in lymph, respectively) compared with 1C12-PEG and Cho-PEG (both 1.5% dose in lymph). The enhanced lymph uptake of 1C2-PEG, 2C12-PEG and 2C18-PEG appeared related to their association profile with different lipoproteins. The five polymers displayed different biodistribution patterns in major organs and tissues in mice. All polymers reached immune cells deep within the inguinal lymph nodes of mice following SC dosing. The ability to access these immune cells suggests the potential of the polymers as platforms for the delivery of vaccines and immunotherapies. Future studies will focus on evaluating the lymphatic targeting and therapeutic potential of drug or vaccine-loaded polymers in pre-clinical disease models.

Progress in the Treatment of Central Nervous System Diseases Based on Nanosized Traditional Chinese Medicine

Traditional Chinese Medicine (TCM) is widely used in clinical practice to treat diseases related to central nervous system (CNS) damage. However, the blood-brain barrier (BBB) constitutes a significant impediment to the effective delivery of TCM, thus substantially diminishing its efficacy. Advances in nanotechnology and its applications in TCM (also known as nano-TCM) can deliver active ingredients or components of TCM across the BBB to the targeted brain region. This review provides an overview of the physiological and pathological mechanisms of the BBB and systematically classifies the common TCM used to treat CNS diseases and types of nanocarriers that effectively deliver TCM to the brain. Additionally, drug delivery strategies for nano-TCMs that utilize in vivo physiological properties or in vitro devices to bypass or cross the BBB are discussed. This review further focuses on the application of nano-TCMs in the treatment of various CNS diseases. Finally, this article anticipates a design strategy for nano-TCMs with higher delivery efficiency and probes their application potential in treating a wider range of CNS diseases.

Advanced Nanomaterials in Medical 3D Printing

3D printing is now recognized as a significant tool for medical research and clinical practice, leading to the emergence of medical 3D printing technology. It is essential to improve the properties of 3D-printed products to meet the demand for medical use. The core of generating qualified 3D printing products is to develop advanced materials and processes. Taking advantage of nanomaterials with tunable and distinct physical, chemical, and biological properties, integrating nanotechnology into 3D printing creates new opportunities for advancing medical 3D printing field. Recently, some attempts are made to improve medical 3D printing through nanotechnology, providing new insights into developing advanced medical 3D printing technology. With high-resolution 3D printing technology, nano-structures can be directly fabricated for medical applications. Incorporating nanomaterials into the 3D printing material system can improve the properties of the 3D-printed medical products. At the same time, nanomaterials can be used to expand novel medical 3D printing technologies. This review introduced the strategies and progresses of improving medical 3D printing through nanotechnology and discussed challenges in clinical translation.

Microfluidic synthesis of lipid-based nanoparticles for drug delivery: recent advances and opportunities

Microfluidic technologies are revolutionizing the synthesis of nanoscale lipid particles and enabling new opportunities for the production of lipid-based nanomedicines. By harnessing the benefits of microfluidics for controlling diffusive and advective transport within microfabricated flow cells, microfluidic platforms enable unique capabilities for lipid nanoparticle synthesis with precise and tunable control over nanoparticle properties. Here we present an assessment of the current state of microfluidic technologies for lipid-based nanoparticle and nanomedicine production. Microfluidic techniques are discussed in the context of conventional production methods, with an emphasis on the capabilities of microfluidic systems for controlling nanoparticle size and size distribution. Challenges and opportunities associated with the scaling of manufacturing throughput are discussed, together with an overview of emerging microfluidic methods for lipid nanomedicine post-processing. The impact of additive manufacturing on current and future microfluidic platforms is also considered.

Advanced optical imaging for the rational design of nanomedicines

Despite the enormous potential of nanomedicines to shape the future of medicine, their clinical translation remains suboptimal. Translational challenges are present in every step of the development pipeline, from a lack of understanding of patient heterogeneity to insufficient insights on nanoparticle properties and their impact on material-cell interactions. Here, we discuss how the adoption of advanced optical microscopy techniques, such as super-resolution optical microscopies, correlative techniques, and high-content modalities, could aid the rational design of nanocarriers, by characterizing the cell, the nanomaterial, and their interaction with unprecedented spatial and/or temporal detail. In this nanomedicine arena, we will discuss how the implementation of these techniques, with their versatility and specificity, can yield high volumes of multi-parametric data; and how machine learning can aid the rapid advances in microscopy: from image acquisition to data interpretation.

Hydrogel and Nanomedicine-Based Multimodal Therapeutic Strategies for Spinal Cord Injury

Spinal cord injury (SCI) is a severe neurodegenerative disease caused by mechanical and biological factors, manifesting as a loss of motor and sensory functions. Inhibition of injury expansion and even reversal of injury in the acute damage stage of SCI are important strategies for treating this disease. Hydrogels and nanoparticle (NP)-based drugs are the most effective, widely studied, and clinically valuable therapeutic strategies in the field of repair and regeneration. Hydrogels are 3D flow structures that fill the pathological gaps in SCI and provide a microenvironment similar to that of the spinal cord extracellular matrix for nerve cell regeneration. NP-based drugs can easily penetrate the blood-spinal cord barrier, target SCI lesions, and are noninvasive. Hydrogels and NPs as drug carriers can be loaded with various drugs and biological therapeutic factors for slow release in SCI lesions. They help drugs function more efficiently by exerting anti-inflammatory, antioxidant, and nerve regeneration effects to promote the recovery of neurological function. In this review, the use of hydrogels and NPs as drug carriers and the role of both in the repair of SCI are discussed to provide a multimodal strategic reference for nerve repair and regeneration after SCI.

Chitosan and Cyclodextrins-Versatile Materials Used to Create Drug Delivery Systems for Gastrointestinal Cancers

Gastrointestinal cancers are characterized by a frequent incidence, a high number of associated deaths, and a tremendous burden on the medical system and patients worldwide. As conventional chemotherapeutic drugs face numerous limitations, researchers started to investigate better alternatives for extending drug efficacy and limiting adverse effects. A remarkably increasing interest has been addressed to chitosan and cyclodextrins, two highly versatile natural carbohydrate materials endowed with unique physicochemical properties. In this respect, numerous studies reported on fabricating various chitosan and cyclodextrin-based formulations that enabled prolonged circulation times, improved cellular internalization of carried drugs, preferential uptake by the targeted cells, reduced side effects, enhanced apoptosis rates, and increased tumor suppression rates. Therefore, this paper aims to briefly present the advantageous properties of these oligo- and polysaccharides for designing drug delivery systems, further focusing the discussion on nanocarrier systems based on chitosan/cyclodextrins for treating different gastrointestinal cancers. Specifically, there are reviewed studies describing promising solutions for colorectal, liver, gastric, pancreatic, and other types of cancers of the digestive system towards creating an updated framework of what concerns anticancer chitosan/cyclodextrin-based drug delivery systems.

Combination of irinotecan silicasome nanoparticles with radiation therapy sensitizes immunotherapy by modulating the activation of the cGAS/STING pathway for colorectal cancer

Our previous clinical trial (Identifier: NCT02605265) revealed that addition of irinotecan (IRIN) to neoadjuvant chemoradiotherapy for rectal cancer could improve the curative effect. However, the adverse effects caused by IRIN limited the wide application of IRIN chemoradiotherapy. This study aimed to explore the mechanism under the synergistic effects of IRIN plus radiation therapy in colorectal cancer (CRC) cells and optimization of IRIN delivery via a silicasome nanocarrier in vivo. Our results revealed that compared with single IRIN or radiation treatment, IRIN combined with radiation therapy remarkably activated the intracellular cGAS/STING pathway, and promoted the expression levels of major histocompatibility complex class I (MHC-I) and programmed death ligand 1 (PD-L1). Further, a silicasome (mesoporous silica nanoparticle coated with lipid bilayer) nanocarrier was utilized to improve the delivery of IRIN with enhanced efficacy and reduced side effects. In the MC38 CRC syngeneic tumor model, IRIN silicasome combined with radiation therapy demonstrated a greater antitumor efficacy than free IRIN plus radiation therapy. Flow cytometry showed the increased number of CD4+ T cells, CD8+ T cells, and dendritic cells (DCs) in tumor in the IRIN silicasome plus radiation group. The immunofluorescence staining further confirmed the activated immune microenvironment with the elevated interferon-γ (IFN-γ) deposition. Besides, the antitumor effect of IRIN silicasome plus radiation therapy was synergistically enhanced by anti-PD-1 immunotherapy. These findings indicated that the combination of IRIN silicasome with radiation therapy could sensitize immunotherapy by manipulating the cGAS/STING pathway serving as a new strategy for CRC treatment.

Microfluidic synthesis of nanomaterials for biomedical applications

The field of nanomaterials has progressed dramatically over the past decades with important contributions to the biomedical area. The physicochemical properties of nanomaterials, such as the size and structure, can be controlled through manipulation of mass and heat transfer conditions during synthesis. In particular, microfluidic systems with rapid mixing and precise fluid control are ideal platforms for creating appropriate synthesis conditions. One notable example of microfluidics-based synthesis is the development of lipid nanoparticle (LNP)-based mRNA vaccines with accelerated clinical translation and robust efficacy during the COVID-19 pandemic. In addition to LNPs, microfluidic systems have been adopted for the controlled synthesis of a broad range of nanomaterials. In this review, we introduce the fundamental principles of microfluidic technologies including flow field- and multiple field-based methods for fabricating nanoparticles, and discuss their applications in the biomedical field. We conclude this review by outlining several major challenges and future directions in the implementation of microfluidic synthesis of nanomaterials.

Gene therapy for inherited retinal diseases: exploiting new tools in genome editing and nanotechnology

Inherited retinal diseases (IRDs) encompass a diverse group of genetic disorders that lead to progressive visual impairment and blindness. Over the years, considerable strides have been made in understanding the underlying molecular mechanisms of IRDs, laying the foundation for novel therapeutic interventions. Gene therapy has emerged as a compelling approach for treating IRDs, with notable advancements achieved through targeted gene augmentation. However, several setbacks and limitations persist, hindering the widespread clinical success of gene therapy for IRDs. One promising avenue of research is the development of new genome editing tools. Cutting-edge technologies such as CRISPR-Cas9 nucleases, base editing and prime editing provide unprecedented precision and efficiency in targeted gene manipulation, offering the potential to overcome existing challenges in gene therapy for IRDs. Furthermore, traditional gene therapy encounters a significant challenge due to immune responses to viral vectors, which remain crucial obstacles in achieving long-lasting therapeutic effects. Nanotechnology has emerged as a valuable ally in the quest to optimize gene therapy outcomes for ocular diseases. Nanoparticles engineered with nanoscale precision offer improved gene delivery to specific retinal cells, allowing for enhanced targeting and reduced immunogenicity. In this review, we discuss recent advancements in gene therapy for IRDs and explore the setbacks that have been encountered in clinical trials. We highlight the technological advances in genome editing for the treatment of IRDs and how integrating nanotechnology into gene delivery strategies could enhance the safety and efficacy of gene therapy, ultimately offering hope for patients with IRDs and potentially paving the way for similar advancements in other ocular disorders.

Transferrin-Targeted Liposomes in Glioblastoma Therapy: A Review

Glioblastoma (GBM) is a highly aggressive brain tumor, and its treatment is further complicated by the high selectivity of the blood-brain barrier (BBB). The scientific community is urgently seeking innovative and effective therapeutic solutions. Liposomes are a promising new tool that has shown potential in addressing the limitations of chemotherapy, such as poor bioavailability and toxicity to healthy cells. However, passive targeting strategies based solely on the physicochemical properties of liposomes have proven ineffective due to a lack of tissue specificity. Accordingly, the upregulation of transferrin receptors (TfRs) in brain tissue has led to the development of TfR-targeted anticancer therapeutics. Currently, one of the most widely adopted methods for improving drug delivery in the treatment of GBM and other neurological disorders is the utilization of active targeting strategies that specifically target this receptor. In this review, we discuss the role of Tf-conjugated liposomes in GBM therapy and present some recent studies investigating the drug delivery efficiency of Tf-liposomes; in addition, we address some challenges currently facing this approach to treatment and present some potential improvement possibilities.

Pulmonary Delivery of Specialized Pro-Resolving Mediators-Based Nanotherapeutics Attenuates Pulmonary Fibrosis in Preclinical Animal Models

Pulmonary fibrosis (PF) is a chronic lung disease characterized by excess extracellular matrix deposition and prolonged inflammation that fails to resolve and is druggable. Using resolvins and their precursors for inflammation resolution, we demonstrate a nano-enabled approach for accomplishing robust antifibrotic effects in bleomycin- or engineered nanomaterial-induced mouse and rat PF models. Targeting the lipid peroxidation-triggered NLRP3 inflammasome and NF-κB pathway in macrophages and the ROS-mediated TGF-β/Smad and S1P signaling in epithelial cells results in these potent protective effects at the ng/mL dosimetry. We further develop an inhalable biocompatible nanoparticle that encapsulates fish oil, a chosen resolvin precursor, with phosphatidylcholine and polyethylene glycol to enhance drug permeability and facilitate crossing the mucosal barrier, forming "fish-oilsome" (FOS). Oropharyngeal aspiration and inhalation of FOS improved the anti-inflammatory status, histological characteristics, and pulmonary function in fibrotic lungs, which was mechanistically supported by transcriptomic and proteomic analyses. Further, scale-up engineered FOS samples with the desired physicochemical properties, anti-PF efficacy, and in vivo biocompatibility were validated in different batch sizes (up to 0.2 L/batch). This study provides a practical and translatable approach to promoting inflammation resolution and PF treatment.

Development and Upscaling of SiO2@TiO2 Core-Shell Nanoparticles for Methylene Blue Removal

SiO2@TiO2 core-shell nanoparticles were successfully synthesized via a simple, reproducible, and low-cost method and tested for methylene blue adsorption and UV photodegradation, with a view to their application in wastewater treatment. The monodisperse SiO2 core was obtained by the classical Stöber method and then coated with a thin layer of TiO2, followed by calcination or hydrothermal treatments. The properties of SiO2@TiO2 core-shell NPs resulted from the synergy between the photocatalytic properties of TiO2 and the adsorptive properties of SiO2. The synthesized NPs were characterized using FT-IR spectroscopy, HR-TEM, FE-SEM, and EDS. Zeta potential, specific surface area, and porosity were also determined. The results show that the synthesized SiO2@TiO2 NPs that are hydrothermally treated have similar behaviors and properties regardless of the hydrothermal treatment type and synthesis scale and better performance compared to the SiO2@TiO2 calcined and TiO2 reference samples. The generation of reactive species was determined by EPR, and the photocatalytic activity was evaluated by the methylene blue (MB) removal in aqueous solution under UV light. Hydrothermally treated SiO2@TiO2 showed the highest adsorption capacity and photocatalytic removal of almost 100% of MB after 15 min in UV light, 55 and 89% higher compared to SiO2 and TiO2 reference samples, respectively, while the SiO2@TiO2 calcined sample showed 80%. It was also observed that the SiO2-containing samples showed a considerable adsorption capacity compared to the TiO2 reference sample, which improved the MB removal. These results demonstrate the efficient synergy effect between SiO2 and TiO2, which enhances both the adsorption and photocatalytic properties of the nanomaterial. A possible photocatalytic mechanism was also proposed. Also noteworthy is that the performance of the upscaled HT1 sample was similar to one of the lab-scale synthesized samples, demonstrating the potentiality of this synthesis methodology in producing candidate nanomaterials for the removal of contaminants from wastewater.

Microfluidic Devices: A Tool for Nanoparticle Synthesis and Performance Evaluation

The use of nanoparticles (NPs) in nanomedicine holds great promise for the treatment of diseases for which conventional therapies present serious limitations. Additionally, NPs can drastically improve early diagnosis and follow-up of many disorders. However, to harness their full capabilities, they must be precisely designed, produced, and tested in relevant models. Microfluidic systems can simulate dynamic fluid flows, gradients, specific microenvironments, and multiorgan complexes, providing an efficient and cost-effective approach for both NPs synthesis and screening. Microfluidic technologies allow for the synthesis of NPs under controlled conditions, enhancing batch-to-batch reproducibility. Moreover, due to the versatility of microfluidic devices, it is possible to generate and customize endless platforms for rapid and efficient in vitro and in vivo screening of NPs' performance. Indeed, microfluidic devices show great potential as advanced systems for small organism manipulation and immobilization. In this review, first we summarize the major microfluidic platforms that allow for controlled NPs synthesis. Next, we will discuss the most innovative microfluidic platforms that enable mimicking in vitro environments as well as give insights into organism-on-a-chip and their promising application for NPs screening. We conclude this review with a critical assessment of the current challenges and possible future directions of microfluidic systems in NPs synthesis and screening to impact the field of nanomedicine.

Enrichment of nano delivery platforms for mRNA-based nanotherapeutics

Lipid-based nanoparticles (LNP) have shown significant progress in delivering mRNA for therapeutics, particularly with the success of coronavirus disease 2019 (COVID-19) vaccines. However, there are still challenges, such as organ-specific targeting, sustained protein expression, immunogenicity, and storage that need to be addressed. Therefore, there is interest in developing additional nano drug delivery systems (DDS) to complement LNP technology. Some of these include polymer, lipid-polymer hybrid, organic/inorganic hybrid nanostructure, and inorganic nanoparticle. In our opinion, LNP technology may not be suitable for every disease scenario in categories such as infection disease, cancer, pulmonary disease, autoimmune disorders and genetic rare disease (among others). This is because different diseases may require distinct administration routes, doses, and treatment durations, as well as considerations for biological barriers that may lower the efficacy and/or exert safety concern. In this perspective, we will highlight the need and potential for enhancing the diversity of nano delivery platforms for mRNA-based nanotherapeutics.

Engineered Design of a Mesoporous Silica Nanoparticle-Based Nanocarrier for Efficient mRNA Delivery in Vivo

We have developed tailor-designed mesoporous silica nanoparticles (MSNPs) specifically for delivering mRNA. Our unique assembly protocol involves premixing mRNA with a cationic polymer and then electrostatically binding it to the MSNP surface. Since the key physicochemical parameters of MSNPs could influence the biological outcome, we also investigated the roles of size, porosity, surface topology, and aspect ratio on the mRNA delivery. These efforts allow us to identify the best-performing carrier, which was able to achieve efficient cellular uptake and intracellular escape while delivering a luciferase mRNA in mice. The optimized carrier remained stable and active for at least 7 days after being stored at 4 °C and was able to enable tissue-specific mRNA expression, particularly in the pancreas and mesentery after intraperitoneal injection. The optimized carrier was further manufactured in a larger batch size and found to be equally efficient in delivering mRNA in mice and rats, without any obvious toxicity.

Chitosan/Albumin Coating Factorial Optimization of Alginate/Dextran Sulfate Cores for Oral Delivery of Insulin

The design of nanoparticle formulations composed of biopolymers, that govern the physicochemical properties of orally delivered insulin, relies on improving insulin stability and absorption through the intestinal mucosa while protecting it from harsh conditions in the gastrointestinal (GI) tract. Chitosan/polyethylene glycol (PEG) and albumin coating of alginate/dextran sulfate hydrogel cores are presented as a multilayer complex protecting insulin within the nanoparticle. This study aims to optimize a nanoparticle formulation by assessing the relationship between design parameters and experimental data using response surface methodology through a 3-factor 3-level optimization Box–Behnken design. While the selected independent variables were the concentrations of PEG, chitosan and albumin, the dependent variables were particle size, polydispersity index (PDI), zeta potential, and insulin release. Experimental results showed a nanoparticle size ranging from 313 to 585 nm, with PDI from 0.17 to 0.39 and zeta potential ranging from −29 to −44 mV. Insulin bioactivity was maintained in simulated GI media with over 45% cumulative release after 180 min in a simulated intestinal medium. Based on the experimental responses and according to the criteria of desirability on the experimental region’s constraints, solutions of 0.03% PEG, 0.047% chitosan and 1.20% albumin provide an optimum nanoparticle formulation for insulin oral delivery.

Ultrasound-mediated nano drug delivery for treating cancer: Fundamental physics to future directions

The application of biocompatible nanocarriers in medicine has provided several benefits over conventional treatment methods. However, achieving high treatment efficacy and deep penetration of nanocarriers in tumor tissue is still challenging. To address this, stimuli-responsive nano-sized drug delivery systems (DDSs) are an active area of investigation in delivering anticancer drugs. While ultrasound is mainly used for diagnostic purposes, it can also be applied to affect cellular function and the delivery/release of anticancer drugs. Therapeutic ultrasound (TUS) has shown potential as both a stand-alone anticancer treatment and a method to induce targeted drug release from nanocarrier systems. TUS approaches have been used to overcome various physiological obstacles, including endothelial barriers, the tumor microenvironment (TME), and immunological hurdles. Combining nanomedicine and ultrasound as a smart DDS can increase in situ drug delivery and improve access to impermeable tissues. Furthermore, smart DDSs can perform targeted drug release in response to distinctive TMEs, external triggers, or dual/multi-stimulus. This results in enhanced treatment efficacy and reduced damage to surrounding healthy tissue or organs at risk. Integrating DDSs and ultrasound is still in its early stages. More research and clinical trials are required to fully understand ultrasound's underlying physical mechanisms and interactions with various types of nanocarriers and different types of cells and tissues. In the present review, ultrasound-mediated nano-sized DDS, specifically focused on cancer treatment, is presented and discussed. Ultrasound interaction with nanoparticles (NPs), drug release mechanisms, and various types of ultrasound-sensitive NPs are examined. Additionally, in vitro, in vivo, and clinical applications of TUS are reviewed in light of the critical challenges that need to be considered to advance TUS toward an efficient, secure, straightforward, and accessible cancer treatment. This study also presents effective TUS parameters and safety considerations for this treatment modality and gives recommendations about system design and operation. Finally, future perspectives are considered, and different TUS approaches are examined and discussed in detail. This review investigates drug release and delivery through ultrasound-mediated nano-sized cancer treatment, both pre-clinically and clinically.

Design of Diselenide-Bridged Hyaluronic Acid Nano-antioxidant for Efficient ROS Scavenging to Relieve Colitis

Overproduction of reactive oxygen species (ROS), a key characteristic of inflammatory bowel disease (IBD), is responsible for dysregulation of signal transduction, inflammatory response, and DNA damage, which ultimately leads to disease progression and deterioration. Thus, ROS scavenging has become a promising strategy to navigate IBD. Inspired by the targeting capability of hyaluronic acid (HA) to CD44-overexpressed inflammatory cells together with the redox regulation capacity of diselenide compounds, we developed an oral nanoformulation, i.e., diselenide-bridged hyaluronic acid nanogel (SeNG), with a view to treat colitis through a ROS scavenging mechanism. Our data demonstrated that SeNG specifically accumulated in colitis tissue that was mediated by highly efficient CD44-HA interaction. This has allowed us to demonstrate a significant anti-inflammatory effect in an acute colitis mouse model induced by dextran sulfate sodium and trinitrobenzenesulfonic acid. Mechanistically, we continued to show SeNG reduced the ROS level via both direct elimination and up-regulation of the Nrf2/HO-1 signal pathway. Collectively, our work provides proof-of-principle evidence for a SeNG-mediated nano-antioxidant strategy, by which colitis could be effectively managed.

Reducing Postoperative Recurrence of Early-Stage Hepatocellular Carcinoma by a Wound-Targeted Nanodrug

New strategies to decrease risk of relapse after surgery are needed for improving 5-year survival rate of hepatocellular carcinoma (HCC). To address this need, a wound-targeted nanodrug is developed, that contains an immune checkpoint inhibitor (anti-PD-L1)and an angiogenesis inhibitor (sorafenib)). These nanoparticles consist of highly biocompatible mesoporous silica (MSNP) that is surface-coated with platelet membrane (PM) to achieve surgical site targeting in a self-amplified accumulation manner. Sorafenib is introduced into the MSNP pores while covalently attaching anti-PD-L1 antibody on the PM surface. The resulting nano-formulation, abbreviated as a-PM-S-MSNP, can effectively target the surgical margin when intraperitoneally (IP) administered into an immune competent murine orthotopic HCC model. Multiple administrations of a-PM-S-MSNP generate potent anti-HCC effect and significantly prolong overall mice survival. Immunophenotyping and immunochemistry staining reveal the signatures of favorable anti-HCC immunity and anti-angiogenesis effect at tumor sites. More importantly, microscopic inspection of a-PM-S-MSNP treated mice shows that 2 out 6 are histologically tumor-free, which is in sharp contrast to the control mice where tumor foci can be easily identified. The data suggest that a-PM-S-MSNP can efficiently inhibit post-surgical HCC relapse without obvious side effects and holds considerable promise for clinical translation as a novel nanodrug.

Prussian Blue Nanozymes with Enhanced Catalytic Activity: Size Tuning and Application in ELISA-like Immunoassay

Prussian blue nanozymes possessing peroxidase-like activity gather significant attention as alternatives to natural enzymes in therapy, biosensing, and environmental remediation. Recently, Prussian blue nanoparticles with enhanced catalytic activity prepared by reduction of FeCl₃/K₃[Fe(CN)₆] mixture have been reported. These nanoparticles were denoted as ‘artificial peroxidase’ nanozymes. Our study provides insights into the process of their synthesis. We studied how the size of nanozymes and synthesis yield can be controlled via adjustment of the synthesis conditions. Based on these results, we developed a reproducible and scalable method for the preparation of ‘artificial peroxidase’ with tunable sizes and enhanced catalytic activity. Nanozymes modified with gelatin shell and functionalized with affine molecules were applied as labels in colorimetric immunoassays of prostate-specific antigen and tetanus antibodies, enabling detection of these analytes in the range of clinically relevant concentrations. Protein coating provides excellent colloidal stability of nanozymes in physiological conditions and stability upon long-term storage.

Synthesis and Application of Albumin Nanoparticles Loaded with Prussian Blue Nanozymes

Prussian blue nanozymes exhibit peroxidase-like catalytic activity and are therefore considered a stable and inexpensive alternative to natural peroxidases in the enzyme-linked immunosorbent assay (ELISA). In this work, we propose a robust method of Prussian blue nanozyme functionalization, which relies on the entrapment of nanozymes into albumin nanoparticles. The principle of the method is the addition of ethanol to a solution that contains albumin and nanozymes. At a high ethanol concentration solubility of albumin decreases, resulting in the formation of albumin nanoparticles loaded with nanozymes. The hydrodynamic diameter of nanoparticles was between 120 and 230 nm and depended on the nanozyme-to-BSA ratio. Encapsulation efficiency of nanozymes reached 96–99% and up to 190 μg of nanozymes were loaded per 1 mg of nanoparticles. Nanoparticles were stable at pH 5.5–7.5 and upon long-term storage in deionized water. Excellent reproducibility of the synthesis procedure was confirmed by the preparation of three individual batches of Prussian-blue-loaded BSA nanoparticles with almost identical properties. Nanoparticles were functionalized with monoclonal antibodies using glutaraldehyde cross-linking. The resulting conjugates were applied as labels in an ELISA-like assay of tumor marker prostate-specific antigen (PSA). The lower limit of detection was below 1 ng/mL, which enables measurement of PSA in the range of clinically relevant concentrations.

Volumetric Scalability of Microfluidic and Semi-Batch Silk Nanoprecipitation Methods

Silk fibroin nanoprecipitation by organic desolvation in semi-batch and microfluidic formats provides promising bottom-up routes for manufacturing narrow polydispersity, spherical silk nanoparticles. The translation of silk nanoparticle production to pilot, clinical, and industrial scales can be aided through insight into the property drifts incited by nanoprecipitation scale-up and the identification of critical process parameters to maintain throughout scaling. Here, we report the reproducibility of silk nanoprecipitation on volumetric scale-up in low-shear, semi-batch systems and estimate the reproducibility of chip parallelization for volumetric scale-up in a high shear, staggered herringbone micromixer. We showed that silk precursor feeds processed in an unstirred semi-batch system (mixing time > 120 s) displayed significant changes in the nanoparticle physicochemical and crystalline properties following a 12-fold increase in volumetric scale between 1.8 and 21.9 mL while the physicochemical properties stayed constant following a further 6-fold increase in scale to 138 mL. The nanoparticle physicochemical properties showed greater reproducibility after a 6-fold volumetric scale-up when using lower mixing times of greater similarity (8.4 s and 29.4 s) with active stirring at 400 rpm, indicating that the bulk mixing time and average shear rate should be maintained during volumetric scale-up. Conversely, microfluidic manufacture showed high between-batch repeatability and between-chip reproducibility across four participants and microfluidic chips, thereby strengthening chip parallelization as a production strategy for silk nanoparticles at pilot, clinical, and industrial scales.

Rutin-Loaded Nanovesicles for Improved Stability and Enhanced Topical Efficacy of Natural Compound

Rutin is a natural compound with several pharmacological effects. Among these, antioxidant activity is one of the best known. Despite its numerous benefits, its topical application is severely limited by its physicochemical properties. For this reason, the use of suitable systems could be necessary to improve its delivery through skin, thus enhancing its pharmacological effects. In this regard, the aim of this work is to optimize the ethosomal dispersion modifying both lipid and ethanol concentrations and encapsulating different amounts of rutin. Characterization studies performed on the realized systems highlighted their great stability properties. Studies of encapsulation efficiency and loading degree allowed us to identify a better formulation (EE% 67.5 ± 5.2%, DL% 27 ± 1.7%), which was used for further analyses. The data recorded from in vitro studies showed that the encapsulation into these nanosystems allowed us to overcome the photosensitivity limitation of rutin. Indeed, a markable photostability of the loaded formulation was recorded, compared with that reported from the free rutin solution. The efficacy of the nanosystems was finally evaluated both in vitro on keratinocyte cells and in vivo on human healthy volunteers. The results confirmed the potentiality of rutin-loaded nanosystems for skin disease, mainly related to their anti-inflammatory and antioxidant effects.