Adsorption of Glycine on TiO2 in Water from On-the-fly Free-Energy Calculations and In Situ Electrochemical Impedance Spectroscopy

We report here an experimental-computational study of hydrated TiO2 anatase nanoparticles interacting with glycine, where we obtain quantitative agreement of the measured adsorption free energies. Ab initio simulations are performed within the tight binding and density functional theory in combination with enhanced free-energy sampling techniques, which exploit the thermodynamic integration of the unbiased mean forces collected on-the-fly along the molecular dynamics trajectories. The experiments adopt a new and efficient setup for electrochemical impedance spectroscopy measurements based on portable screen-printed gold electrodes, which allows fast and in situ signal assessment. The measured adsorption free energy is -30 kJ/mol (both from experiment and calculation), with preferential interaction of the charged NH3+ group which strongly adsorbs on the TiO2 bridging oxygens. This highlights the importance of the terminal amino groups in the adsorption mechanism of amino acids on hydrated metal oxides. The excellent agreement between computation and experiment for this amino acid opens the doors to the exploration of the interaction free energies for other moderately complex bionano systems.

SciRAPnano: a pragmatic and harmonized approach for quality evaluation of in vitro toxicity data to support risk assessment of nanomaterials

Large amounts of nanotoxicity data from alternative non-animal (in vitro) test methods have been generated, but there is a lack of harmonized quality evaluation approaches for these types of data. Tools for scientifically sound and structured evaluation of the reliability and relevance of in vitro toxicity data to effectively inform regulatory hazard assessment of nanomaterials (NMs), are needed. Here, we present the development of a pragmatic approach to facilitate such evaluation. The tool was developed based on the Science in Risk Assessment and Policy (SciRAP) tool currently applicable to quality evaluation of chemical toxicity studies. The approach taken to develop the tool, referred to as SciRAPnano, included refinement of the original SciRAP in vitro tool through implementation of identified NM-relevant criteria, and further refined based on a set of case studies involving evaluation of 11 studies investigating in vitro toxicity of nano-sized titanium dioxide. Parameters considered cover key physicochemical properties as well as assay-specific aspects that impact NM toxicity, including NM interference with test methods and NM transformation. The final SciRAPnano tool contains 38 criteria for reporting quality, 19 criteria for methodological quality, and 4 guidance items to evaluate relevance. The approach covers essential parameters for pragmatic and harmonized evaluation of NM in vitro toxicity studies and allows for structured use of in vitro data in regulatory hazard assessment of NMs, including transparency on data quality.

PEGylated Strontium Sulfite Nanoparticles with Spontaneously Formed Surface-Embedded Protein Corona Restrict Off-Target Distribution and Accelerate Breast Tumour-Selective Delivery of siRNA

As transporters of RNAi therapeutics in preclinical and clinical studies, the application of nanoparticles is often hindered by their susceptibility to opsonin-mediated clearance, poor biological stability, ineffectual targeting, and undesirable effects on healthy cells. Prolonging the blood circulation time while minimizing the off-target distribution and associated toxicity is indispensable for the establishment of a clinically viable delivery system for therapeutic small interfering RNAs (siRNAs). Herein, we report a scalable and straightforward approach to fabricate non-toxic and biodegradable pH-responsive strontium sulfite nanoparticles (SSNs) wrapped with a hydrophilic coating material, biotinylated PEG to lessen unforeseen biological interactions. Surface functionalization of SSNs with PEG led to the generation of small and uniformly distributed particles with a significant affinity towards siRNAs and augmented internalization into breast cancer cells. A triple quadrupole liquid chromatography-mass spectrometry (LC-MS) was deployed to identify the proteins entrapped onto the SSNs, with the help of SwissProt.Mus_musculus database. The results demonstrated the reduction of opsonin proteins adsorption owing to the stealth effect of PEG. The distribution of PEGylated SSNs in mice after 4 h and 24 h of intravenous administration in breast tumour-bearing mice was found to be significantly less to the organs of the reticuloendothelial system (RES) and augmented accumulation in the tumour region. The anti-EGFR siRNA-loaded PEG-SSNs exerted a significant inhibitory effect on tumour development in the murine breast cancer model without any significant toxicity to healthy tissues. Therefore, PEGylated SSNs open up a new avenue for tumour-selective efficient delivery of siRNAs in managing breast cancer.

Protective Effect of Indomethacin-loaded Polymeric Nanoparticles Against Oxidative Stress-Induced Cytotoxicity in Human Breast Adenocarcinoma Cell Model

Introduction: Anti-inflammatory drugs are being utilized to treat cancer because of its inflammatory microenvironment. Objective: The objective of this study is to investigate the antioxidant potential of indomethacin and its genotoxicity, since free or loaded in polymeric nanocapsules using MCF-7 (human breast cancer) cells as an in vitro model. Method: Development of indomethacin-loaded polyepsiloncaprolactone (PCL) nanocapsules by interfacial deposition method. It is characterized by pH determination by potentiometer, mean diameter and polydispersity index by dynamic light scattering; zeta potential by electrophoretic mobility; encapsulation efficacy by high performance liquid chromatography method; corona effect formation; 2ʹ,7ʹ-dichlorofluorescin diacetate (DCFH-DA) method by spectrofluorimetric assay; nitric oxide (NO) determination by spectrophotometric and genotoxicity assay by plasmid DNA cleavage method. Results: The results showed a mild acidic pH (4.78 ± 0.10), sizes around 200 nm and PDI<0.2 with a zeta potential around -20 mV and encapsulation efficiency of 99% (1 mg mL-1), showing a dose-dependent corona formation profile in 24h incubation. Conclusion: DCFH-DA assay showed no production of reactive oxygen species (ROS) while NO determination showed that Ind-OH-NC from 26.7 to 100 μM increased reactive nitrogen species (RNS), demonstrating antioxidant potential against MCF-7 cells. No sample at the concentrations evaluated induced DNA cleavage, being considered a safe treatment.

Where Is Nano Today and Where Is It Headed? A Review of Nanomedicine and the Dilemma of Nanotoxicology

Worldwide nanotechnology development and application have fueled many scientific advances, but technophilic expectations and technophobic demands must be counterbalanced in parallel. Some of the burning issues today are the following: (1) Where is nano today? (2) How good are the communication and investment networks between academia/research and governments? (3) Is there any spotlight application for nanotechnology? Nanomedicine is a particular arm of nanotechnology within the healthcare landscape, focused on diagnosis, treatment, and monitoring of emerging (such as coronavirus disease 2019, COVID-19) and contemporary (including diabetes, cardiovascular diseases, neurodegenerative disorders, and cancer) diseases. However, it may only represent the bright side of the coin. In fact, in the recent past, the concept of nanotoxicology has emerged to address the dark shadows of nanomedicine. The nanomedicine field requires more nanotoxicological studies to identify undesirable effects and guarantee safety. Here, we provide an overall perspective on nanomedicine and nanotoxicology as central pieces of the giant puzzle of nanotechnology. First, the impact of nanotechnology on education and research is highlighted, followed by market trends and scientific output tendencies. In the next section, the nanomedicine and nanotoxicology dilemma is addressed through the interplay of in silico, in vitro, and in vivo models with the support of omics and microfluidic approaches. Lastly, a reflection on the regulatory issues and clinical trials is provided. Finally, some conclusions and future perspectives are proposed for a clearer and safer translation of nanomedicines from the bench to the bedside.

Understanding Nanomaterial-Liver Interactions to Facilitate the Development of Safer Nanoapplications

Nanomaterials (NMs) are widely used in commercial and medical products, such as cosmetics, vaccines, and drug carriers. Exposure to NMs via various routes such as dermal, inhalation, and ingestion has been shown to gain access to the systemic circulation, resulting in the accumulation of NMs in the liver. The unique organ structures and blood flow features facilitate the liver sequestration of NMs, which may cause adverse effects in the liver. Currently, most in vivo studies are focused on NMs accumulation at the organ level and evaluation of the gross changes in liver structure and functions, however, cell-type-specific uptake and responses, as well as the molecular mechanisms at cellular levels leading to effects at organ levels are lagging. Herein, the authors systematically review diverse interactions of NMs with the liver, specifically on major liver cell types including Kupffer cells (KCs), liver sinusoidal endothelial cells (LSECs), hepatic stellate cells (HSCs), and hepatocytes as well as the detailed molecular mechanisms involved. In addition, the knowledge gained on nano-liver interactions that can facilitate the development of safer nanoproducts and nanomedicine is also reviewed.

Impact of Protein Corona on the Biological Identity of Nanomedicine: Understanding the Fate of Nanomaterials in the Biological Milieu

Nanoparticles (NPs) in contact with a biological medium are rapidly comprehended by a number of protein molecules resulting in the formation of an NP-protein complex called protein corona (PC). The cell sees the protein-coated NPs as the synthetic identity is masked by protein surfacing. The PC formation ultimately has a substantial impact on various biological processes including drug release, drug targeting, cell recognition, biodistribution, cellular uptake, and therapeutic efficacy. Further, the composition of PC is largely influenced by the physico-chemical properties of NPs viz. the size, shape, surface charge, and surface chemistry in the biological milieu. However, the change in the biological responses of the new substrate depends on the quantity of protein access by the NPs. The PC-layered NPs act as new biological entities and are recognized as different targeting agents for the receptor-mediated ingress of therapeutics in the biological cells. The corona-enveloped NPs have both pros and cons in the biological system. The review provides a brief insight into the impact of biomolecules on nanomaterials carrying cargos and their ultimate fate in the biological milieu.

The differences of the impact of a lipid and protein corona on the colloidal stability, toxicity, and degradation behavior of iron oxide nanoparticles

AIM

In this study, the influence of a serum albumin (SA) and human plasma (HP) derived protein- and lipid molecule corona on the toxicity and biodegradability of different iron oxide nanoparticles (IONP) was investigated.

METHODS

IONP were synthesized and physicochemically characterized regarding size, charge, and colloidal stability. The adsorbed proteins were quantified and separated by gel electrophoresis. Adsorbed lipids were profiled by ultraperformance liquid chromatography-ESI-tandem mass spectrometry. The biocompatibility was investigated using isolated erythrocytes and a shell-less hen's egg model. The biodegradability was assessed by iron release studies in artificial body fluids.

RESULTS

The adsorption patterns of proteins and lipids varied depending on the surface characteristics of the IONP like charge and hydrophobicity. The biomolecule corona modified IONP displayed favorable colloidal stability and toxicological profile compared to IONP without biomolecule coronas, reducing erythrocyte aggregation and hemolysis in vitro as well as the corresponding effects ex ovo/in vivo. The coronas decreased the degradation speed of all tested IONP compared to bare particles, but, whereas all IONP degraded at the same rate for the SA corona, substantial differences were evident for IONP with HP-derived corona depending on the lipid adsorption profile.

CONCLUSION

In this study the impact of the proteins and lipids in the biomolecule corona on the entire IONP application cycle from the injection process to the degradation was demonstrated.

The pharmacology of plant virus nanoparticles

The application of nanoparticles for medical purposes has made enormous strides in providing new solutions to health problems. The observation that plant virus-based nanoparticles (VNPs) can be repurposed and engineered as smart bio-vehicles for targeted drug delivery and imaging has launched extensive research for improving the therapeutic and diagnostic management of various diseases. There is evidence that VNPs are promising high value nanocarriers with potential for translational development. This is mainly due to their unique features, encompassing structural uniformity, ease of manufacture and functionalization by means of expression, chemical biology and self-assembly. While the development pipeline is moving rapidly, with many reports focusing on engineering and manufacturing aspects to tailor the properties and efficacy of VNPs, fewer studies have focused on gaining insights into the nanotoxicity of this novel platform nanotechnology. Herein, we discuss the pharmacology of VNPs as a function of formulation and route of administration. VNPs are reviewed in the context of their application as therapeutic adjuvants or nanocarrier excipients to initiate, enhance, attenuate or impede the formulation's toxicity. The summary of the data however also underlines the need for meticulous VNP structure-nanotoxicity studies to improve our understanding of their in vivo fates and pharmacological profiles to pave the way for translation of VNP-based formulations into the clinical setting.

Effects of Surface Protein Adsorption on the Distribution and Retention of Intratumorally Administered Gold Nanoparticles

The heterogeneous distribution of delivery or treatment modalities within the tumor mass is a crucial limiting factor for a vast range of theranostic applications. Understanding the interactions between a nanomaterial and the tumor microenvironment will help to overcome challenges associated with tumor heterogeneity, as well as the clinical translation of nanotheranostic materials. This study aims to evaluate the influence of protein surface adsorption on gold nanoparticle (GNP) biodistribution using high-resolution computed tomography (CT) preclinical imaging in C57BL/6 mice harboring Lewis lung carcinoma (LLC) tumors. LLC provides a valuable model for study due to its highly heterogenous nature, which makes drug delivery to the tumor challenging. By controlling the adsorption of proteins on the GNP surface, we hypothesize that we can influence the intratumoral distribution pattern and particle retention. We performed an in vitro study to evaluate the uptake of GNPs by LLC cells and an in vivo study to assess and quantify the GNP biodistribution by injecting concentrated GNPs citrate-stabilized or passivated with bovine serum albumin (BSA) intratumorally into LLC solid tumors. Quantitative CT and inductively coupled plasma optical emission spectrometry (ICP-OES) results both confirm the presence of particles in the tumor 9 days post-injection (n = 8 mice/group). A significant difference is highlighted between citrate-GNP and BSA-GNP groups (** p < 0.005, Tukey's multiple comparisons test), confirming that the protein corona of GNPs modifies intratumoral distribution and retention of the particles. In conclusion, our investigations show that the surface passivation of GNPs influences the mechanism of cellular uptake and intratumoral distribution in vivo, highlighting the spatial heterogeneity of the solid tumor.

NanoSolveIT Project: Driving nanoinformatics research to develop innovative and integrated tools for in silico nanosafety assessment

Nanotechnology has enabled the discovery of a multitude of novel materials exhibiting unique physicochemical (PChem) properties compared to their bulk analogues. These properties have led to a rapidly increasing range of commercial applications; this, however, may come at a cost, if an association to long-term health and environmental risks is discovered or even just perceived. Many nanomaterials (NMs) have not yet had their potential adverse biological effects fully assessed, due to costs and time constraints associated with the experimental assessment, frequently involving animals. Here, the available NM libraries are analyzed for their suitability for integration with novel nanoinformatics approaches and for the development of NM specific Integrated Approaches to Testing and Assessment (IATA) for human and environmental risk assessment, all within the NanoSolveIT cloud-platform. These established and well-characterized NM libraries (e.g. NanoMILE, NanoSolutions, NANoREG, NanoFASE, caLIBRAte, NanoTEST and the Nanomaterial Registry (>2000 NMs)) contain physicochemical characterization data as well as data for several relevant biological endpoints, assessed in part using harmonized Organisation for Economic Co-operation and Development (OECD) methods and test guidelines. Integration of such extensive NM information sources with the latest nanoinformatics methods will allow NanoSolveIT to model the relationships between NM structure (morphology), properties and their adverse effects and to predict the effects of other NMs for which less data is available. The project specifically addresses the needs of regulatory agencies and industry to effectively and rapidly evaluate the exposure, NM hazard and risk from nanomaterials and nano-enabled products, enabling implementation of computational 'safe-by-design' approaches to facilitate NM commercialization.

The biomolecular corona of gold nanoparticles in a controlled microfluidic environment

Nanoparticles (NPs) exposed to biological media are coated by proteins and other biomolecules forming a biomolecular corona (BC) on the particle surface. Recent studies have shown that shear stress as that created by laminar fluid flow generates more complex coronas with systematic changes in composition with respect to counterparts formed under static incubation. However, in most studies reported so far, dynamic environments have been produced by peristaltic pumps and comparing experimental results appears challenging. On the other side, generating shear stress by microfluidic devices could help to remove user variability and ensure better reproducibility of experimental data. This study was therefore aimed at exploring formation of NP-BC in a microfluidic environment. To this end, 100 nm gold nanoparticles and human plasma (HP) were used as models for nano-formulation and biological medium. We injected gold nanoparticles and HP in each of the islets of a remote-controlled microfluidic cartridge. Static incubation was used as a reference. BC-decorated NPs were thoroughly characterized by dynamic light scattering (DLS), micro-electrophoresis (ME), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) and nano-liquid chromatography tandem mass spectrometry (nano-LC MS/MS). By varying the incubation time from 30 s to 2.5 min we demonstrate that BC is already determined by the earliest exposure time point and does not appreciably evolve in time. DLS and ME results demonstrate that the BC formed in a microfluidic chip is thicker and more negatively charged than its counterpart formed under static incubation. SDS-PAGE and nano-LC MS/MS revealed that the incubation procedure had a major effect on BC composition. As an example, immunoglobulins are the most abundant plasma proteins of the BC generated in a microfluidic environment (relative protein abundance ∼30%), while tissue leakage proteins (relative protein abundance ∼26%) are the most enriched proteins when the BC is formed upon static incubation. Potential implications in emerging biomedical research arenas are discussed.

Toxicity of carbon-based nanomaterials: Reviewing recent reports in medical and biological systems

Application of nanomaterials in our daily life is increasing, day in day out and concerns have raised about their toxicity for human and other organisms. In this manner, carbon-based nanomaterials have been applied to different products due to their unique physicochemical, electrical, mechanical properties, and biological compatibility. But, there are several reports about the negative effects of these materials on biological systems and cellular compartments. This review article describes the various types of carbon-based nanomaterials and methods that use for determining these toxic effects that are reported recently in the papers. Then, extensively discussed the toxic effects of these materials on the human and other living organisms and also their toxicity routs including Neurotoxicity, Hepatotoxicity, Nephrotoxicity, Immunotoxicity, Cardiotoxicity, Genotoxicity and epigenetic toxicity, Dermatotoxicity, and Carcinogenicity.

Tissue distribution of Ag and oxidative stress responses in the freshwater snail Bellamya aeruginosa exposed to sediment-associated Ag nanoparticles

Silver nanoparticles (AgNPs) are among the most widely used engineered nanomaterials and may eventually accumulate in sediments. Limited information is currently available regarding the toxicity, bioaccumulation and distribution of sediment-associated AgNPs in aquatic organisms. In the present study, a freshwater snail Bellamya aeruginosa was exposed via sediment to commercial Ag particles of four nominal sizes: 20 nm (AgNPs-20), 40 nm (AgNPs-40), 80 nm (AgNPs-80), and < 10 μm (bulk Ag), and to silver nitrate at sub-lethal concentrations (1, 10 and 100 μg Ag/g sediment). Ag burden and biomarkers of oxidative stress were assessed in different tissues of B. aeruginosa: hepatopancreas, gonad, foot and digestive tracts. All five Ag types were available for uptake by B. aeruginosa when spiked into sediment, and Ag accumulation in different tissues presented the following pattern: hepatopancreas > gonad ≈ digestive tracts > foot. Snails accumulated higher levels of Ag from aqueous Ag than from particulate Ag. In contrast, AgNPs-40 and AgNPs-80 treatments occasionally induced higher oxidative stress than aqueous Ag, indicating the significant role of nanoparticle itself in exerting toxicity. Size-dependent toxicity of AgNPs in sediment was also found, with AgNPs-20 showing lower toxicity than other Ag particles. Overall, this study demonstrated that the toxicity of sediment-associated AgNPs to B. aeruginosa varies with size and differs from aqueous Ag.

How Entanglement of Different Physicochemical Properties Complicates the Prediction of in Vitro and in Vivo Interactions of Gold Nanoparticles

The physicochemical properties of a set of 21 different gold nanoparticles (spherical and rod-shaped nanoparticles (NPs) of different diameters with three different surface coatings) were studied. Protein corona formation, in vitro uptake, effect on cell viability and proliferation, and in vivo biodistribution of these NPs were determined. The relation of the results of the different NPs was analyzed by hierarchical cluster analysis, which will tell which NPs have the most similar physicochemical properties and biological effects, without having to specify individual physicochemical parameters. The results show that the physicochemical properties of gold nanoparticles (Au NPs) are mainly accounted for by their hydrodynamic diameter and their zeta-potential. The formation of the protein corona is determined by the pH-dependence of their zeta-potential. While several reports found that in vitro uptake and in vivo biodistribution of NPs are correlated to individual physicochemical parameters, e. g., size, shape, or surface chemistry, such direct dependence in the investigated multidimensional set of NPs was not found in our study. This most likely is due to entanglement of the different parameters, which complicates the prediction of the biological effect of NPs in case multiple physicochemical properties are simultaneously varied. The in vitro uptake and in vivo biodistribution of NPs seem to be not directly driven by the protein corona, but the physicochemical properties determine as well the corona as they influence in vitro/ in vivo behaviors, and thus the effect of the protein corona would be rather indirect.

PEGylation of Carbonate Apatite Nanoparticles Prevents Opsonin Binding and Enhances Tumor Accumulation of Gemcitabine

pH sensitives carbonate apatite (CA) has emerged as a targeted delivery vehicle for chemotherapeutics agent with tremendous potential to increase the effectivity of breast cancer treatment. The major challenge for intravenous delivery of drug-incorporated nanoparticles is their rapid opsonization, resulting in accumulation within the organs of reticuloendothelial system, such as liver and spleen. Therefore, surface modification by polyethylene glycol was implemented to improve the half-life of drug-particle complexes and enhance their uptake by target tissues. A simple, rapid, and sensitive triple quadrupole liquid chromatography-mass spectrometry method was developed and validated for quantification of gemcitabine in plasma, various organs and tumor tissues of mice with breast carcinoma, whereas sodium dodecyl sulfate-polyacrylamide gel electrophoresis, quadrupole-time of flight liquid chromatography-mass spectrometry and analysis by SwissProt.Mus_musculus database were performed for protein separation, identification, and homology search by comparing the de novo sequence tag. PEGylated CA exhibited almost 6-fold increase in gemcitabine accumulation in tumor with significant reduction in other organs within 1 h of intravenous administration, compared to free drug. In addition, plasma drug amount was found to be higher in PEGylated particles, implying their role in prolonging blood circulation time of particle-bound gemcitabine. Investigation of protein corona composition demonstrated notable reduction in opsonin interactions after PEGylation of CA particles. Overall, the results indicate that the composition and dynamics of protein corona subjected to alteration by PEGylation play crucial roles in affecting successful nanoparticle-based targeted delivery of a cytotoxic drug.

Undiluted human whole blood uric acid detection using a graphitized mesoporous carbon modified electrode: a potential tool for clinical point-of-care uric acid diagnosis

Direct sensing of uric acid (UA) in an undiluted whole blood sample is reported here taking human whole blood as an analyte and a self-supporting electrolyte. Among various solid electrodes (Pt, Au, GCE, and GCE/Nafion) and carbon nanomaterials (carbon nanofibers, graphene oxide, graphite nanopowder, graphitized mesoporous carbon (GMC), single-walled carbon nanotubes, and multiwalled carbon nanotubes) tested, a GMC-modified glassy carbon electrode, designated as GCE/GMC, showed a remarkable response towards direct electrochemical oxidation of blood uric acid at ∼0.25 V vs. Ag/AgCl, unlike the poor and/or feeble current signals with the other unmodified and modified electrodes. It is plausible that the mesoporous nature of the GMC favours the formation of a blood-GMC bio-corona through internalization and provides straight access to blood-matrixed uric acid. Furthermore, the effects of the scan rate and interference with various biochemicals on the GCE/GMC were analysed. The electrochemical oxidation reaction is found to be diffusion controlled in nature and there is no interference from common biochemicals like ascorbic acid, glucose, tryptophan, H2O2, xanthine, hypoxanthine, cysteine, nitrate, nitrite, and sulfide in blood. Real blood UA sample analysis was demonstrated with comparable UA analysis results from the clinical measurement.

Clinically approved liposomal nanomedicines: lessons learned from the biomolecular corona

Nowadays, liposomes are the most successful drug delivery systems with a dozen drug products available in the clinic. Grafting poly-(ethylene glycol) (PEG) onto the liposome surface prevents protein binding thus prolonging blood circulation, while synthetic modification of the terminal PEG molecule with ligands (e.g. monoclonal antibodies and peptides) should promote selective accumulation in the tumor region with respect to healthy tissues. However, despite big efforts, advances have not outgrown the development stage and just a few targeted liposomal drugs are commercially available. The latest studies have clarified that following exposure to physiological environments liposomes are covered by a biomolecular corona (BC). Main factors shaping the BC are the liposomes' physicochemical properties (i.e. size, surface charge and lipid composition), the biological fluid (e.g. plasma of healthy volunteers vs. plasma of cancer patients) and environmental factors (e.g. temperature). Combining the most recent evidence reported in the literature, herein we suggest that the liposome-BC could act as a personalized "endogenous trigger" affecting off-target interactions and controlling the indication for disease of clinically approved formulations. In this Opinion paper, we suggest that a better understanding of the liposome-BC together with improvements in mapping corona proteins will open the fascinating possibility to manipulate the BC by liposome design. This is not an easy task, but it could represent a turning point in the development of novel liposome-based targeting strategies for personalized nanomedicines.

Protein bio-corona: critical issue in immune nanotoxicology

With the expansion of the nanomedicine field, the knowledge focusing on the behavior of nanoparticles in the biological milieu has rapidly escalated. Upon introduction to a complex biological system, nanomaterials dynamically interact with all the encountered biomolecules and form the protein "bio-corona." The decoration with these surface biomolecules endows nanoparticles with new properties. The present review will address updates of the protein bio-corona characteristics as influenced by nanoparticle's physicochemical properties and by the particularities of the encountered biological milieu. Undeniably, bio-corona generation influences the efficacy of the nanodrug and guides the actions of innate and adaptive immunity. Exploiting the dynamic process of protein bio-corona development in combination with the new engineered horizons of drugs linked to nanoparticles could lead to innovative functional nanotherapies. Therefore, bio-medical nanotechnologies should focus on the interactions of nanoparticles with the immune system for both safety and efficacy reasons.

Delivery of cancer therapeutics to extracellular and intracellular targets: Determinants, barriers, challenges and opportunities

Advances in molecular medicine have led to identification of worthy cellular and molecular targets located in extracellular and intracellular compartments. Effectiveness of cancer therapeutics is limited in part by inadequate delivery and transport in tumor interstitium. Parts I and II of this report give an overview on the kinetic processes in delivering therapeutics to their intended targets, the transport barriers in tumor microenvironment and extracellular matrix (TME/ECM), and the experimental approaches to overcome such barriers. Part III discusses new concepts and findings concerning nanoparticle-biocorona complex, including the effects of TME/ECM. Part IV outlines the challenges in animal-to-human translation of cancer nanotherapeutics. Part V provides an overview of the background, current status, and the roles of TME/ECM in immune checkpoint inhibition therapy, the newest cancer treatment modality. Part VI outlines the development and use of multiscale computational modeling to capture the unavoidable tumor heterogeneities, the multiple nonlinear kinetic processes including interstitial and transvascular transport and interactions between cancer therapeutics and TME/ECM, in order to predict the in vivo tumor spatiokinetics of a therapeutic based on experimental in vitro biointerfacial interaction data. Part VII provides perspectives on translational research using quantitative systems pharmacology approaches.