Form Follows Function: Nanoparticle Shape and Its Implications for Nanomedicine

Elongated self-assembled nanocarriers: From molecular organization to therapeutic applications

Self-assembled cylindrical aggregates made of amphiphilic molecules emerged almost 40 years ago. Due to their length up to micrometers, those particles display original physico-chemical properties such as important flexibility and, for concentrated samples, a high viscoelasticity making them suitable for a wide range of industrial applications. However, a quarter of century was needed to successfully take advantage of those improvements towards therapeutic purposes. Since then, a wide diversity of biocompatible materials such as polymers, lipids or peptides, have been developed to design self-assembling elongated drug nanocarriers, suitable for therapeutic or diagnostic applications. More recently, the investigation of the main forces driving the unidirectional growth of these nanodevices allowed a translation toward the formation of pure nanodrugs to avoid the use of unnecessary side materials and the possible toxicity concerns associated.

Integrating Biomaterials and Genome Editing Approaches to Advance Biomedical Science

The recent discovery and subsequent development of the CRISPR-Cas9 (clustered regularly interspaced short palindromic repeat-CRISPR-associated protein 9) platform as a precise genome editing tool have transformed biomedicine. As these CRISPR-based tools have matured, multiple stages of the gene editing process and the bioengineering of human cells and tissues have advanced. Here, we highlight recent intersections in the development of biomaterials and genome editing technologies. These intersections include the delivery of macromolecules, where biomaterial platforms have been harnessed to enable nonviral delivery of genome engineering tools to cells and tissues in vivo. Further, engineering native-like biomaterial platforms for cell culture facilitates complex modeling of human development and disease when combined with genome engineering tools. Deeper integration of biomaterial platforms in these fields could play a significant role in enabling new breakthroughs in the application of gene editing for the treatment of human disease.

Rough Carbon-Iron Oxide Nanohybrids for Near-Infrared-II Light-Responsive Synergistic Antibacterial Therapy

Infections caused by multidrug resistant bacteria are still a serious threat to human health. It is of great significance to explore effective alternative antibacterial strategies. Herein, carbon-iron oxide nanohybrids with rough surfaces (RCF) are developed for NIR-II light-responsive synergistic antibacterial therapy. RCF with excellent photothermal property and peroxidase-like activity could realize synergistic photothermal therapy (PTT)/chemodynamic therapy (CDT) in the NIR-II biowindow with improved penetration depth and low power density. More importantly, RCF with rough surfaces shows increased bacterial adhesion, thereby benefiting both CDT and PTT through effective interaction between RCF and bacteria. In vitro antibacterial experiments demonstrate a broad-spectrum synergistic antibacterial effect of RCF against Gram-negative Escherichia coli (E. coli), Gram-positive Staphylococcus aureus (S. aureus), and methicillin-resistant Staphylococcus aureus (MRSA). In addition, satisfactory biocompatibility makes RCF a promising antibacterial agent. Notably, the synergistic antibacterial performances in vivo could be achieved employing the rat wound model with MRSA infection. The current study proposes a facile strategy to construct antibacterial agents for practical antibacterial applications by the rational design of both composition and morphology. RCF with low power density NIR-II light responsive synergistic activity holds great potential in the effective treatment of drug-resistant bacterial infections.

Pollen-Mimetic Metal-Organic Frameworks with Tunable Spike-Like Nanostructures That Promote Cell Interactions to Improve Antigen-Specific Humoral Immunity

The exine capsules of pollen particles exhibit a variety of characteristic surface morphologies that promote their cell interactions; their use as antigen carriers for vaccination has been proposed. However, the allergy-causing substances in pollen particles may not all be removed, even by vigorous chemical treatments. To resolve this issue, this work develops systemic approaches for synthesizing pollen-mimetic metal-organic frameworks (MOFs), which comprise aluminum (Al) ions and an organic linker (2-aminoterephthalic acid), with tunable spike-like nanostructures on their surfaces. The as-synthesized MOFs act not only as a delivery vehicle that carries a model antigen (ovalbumin, OVA) but also as an adjuvant (Al). Scanning and transmission electron microscopies images reveal that the aspect ratio of the nanospikes that are grown on the MOFs can be controlled. A higher aspect ratio of the nanospikes on the MOFs is associated with greater cell attachment and faster and more efficient phagocytosis in cells, which results in greater expressions of pro-inflammatory cytokines. Consequently, a more robust immune response against the antigen of interest is elicited. These findings have broad implications for the rational design of the future antigen/adjuvant-presenting particles for vaccination.

Understanding nano-engineered particle-cell interactions: biological insights from mathematical models

Understanding the interactions between nano-engineered particles and cells is necessary for the rational design of particles for therapeutic, diagnostic and imaging purposes. In particular, the informed design of particles relies on the quantification of the relationship between the physicochemical properties of the particles and the rate at which cells interact with, and subsequently internalise, particles. Quantitative models, both mathematical and computational, provide a powerful tool for elucidating this relationship, as well as for understanding the mechanisms governing the intertwined processes of interaction and internalisation. Here we review the different types of mathematical and computational models that have been used to examine particle-cell interactions and particle internalisation. We detail the mathematical methodology for each type of model, the benefits and limitations associated with the different types of models, and highlight the advances in understanding gleaned from the application of these models to experimental observations of particle internalisation. We discuss the recent proposal and ongoing community adoption of standardised experimental reporting, and how this adoption is an important step toward unlocking the full potential of modelling approaches. Finally, we consider future directions in quantitative models of particle-cell interactions and highlight the need for hybrid experimental and theoretical investigations to address hitherto unanswered questions.

Exploring the transformability of polymer-lipid hybrid nanoparticles and nanomaterial-biology interplay to facilitate tumor penetration, cellular uptake and intracellular targeting of anticancer drugs

BACKGROUND

Successful delivery of anticancer drugs to intracellular targets requires different properties of the nanocarrier to overcome multiple transport barriers. However, few nanocarrier systems, to date, possess such properties, despite knowledge about the biological fate of inorganic and polymeric nanocarriers in relation to their fixed size, shape and surface properties. Herein, a polymer-lipid hybrid nanoparticle (PLN) system is described with size and shape transformability and its mechanisms of cellular uptake and intracellular trafficking are studied.

METHODS

Pharmaceutical lipids were screened for use in transformable PLN. Mechanisms of cellular uptake and the role of fatty acid-binding proteins in intracellular trafficking of PLN were investigated in breast cancer cells. Intra-tumoral penetration and retention of doxorubicin (DOX) were evaluated by confocal microscopy.

RESULTS

The lead PLNs showed time-dependent size reduction and shape change from spherical to spiky shape. This transformability of PLNs and lipid trafficking pathways facilitated intracellular transport of DOX-loaded PLN (DOX-PLN) into mitochondria and nuclei. DOX-PLN significantly increased DOX penetration and retention over free DOX or non-transformable liposomal DOX particles at 4 h post-intravenous administration.

CONCLUSION

Transformability of PLN and lipid-biology interplay can be exploited to design new nanocarriers for effective drug delivery to tumor cells and intracellular targets.

Asymmetries in the Electronic Properties of Spheroidal Metallic Nanoparticles, Revealed by Conduction Electron Spin Resonance and Surface Plasmon Resonance

Using electron spin resonance spectroscopy, we demonstrate that the morphological asymmetries present in small spheroidal metallic nanoparticles give rise to asymmetries in the behavior of electrons held in states near the metal's Fermi energy. We find that the effects of morphological asymmetries for these spheroidal systems are more important than the effects of size distributions when explaining the asymmetry in electronic behavior. This is found to be true for all the particles examined, which were made from Cu, Ag, Pd, Ir, Pt, and Au, bearing dodecanethiolate ligands. In the case of the Ag particles, we also demonstrate that the same model used to account for morphological effects in the electron spin resonance spectra can be used to account for small asymmetries present in the plasmon spectrum. This result demonstrates that the electronic properties of even small particles are tunable via morphological changes.

Effects on immunization of the physicochemical parameters of particles as vaccine carriers

Vaccination has milestone significance for the prophylactic and complete elimination of infectious diseases. However, combating malignant infectious diseases, such as Ebola or HIV, remains a challenge. It is necessary to explore novel technologies to facilitate the immune profile of vaccines. Particles exhibit a remarkable ability to modulate sophisticated immunity because of their intrinsic adjuvanticity or codelivery with immunostimulatory molecules. Recently, particles have been broadly investigated as carriers for vaccine delivery. Their physicochemical parameters (e.g., size, shape, and surface chemistry) significantly influence their in vivo fate and subsequent immunization effect. Herein, we highlight several types of particulate carrier used in the delivery of vaccines. We also examine how to engineer the physical and chemical characteristics of particulate adjuvants to make them robust candidates for a versatile vaccine delivery platform.

Advances in regulating physicochemical properties of mesoporous silica nanocarriers to overcome biological barriers

Mesoporous silica nanoparticles (MSNs) with remarkable structural features have been proven to be an excellent platform for the delivery of therapeutic molecules. Biological barriers in various forms (e.g., mucosal barrier, cellular barrier, gastrointestinal barrier, blood-brain barrier, and blood-tumor barrier) present substantial obstacles for MSNs. The physicochemical parameters of MSNs are known to be effective and tunable not only for load and release of therapeutic molecules but also for their biological responsiveness that is beneficial for cells and tissues. This review innovatively provides a description of how and why physicochemical properties (e.g., particle size, morphology, surface charge, hydrophilic-hydrophobic property, and surface modification) of MSNs influence their ability to cross the biological barriers prior to reaching targeted sites. First, the structural and physiological features of biological barriers are outlined. Next, the recent progresses in the critical physicochemical parameters of MSNs are highlighted from physicochemical and biological aspects. Surface modification, as an important strategy for achieving rapid transport, is also reviewed with special attention to the latest findings of bioactive groups and molecular mechanisms. Furthermore, advanced designs of multifunction intelligent MSNs to surmount the blood-tumor barrier and to actively target tumor sites are demonstrated in detail. Lastly, the biodegradability and toxicity of MSNs are evaluated. With perspectives for their potential application and biosafety, the clues in summary might lead to drug delivery with high efficiency and provide useful knowledge for rational design of nanomaterials.

Adsorption Kinetics of Oppositely Charged Hard and Soft Nanoparticles with Phospholipid Membranes

Nanoparticles (NPs) have great potential for biological applications as typically they exhibit strongly size-dependent properties. Specifically, the interaction of NPs with phospholipid membranes is significantly relevant to nanomedicine and the related field of nanotoxicology. Therefore, the investigation of interactions of NPs with model membranes is not only fundamentally important but also practically valuable to understand interactions of NPs with more complex cell membranes. Here, we report on the interaction of anionic vesicles of different charge densities and cationic SiO₂ NPs, either covered by a bare surface functionalized with amino moieties (-NH₂) or covered by poly[2-(dimethylamino) ethyl methacrylate]. We studied the kinetics of binding of NPs to the vesicle surface by time-resolved scattering experiments. A key result of the study is that binding is favored in the presence of electrostatic attraction, but the polymer layer decreases the binding rate drastically.

Controlled Synthesis and Surface Engineering of Janus Chitosan-Gold Nanoparticles for Photoacoustic Imaging-Guided Synergistic Gene/Photothermal Therapy

The unsymmetrical morphology and unique properties of Janus nanoparticles (JNPs) provide superior performances for biomedical applications. In this work, a general and facile strategy is developed to construct a series of symmetrical and unsymmetrical chitosan/gold nanoparticles. Taking advantage of the active motion derived from Janus structure, selective surface functionalization of polysaccharide domain, and photothermal effect of gold nanorods, Janus chitosan/gold nanoparticles (J-Au-CS) are selected as a model system to construct Janus-structured chitosan/gold nanohybrids (J-ACP). Near-infrared (NIR)-responsive J-ACP composed of polycationic chitosan nanospheres and PEGylated gold nanorods hold great potential to realize photoacoustic (PA) imaging-guided complementary photothermal therapy (PTT)/gene therapy for breast cancer. The morphology effect of chitosan/gold nanostructures on enhanced PTT, cellular uptake, and gene transfection is investigated. The feasibility of PA imaging to track the accumulation of J-ACP and guide PTT is also explored. Notably, synergistic therapy is achieved based on PTT-enhanced gene therapy. In addition, the loading function of chitosan/gold nanoparticles for fluorescence imaging is demonstrated. The current work extends the application of JNPs for imaging-guided synergistic cancer therapy and provides flexible candidates with distinct structures for diverse biomedical applications.

Biphasic synthesis of biodegradable urchin-like mesoporous organosilica nanoparticles for enhanced cellular internalization and precision cascaded therapy

It is widely accepted that a small particle size and rough surface can enhance tumor tissue accumulation and tumor cellular uptake of nanoparticles, respectively. Herein, sub-50 nm urchin-inspired disulfide bond-bridged mesoporous organosilica nanoparticles (UMONs) featured with a spiky surface and glutathione (GSH)-responsive biodegradability were successfully synthesized by a facile one-pot biphasic synthesis strategy for enhanced cellular internalization and tumor accumulation. l-Arginine (LA) is encapsulated into the mesopores of UMONs, whose outer surface is capped with the gatekeeper of ultrasmall gold nanoparticles, i.e., UMONs-LA-Au. On the one hand, the mild acidity-activated uncapping of ultrasmall gold can realize a tumor microenvironment (TME)-responsive release of LA. On the other hand, the unique natural glucose oxidase (GOx)-mimicking catalytic activity of ultrasmall gold can catalyze the decomposition of intratumoral glucose to produce acidic hydrogen peroxide (H₂O₂) and gluconic acid. Remarkably, these products can not only further facilitate the release of LA, but also catalyze the LA-H₂O₂ reaction for an increased nitric oxide (NO) yield, which realizes synergistic catalysis-enhanced NO gas therapy for tumor eradication. The judiciously fabricated UMONs-LA-Au present a paradigm of TME-responsive nanoplatforms for both enhanced cellular uptake and tumor-specific precision cascaded therapy, which broadens the range of practical biomedical applications and holds a significant promise for the clinical translation of silica-based nanotheranostics.

Investigating Spatial Heterogeneity of Nanoparticles Movement in Live Cells with Pair-Correlation Microscopy and Phasor Analysis

How nanoparticles distribute in living cells and overcome cellular barriers are important criteria in the design of drug carriers. Pair-correlation microscopy is a correlation analysis of fluctuation in the fluorescence intensity obtained by a confocal line scan that can quantify the dynamic properties of nanoparticle diffusion including the number of mobile nanoparticles, diffusion coefficient, and transit time across a spatial distance. Due to the potential heterogeneities in nanoparticle properties and the complexity within the cellular environment, quantification of averaged auto- and pair-correlation profiles may obscure important insights into the ability of nanoparticles to deliver drugs. To overcome this issue, we used phasor analysis to develop a data standardizing method, which can segment the scanned line into several subregions according to diffusion and address the spatial heterogeneity of nanoparticles moving inside cells. The phasor analysis is a fit-free method that represents autocorrelation profiles for each pixel relative to free diffusion on the so-called phasor plots. Phasor plots can then be used to select subpopulations for which the auto- and pair-correlation analysis can be performed separately. We demonstrate the phasor analysis for pair-correlation microscopy for investigating 16 nm, Cy5-labeled silica nanoparticles diffusing across the plasma membrane and green fluorescent proteins (GFP) diffusing across nuclear envelope in MCF-7 cells.

TRITC-Loaded PLGA Nanoparticles as Drug Delivery Carriers in Mouse Oocytes and Embryos

The structural layers around oocytes make it difficult to deliver drugs aimed at treating infertility. In this study, we sought to identify nanoparticles (NPs) that could easily pass through zona pellucida (ZP), a special layer around oocytes, for use as a drug delivery carrier. Three types of NPs were tested: quantum dot NPs, PE-polyethylene glycol (PEG)-loaded poly(lactic-co-glycolic acid) (PLGA) NPs (PEG/PL), and tetramethylrhodamine-loaded PLGA NPs (TRNPs). When mouse oocytes were treated with NPs, only TRNPs could fully pass through the ZP and cell membrane. To assess the effects of TRNPs on fertility and potential nanotoxicity, we performed mRNA sequencing analysis to confirm their genetic safety. We established a system to successfully internalize TRNPs into oocytes. The genetic stability and normal development of TRNP-treated oocytes and embryos were confirmed. These results imply that TRNPs can be used as a drug delivery carrier applicable to germ cells.

Supramolecular cancer nanotheranostics

Among the many challenges in medicine, the treatment and cure of cancer remains an outstanding goal given the complexity and diversity of the disease. Nanotheranostics, the integration of therapy and diagnosis in nanoformulations, is the next generation of personalized medicine to meet the challenges in precise cancer diagnosis, rational management and effective therapy, aiming to significantly increase the survival rate and improve the life quality of cancer patients. Different from most conventional platforms with unsatisfactory theranostic capabilities, supramolecular cancer nanotheranostics have unparalleled advantages in early-stage diagnosis and personal therapy, showing promising potential in clinical translations and applications. In this review, we summarize the progress of supramolecular cancer nanotheranostics and provide guidance for designing new targeted supramolecular theranostic agents. Based on extensive state-of-the-art research, our review will provide the existing and new researchers a foundation from which to advance supramolecular cancer nanotheranostics and promote translationally clinical applications.

Highly Efficient Photothermal Therapy with Cell-Penetrating Peptide-Modified Bumpy Au Triangular Nanoprisms using Low Laser Power and Low Probe Dose

Photothermal therapy (PTT) exploits nanomaterials with optimal heat conversion and cellular penetration using near-infrared (NIR) laser irradiation. However, current PTT agents suffer from inefficient heat conversion, poor intracellular delivery, and a high dose of probes along with excessive laser irradiation, causing limited therapeutic outcomes. Here, bumpy Au triangular nanoprisms (BATrisms) are developed for increasing the surface area, improving cell penetration, shifting the absorption peak to the NIR region, and enhancing the photothermal conversion efficiency (∼86%). Further, leucine (L)- and lysine (K)-rich cell-penetrating peptides (LK peptides) were employed to largely improve their cellular uptake efficiency. Importantly, a significant in vivo therapeutic efficacy with LK-BATrisms was demonstrated in a triple-negative breast cancer xenograft mice model. A very small dose of LK-BATrism (2.5 μg Au) was enough to exert antitumor efficacy under very low laser power (808 nm, 0.25 W/cm²), causing minimal tissue damages while very efficiently killing cancer cells.

Development of Non-Porous Silica Nanoparticles towards Cancer Photo-Theranostics

Nanoparticles have demonstrated several advantages for biomedical applications, including for the development of multifunctional agents as innovative medicine. Silica nanoparticles hold a special position among the various types of functional nanoparticles, due to their unique structural and functional properties. The recent development of silica nanoparticles has led to a new trend in light-based nanomedicines. The application of light provides many advantages for in vivo imaging and therapy of certain diseases, including cancer. Mesoporous and non-porous silica nanoparticles have high potential for light-based nanomedicine. Each silica nanoparticle has a unique structure, which incorporates various functions to utilize optical properties. Such advantages enable silica nanoparticles to perform powerful and advanced optical imaging, from the in vivo level to the nano and micro levels, using not only visible light but also near-infrared light. Furthermore, applications such as photodynamic therapy, in which a lesion site is specifically irradiated with light to treat it, have also been advancing. Silica nanoparticles have shown the potential to play important roles in the integration of light-based diagnostics and therapeutics, termed "photo-theranostics". Here, we review the recent development and progress of non-porous silica nanoparticles toward cancer "photo-theranostics".

Investigating the influence of block copolymer micelle length on cellular uptake and penetration in a multicellular tumor spheroid model

The efficient penetration of drug nanocarriers into tumors is an important prerequisite for therapeutic and diagnostic success. The physicochemical properties of nanocarriers, including size, shape and surface chemistry have been shown to influence their transport in biological systems. Recent studies have shown that elongated nanoparticles (NPs) can exhibit advantageous properties in comparison to spherical NPs, but these experiments have involved a variety of different materials, many of which are characterized by a broad size distribution. Here we describe a series of rigid rod-like micelles of uniform width, with narrow length distributions, and common surface chemistry, and examine their cell uptake and penetration into multicellular tumor spheroids (MCTSs) formed from two human breast cancer cell lines (MDA-MB-436 and MDB-MB-231). These micelles were prepared from a polyferrocenylsilane (PFS) diblock copolymer (BCP) with a corona block consisting of a statistical polymer of aminopropyl methacrylamide and oligo(ethyleneglycol methacrylate) (PFS₂₇-b-PAPMA₃-stat-POEGMA₄₈). The rigid rod micelles, with a common width (12 nm) and lengths ranging from 80 to 2000 nm, were prepared by seeded growth crystallization-driven self-assembly in ethanol and then transferred to water. To consider whether changing the shape of these micelles affects its uptake and penetration behavior, analogous spherical micelles were prepared by direct nanoprecipitation into water. Both micelle shape and length were found to influence cellular uptake and penetration into 500 μm MCTSs. Laser confocal fluorescence microscopy was used to examine penetration of these micelles into three-dimensional MCTS up to 90 μm depth. Micelles with an elongated shape and short length (80 nm) demonstrated the deepest penetration into the MCTSs formed by MDA-MB-436 cells. Micelles with lengths of 200 nm also showed substantial penetration into these MCTS, but the extent and depth of tumor penetration of the rod-like micelles decreased with increasing aspect ratio. MCTS of MDA-MB-231 cells had a less dense, more open structure than those formed by MDA-MB-436 cells. Here more extensive penetration was observed, particularly for the longer micelle samples.

Morphology-Controlled Synthesis of ZnO Nanostructures for Caffeine Degradation and Escherichia coli Inactivation in Water

Photocatalytic and antibacterial activity of nanoparticles are strongly governed by their morphology. By varying the type of solvent used, one can obtain different shapes of ZnO nanoparticles and tune the amount of reactive oxygen species (ROS) and metal ion (Zn2+) generation, which in turn dictates their activity. ZnO nanostructures were fabricated via facile wet chemical method by varying the type of solvents. Solar light assisted photocatalytic degradation of caffeine and antibacterial activity against E. coli were examined in presence ZnO nanostructures. In addition to an elaborate nanoparticle characterization, adsorption and kinetic experiments were performed to determine the ability of nanostructures to degrade caffeine. Zone of inhibition, time kill assay and electron microscopy imaging were carried out to assess the antibacterial activity. Experimental findings indicate that ZnO nanospheres generated maximum ROS and Zn2+ ions followed by ZnO nanopetals and ZnO nanorods. As a result, ZnO nanospheres exhibited highest degradation of caffeine as well as killing of E. coli. While ROS is mainly responsible for the photocatalytic activity of nanostructures, their antibacterial activity is mostly due to the combination of ROS, metal ion, physical attrition and cell internalization.

Cl−-Induced selective fabrication of 3D AgCl microcrystals by a one-pot synthesis method

Cl⁻ induces the shape evolution of AgCl crystals with different morphologies.

Untargeted metabolomics for Achilles heel of engineered nanomaterials' risk assessment

Owing to the superlative properties, engineered nanomaterials (ENM) are being used in food, cosmetics, medicine, and electronics. Therefore, exogenous ENM can be housed into humans through a multitude of exposure routes, leading to compromise of the biomolecules' functionalities through structural deformations, and even at the metabolic level. Consequently, it is of great importance to understand the perturbations introduced at the metabolic level for the timely risk assessment (RA) of ENM. Current technological advancements in metabolomics empower us to visualize the metabolic dysregulations in biological cells, tissues, and living objects, instigated by the ENM. Given the fact, we propose multitiered untargeted metabolomics for the risk assessment of ENM. We propose largely validated experimental design principles that enable the well-organized and authentic identification of metabolic dysregulation connected with a newly engineered nanomaterial. Our scheme could participate in the enhanced transparency of the RA course of rapidly emerging ENM.

Pterocladiella capillacea-stabilized silver nanoparticles as a green approach toward antibacterial biomaterials

Eco-friendly synthesis of AgNPs using P. capillacea extracts for antibacterial materials.

Ultra-thin patchy polymer-coated graphene oxide as a novel anticancer drug carrier

PISA generated polymer pimples on single graphene oxide sheets maintain colloidal stability for the adsorption and release of DOX.

Uptake quantification of gold nanoparticles inside of cancer cells using high order image correlation spectroscopy

The application of gold nanoparticles (AuNPs) in cancer therapeutics and diagnostics has recently reached a clinical level. Functional use of the AuNP in theranostics first requires effective uptake into the cells, but accurate quantification of AuNPs cellular uptake in real-time is still a challenge due to the destructive nature of existing characterization methods. The optical imaging-based quantification method is highly desirable. Here, we propose the use of high-order image correlation spectroscopy (HICS) as an optical imaging-based nanoparticle quantification technique. Coupled with dark field microscopy (DFM), a non-destructive and easy quantification method could be achieved. We demonstrate HICS analysis on 80 nm AuNPs coated with cetyltrimethylammonium bromide (CTAB) uptake in HeLa cells to calculate the percentage of aggregate species (dimer) in the total uptake and their relative scattering quantum yield inside the cells, the details of which are not available with other quantification techniques. The total particle uptake kinetics measured were in a reasonable agreement with the literature.

Nanoapproaches to Modifying Epigenetics of Epithelial Mesenchymal Transition for Treatment of Pulmonary Fibrosis

Idiopathic Pulmonary Fibrosis (IPF) is a chronically progressive interstitial lung that affects over 3 M people worldwide and rising in incidence. With a median survival of 2-3 years, IPF is consequently associated with high morbidity, mortality, and healthcare burden. Although two antifibrotic therapies, pirfenidone and nintedanib, are approved for human use, these agents reduce the rate of decline of pulmonary function but are not curative and do not reverse established fibrosis. In this review, we discuss the prevailing epithelial injury hypothesis, wherein pathogenic airway epithelial cell-state changes known as Epithelial Mesenchymal Transition (EMT) promotes the expansion of myofibroblast populations. Myofibroblasts are principal components of extracellular matrix production that result in airspace loss and mortality. We review the epigenetic transition driving EMT, a process produced by changes in histone acetylation regulating mesenchymal gene expression programs. This mechanistic work has focused on the central role of bromodomain-containing protein 4 in mediating EMT and myofibroblast transition and initial preclinical work has provided evidence of efficacy. As nanomedicine presents a promising approach to enhancing the efficacy of such anti-IPF agents, we then focus on the state of nanomedicine formulations for inhalable delivery in the treatment of pulmonary diseases, including liposomes, polymeric nanoparticles (NPs), inorganic NPs, and exosomes. These nanoscale agents potentially provide unique properties to existing pulmonary therapeutics, including controlled release, reduced systemic toxicity, and combination delivery. NP-based approaches for pulmonary delivery thus offer substantial promise to modify epigenetic regulators of EMT and advance treatments for IPF.

Engineering the drug carrier biointerface to overcome biological barriers to drug delivery

Micro and nanoscale drug carriers must navigate through a plethora of dynamic biological systems prior to reaching their tissue or disease targets. The biological obstacles to drug delivery come in many forms and include tissue barriers, mucus and bacterial biofilm hydrogels, the immune system, and cellular uptake and intracellular trafficking. The biointerface of drug carriers influences how these carriers navigate and overcome biological barriers for successful drug delivery. In this review, we examine how key material design parameters lead to dynamic biointerfaces and improved drug delivery across biological barriers. We provide a brief overview of approaches used to engineer key physicochemical properties of drug carriers, such as morphology, surface chemistry, and topography, as well as the development of dynamic responsive materials for barrier navigation. We then discuss essential biological barriers and how biointerface engineering can enable drug carriers to better navigate and overcome these barriers to drug delivery.

Synthesis and applications of anisotropic nanoparticles with precisely defined dimensions

Shape and size play powerful roles in determining the properties of a material; controlling these aspects with precision is therefore an important, fundamental goal of the chemical sciences. In particular, the introduction of shape anisotropy at the nanoscale has emerged as a potent way to access new properties and functionality, enabling the exploration of complex nanomaterials across a range of applications. Recent advances in DNA and protein nanotechnology, inorganic crystallization techniques, and precision polymer self-assembly are now enabling unprecedented control over the synthesis of anisotropic nanoparticles with a variety of shapes, encompassing one-dimensional rods, dumbbells and wires, two-dimensional and three-dimensional platelets, rings, polyhedra, stars, and more. This has, in turn, enabled much progress to be made in our understanding of how anisotropy and particle dimensions can be tuned to produce materials with unique and optimized properties. In this Review, we bring these recent developments together to critically appraise the different methods for the bottom-up synthesis of anisotropic nanoparticles enabling exquisite control over morphology and dimensions. We highlight the unique properties of these materials in arenas as diverse as electron transport and biological processing, illustrating how they can be leveraged to produce devices and materials with otherwise inaccessible functionality. By making size and shape our focus, we aim to identify potential synergies between different disciplines and produce a road map for future research in this crucial area.

Networks of High Aspect Ratio Particles to Direct Colloidal Assembly Dynamics and Cellular Interactions

Injectable colloids that self-assemble into three-dimensional networks are promising materials for applications in regenerative engineering, as they create open systems for cellular infiltration, interaction, and activation. However, most injectable colloids have spherical morphologies, which lack the high material-biology contact areas afforded by higher aspect ratio materials. To address this need, injectable high aspect ratio particles (HARPs) were developed that form three-dimensional networks to enhance scaffold assembly dynamics and cellular interactions. HARPs were functionalized for tunable surface charge through layer-by-layer electrostatic assembly. Positively charged Chitosan-HARPs had improved particle suspension dynamics when compared to spherical particles or negatively charged HARPs. Chit-HARPs were used to improve the suspension dynamics and viability of MIN6 cells in three-dimensional networks. When combined with negatively charged gelatin microsphere (GelMS) porogens, Chit-HARPs reduced GelMS sedimentation and increased overall network suspension, due to a combination of HARP network formation and electrostatic interactions. Lastly, HARPs were functionalized with fibroblast growth factor 2 (FGF2) to highlight their use for growth factor delivery. FGF2-HARPs increased fibroblast proliferation through a combination of 3D scaffold assembly and growth factor delivery. Taken together, these studies demonstrate the development and diverse uses of high aspect ratio particles as tunable injectable scaffolds for applications in regenerative engineering.

Mechanistic Approaches of Internalization, Subcellular Trafficking, and Cytotoxicity of Nanoparticles for Targeting the Small Intestine

Targeting the small intestine employing nanotechnology has proved to be a more effective way for site-specific drug delivery. The drug targeting to the small intestine can be achieved via nanoparticles for its optimum bioavailability within the systemic circulation. The small intestine is a remarkable candidate for localized drug delivery. The intestine has its unique properties. It has a less harsh environment than the stomach, provides comparatively more retention time, and possesses a greater surface area than other parts of the gastrointestinal tract. This review focuses on elaborating the intestinal barriers and approaches to overcome these barriers for internalizing nanoparticles and adopting different cellular trafficking pathways. We have discussed various factors that contribute to nanocarriers' cellular uptake, including their surface chemistry, surface morphology, and functionalization of nanoparticles. Furthermore, the fate of nanoparticles after their uptake at cellular and subcellular levels is also briefly explained. Finally, we have delineated the strategies that are adopted to determine the cytotoxicity of nanoparticles.

Rational design of nanomedicine for photothermal-chemodynamic bimodal cancer therapy

Given the diversity, complexity, and heterogeneity of persistent tumors, traditional nanoscale monotherapeutic systems suffer from dissatisfactory curative efficiency with incidence of metastasis or relapse. In parallel, the trend of clinical research on the basis of nanomedicines has increasingly shifted from monotherapy toward combinatorial therapy for admirable synergetic performances. In this regard, cutting-edge nanomedicines harnessing photothermal-chemodynamic bimodal therapy (PTT/CDT) have opened up a highly-efficient and relatively-safe cancer theranostic paradigm. Still, the integration of PTT/CDT functional units into one nanomedicine remains a herculean but meaningful task to achieve notable super-additive effects. This review aims to elucidate underlying synergistic interactions of PTT/CDT and highlight intriguing designs of nanomedicines for PTT/CDT including nanomaterial selection, performance optimization, multimodal therapy, visualization strategies, and targeting strategies. Furthermore, an outlook on further improvements of PTT/CDT is provided, emphasizing significant scientific issues that require remediation for clinical translation. This article is categorized under: Diagnostic Tools > in vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Understanding Nanoparticle Toxicity to Direct a Safe-by-Design Approach in Cancer Nanomedicine

Nanomedicine is a rapidly growing field that uses nanomaterials for the diagnosis, treatment and prevention of various diseases, including cancer. Various biocompatible nanoplatforms with diversified capabilities for tumor targeting, imaging, and therapy have materialized to yield individualized therapy. However, due to their unique properties brought about by their small size, safety concerns have emerged as their physicochemical properties can lead to altered pharmacokinetics, with the potential to cross biological barriers. In addition, the intrinsic toxicity of some of the inorganic materials (i.e., heavy metals) and their ability to accumulate and persist in the human body has been a challenge to their translation. Successful clinical translation of these nanoparticles is heavily dependent on their stability, circulation time, access and bioavailability to disease sites, and their safety profile. This review covers preclinical and clinical inorganic-nanoparticle based nanomaterial utilized for cancer imaging and therapeutics. A special emphasis is put on the rational design to develop non-toxic/safe inorganic nanoparticle constructs to increase their viability as translatable nanomedicine for cancer therapies.

Nano-sulforaphane attenuates PhIP-induced early abnormal embryonic neuro-development

BACKGROUND

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyrimidine (PhIP), one of the most abundant heterocyclic aromatic amines (HAA) formed by cooking meat at high temperatures, may modify humans and rodents through the metabolic process prior to affecting nervous system development. In humans and rodents may be modified by metabolic processes and then affecting nervous system development.

METHODS

In this paper, PhIP was used to prepare a chicken embryo model with abnormal embryonic nervous system defects. Sulforaphane (SFN) is a derivative of a glucosinolate, which is abundant in cruciferous vegetables, and can pass through the placental barrier. Moreover, SFN has antioxidant and anti-apoptotic functions and is considered as a bioactive antioxidant with significant neuroprotective effects. Nano-sulforaphane (Nano-SFN, sulforaphane nanoparticles) was prepared by self-assembly using biocompatible, biodegradable methoxy polyethylene glycol 5000-b-polyglutamic acid 10,000 (mPEG5K-PGA10K) as the substrate, to explore the new application of Nano-SFN and its modified compounds as leading compounds in protecting against the abnormal development of the embryonic nervous system.

RESULTS

The results show that Nano-SFN could protect against PhIP-induced central nervous system (CNS, derived from neural tube) and peripheral nervous system (PNS, derived from neural crest cells, NCCs) defects and neural tube defects (NTDs), and increase the embryo survival rate.

CONCLUSIONS

This study indicates that Nano-SFN can effectively alleviate the developmental defects of embryonic nervous system induced by PhIP in the microenvironment and has a protective effect on embryonic development. It not only helps with expanding the application of SFN and improving its medicinal value, but also provides a possibility of SFN being developed as a novel drug for neuroprotection.

Tuning the Topological Landscape of DNA-Cyclodextrin Nanocomplexes by Molecular Design

Original molecular vectors that ensure broad flexibility to tune the shape and surface properties of plasmid DNA (pDNA) condensates are reported herein. The prototypic design involves a cyclodextrin (CD) platform bearing a polycationic cluster at the primary face and a doubly linked aromatic module bridging two consecutive monosaccharide units at the secondary face that behaves as a topology-encoding element. Subtle differences at the molecular level then translate into disparate morphologies at the nanoscale, including rods, worms, toroids, globules, ellipsoids, and spheroids. In vitro evaluation of the transfection capabilities revealed marked selectivity differences as a function of nanocomplex morphology. Remarkably high transfection efficiencies were associated with ellipsoidal or spherical shapes with a lamellar internal arrangement of pDNA chains and CD bilayers. Computational studies support that the stability of such supramolecular edifices is directly related to the tendency of the molecular vector to form noncovalent dimers upon DNA templating. Because the stability of the dimers depends on the protonation state of the polycationic clusters, the coaggregates display pH responsiveness, which facilitates endosomal escape and timely DNA release, a key step in successful transfection. The results provide a versatile strategy for the construction of fully synthetic and perfectly monodisperse nonviral gene delivery systems uniquely suited for optimization schemes.

Click Synthesis of Size- and Shape-Tunable Star Polymers with Functional Macrocyclic Cores for Synergistic DNA Complexation and Delivery

The architectural perfection and multivalency of dendrimers have made them useful for biodelivery via peripheral functionalization and the adjustment of dendrimer generations. Modulation of the core-forming and internal matrix-forming structures offers virtually unlimited opportunities for further optimization, but only in a few cases this has been made compatible with strict diastereomeric purity over molecularly diverse series, low toxicity, and limited synthetic effort. Fully regular star polymers built on biocompatible macrocyclic platforms, such as hyperbranched cyclodextrins, offer advantages in terms of facile synthesis and flexible compositions, but core elaboration in terms of shape and function becomes problematic. Here we report the synthesis and characterization of star polymers consisting of functional trehalose-based macrocyclic cores (cyclotrehalans, CTs) and aminothiourea dendron arms, which can be efficiently synthesized from sequential click reactions of orthogonal monomers, display no cytotoxicity, and efficiently complex and deliver plasmid DNA in vitro and in vivo. When compared with some commercial cationic dendrimers or polymers, the new CT-scaffolded star polymers show better transfection efficiencies in several cell lines and structure-dependent cell selectivity patterns. Notably, the CT core could be predefined to exert Zn(II) complexing or molecular inclusion capabilities, which has been exploited to synergistically boost cell transfection by orders of magnitude and modulate the organ tropism in vivo.

Tailoring Viruslike Mesoporous FeSe2 Hedgehogs for Controlled Drug Delivery and Synergistic Tumor Suppression

To enhance affinity to their hosts, many organisms have evolved to be spiky. This strategy has been inspiring in many fields, but in drug delivery, the feasibility has not yet been extensively explored due to the lack of suitable nanocarriers. Herein, viruslike mesoporous FeSe₂ hedgehogs with exceptional photothermal and catalytic performances have been tailored and explored for synergistic tumor therapy. The viruslike topology makes these hedgehogs highly prone to be internalized by cells. By uploading doxorubicin (Dox) into the hollow spikes and encapsulating the hedgehogs with photothermal-meltable gelatin, controlled surface morphology transition from quasi-spherical to spiky and accompanied Dox release have been achieved, with the assistance of the strong photothermal effect of FeSe₂ hedgehogs. These integrated features allow specific and controlled drug delivery, leading to synergistic tumor suppression and immunogenic tumor cell death. These results provide new insights into the tailoring of drug carriers relying on their intrinsic physical features.

Effect of side-chain length on solute encapsulation by amphiphilic heterografted brush copolymers

Anisotropic nanomaterials are non-spherical structures that possess unique shape-dependent physicochemical properties and functionalities. Inspired by the abundance of filamentous entities in nature, cylindrical nanostructures have gained significant attention due to their unique performance. Herein, we discuss the effect of side-chain length on the encapsulation properties of amphiphilic heterografted bottlebrushes. We observed that by grafting a long hydrophilic block to the double-brush, we were able to restrict solute-induced conformational changes, thus producing drug-loaded anisotropic carriers. Unimolecular encapsulation in brushes was solute-dependent as shown here for probucol and rose bengal lactone. Stabilization with an amphiphilic diblock copolymer-consisting of the same type of blocks as those comprising the heterografted brush-served to explain the solute-dependent behavior observed for brushes, suggesting that solutes with a higher propensity to nucleation could be more effectively stabilized by the anisotropic carrier in a unimolecular worm-like construct.

Rapid and sensitive quantification of cell-associated multi-walled carbon nanotubes

Evaluating nanomaterial uptake and association by cells is relevant for in vitro studies related to safe-by-design approaches, nanomedicine or applications in photothermal therapy. However, standard analytical techniques are time-consuming, involve complex sample preparation or include labelling of the investigated sample system with e.g. fluorescent dyes. Here, we explore lock-in thermography to analyse and compare the association trends of epithelial cells, mesothelial cells, and macrophages exposed to gold nanoparticles and multi-walled carbon nanotubes over 24 h. The presence of nanomaterials in the cells was confirmed by dark field and transmission electron microscopy. The results obtained by lock-in thermography for gold nanoparticles were validated with inductively coupled plasma optical emission spectrometry; with data collected showing a good agreement between both techniques. Furthermore, we demonstrate the detection and quantification of carbon nanotube-cell association in a straightforward, non-destructive, and non-intrusive manner without the need to label the carbon nanotubes. Our results display the first approach in utilizing thermography to assess the carbon nanotube amount in cellular environments.

Dual Role of Doxorubicin for Photopolymerization and Therapy

In this study, we report dual roles for doxorubicin (DOX), which can serve as an antitumor drug as well as a cocatalyst for a photoliving radical polymerization. DOX enhances the polymerization rates of a broad range of monomers, including acrylamide, acrylate, and methacrylates, allowing for high monomer conversion and well-defined molecular weights under irradiation with a blue light-emitting diode light (λ_max = 485 nm, 2.2 mW/cm²). Utilizing this property, the photopolymerization of N,N-diethylacrylamide was performed in the presence of a poly(oligo(ethylene glycol) methyl ether acrylate) macroreversible addition-fragmentation chain transfer (macroRAFT) agent to prepare polymeric nanoparticles via aqueous polymerization-induced self-assembly (PISA). By varying the monomer:macroRAFT ratio, spherical polymeric nanoparticles of various diameters could be produced. Most notably, DOX was successfully encapsulated into the hydrophobic core of nanoparticles during the PISA process. The DOX-loaded nanoparticles were effectively uptaken into tumor cells and significantly inhibited the proliferation of tumor cells, demonstrating that the DOX bioactivity was not affected by the polymerization reaction.

The Influence of Nanoparticle Properties on Oral Bioavailability of Drugs

Oral administration has been the most common therapeutic regimen in various diseases because of its high safety, convenience, lower costs, and high compliance of patients. However, susceptible in hostile gastrointestinal (GI) environment, many drugs show poor permeability across GI tract mucus and intestinal epithelium with poor oral absorption and limited therapeutic efficacy. In recent years, nanoparticulate drug delivery systems (NDDS) have become a hot research spot because of their unique advantages including protecting drug from premature degrading and interacting with the physiological environment, increasing intracellular penetration, and enhancing drug absorption. However, a slight change in physicochemistry of nanoparticles can significantly impact their interaction with biological pathways and alter the oral bioavailability of drugs. Hence, this review focuses on the factors affecting oral bioavailability from two aspects. On the one hand, the factors are the biochemical and physiological barriers in oral drugs delivery. On the other hand, the factors are the nanoparticle properties including size, surface properties, and shape of nanoparticles.

Impacts of particle size on the cytotoxicity, cellular internalization, pharmacokinetics and biodistribution of betulinic acid nanosuspensions in combined chemotherapy

To evaluate the effect of particle size on the cellular internalization, tissue distribution, and bioavailability of betulinic acid nanosuspensions (BA/NSs) and further investigate the combined effect of BA/NSs and Taxol® on breast cancer, BA/NSs with different particle sizes (160 nm, 400 nm, and 700 nm) were prepared by an efficient universal green technology. The use of BA/NS (160 nm) was more likely to increase the BA release rate and enhance bioavailability compared with the use of larger size particles. BA/NSs were internalized by 4T1 cells in different ways, including clathrin-mediated endocytosis, caveolae-mediated endocytosis, and macropinocytosis. For the 4T1 orthotopic tumor model, BA/NS (160 nm) showed a tendency to accumulate at a higher level in tumor tissue. Moreover, combination therapy with BA/NSs and Taxol® showed remarkable potential to enhance antitumor activity in vitro and in vivo. The cytotoxicity and apoptotic ability of the different preparations decreased in the following order: BA/NS (160 nm) + Taxol®, BA/NS (400 nm) + Taxol®, and BA/NS (700 nm) + Taxol®. The tumor inhibition rates of BA/NSs (160 nm, 400 nm, and 700 nm) combined with Taxol® were 2.35-, 1.74- and 1.12-fold higher than that of free BA, respectively. The combined chemotherapy showed good safety, indicating that it had the effect of enhancing treatment and reducing toxicity.

Gold nanoparticles against respiratory diseases: oncogenic and viral pathogens review

Nanoscale size-dependent properties give nanomaterials unique specifications that are robust in many applications of human medicine. Gold nanoparticles (AuNPs) have recently gained attention because of their unique optical, physical and electrical properties. AuNPs increase the efficacy of biomedical applications in diagnostic treatments for infectious diseases, by targeting or labeling target cells/bioactive compounds. However, it is imperative to develop the regimens for more accurate diagnostic tools, preventive care and effective therapy. Our critical and comprehensive review presents emerging avenues of molecular diagnostics as well as therapeutics translated into clinical approaches. This manuscript critically reviews the rampant future of AuNPs in the diagnosis and treatment of the most important diseases, such as cancer and viruses of respiratory system.