Influence of surface chemistry and morphology of nanoparticles on protein corona formation

Nanomaterials offer promising solutions as drug delivery systems and imaging agents in response to the demand for better therapeutics and diagnostics. However, the limited understanding of the interaction between nanoparticles and biological entities is currently hampering the development of new systems and their applications in clinical settings. Proteins and lipids in biological fluids are known to complex with nanoparticles to form a “biomolecular corona”. This has been shown to affect particles' morphology and behavior in biological systems and their interactions with cells. Hence, understanding how nanomaterials' physicochemical properties affect the formation and composition of this biocorona is a crucial step. This work evaluates existing literature on how morphology (size and shape), and surface chemistry (charge and hydrophobicity) of nanoparticles influence the formation of protein corona. The latest evidence suggest that although surface charge promotes the interaction with proteins and lipids, surface chemistry plays a leading role in determining the affinity of the nanoparticle for biomolecules and, ultimately, the composition of the corona. More recently the study of additional nanoparticles' properties like shape and surface chirality have demonstrated a significant effect on protein corona architecture, providing new tools to tailor biomolecular corona formation. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies. Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials

Bio-Inspired Amphiphilic Block-Copolymers Based on Synthetic Glycopolymer and Poly(Amino Acid) as Potential Drug Delivery Systems

In this work, a method to prepare hybrid amphiphilic block copolymers consisting of biocompatible synthetic glycopolymer with non-degradable backbone and biodegradable poly(amino acid) (PAA) was developed. The glycopolymer, poly(2-deoxy-2-methacrylamido-D-glucose) (PMAG), was synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. Two methods for modifying the terminal dithiobenzoate-group of PMAG was investigated to obtain the macroinitiator bearing a primary aliphatic amino group, which is required for ring-opening polymerization of N-carboxyanhydrides of hydrophobic α-amino acids. The synthesized amphiphilic block copolymers were carefully analyzed using a set of different physico-chemical methods to establish their composition and molecular weight. The developed amphiphilic copolymers tended to self-assemble in nanoparticles of different morphology that depended on the nature of the hydrophobic amino acid present in the copolymer. The hydrodynamic diameter, morphology, and cytotoxicity of polymer particles based on PMAG-b-PAA were evaluated using dynamic light scattering (DLS) and transmission electron microscopy (TEM), as well as CellTiter-Blue (CTB) assay, respectively. The redox-responsive properties of nanoparticles were evaluated in the presence of glutathione taken at different concentrations. Moreover, the encapsulation of paclitaxel into PMAG-b-PAA particles and their cytotoxicity on human lung carcinoma cells (A549) and human breast adenocarcinoma cells (MCF-7) were studied

Thermoresponsive poly-N-isopropylacrylamide nanogels for brain drug delivery

Intravenous drug delivery to brain tissue is a challenge for modern medical research. Nanotechnology offers a promising solution using polymeric nanoparticles that can transport a drug across the blood-brain barrier and release it on demand. A promising candidate for stimulus-induced drug release are poly-N-isopropylacrylamide (pNIPAm) nanogels, which have shown sufficient drug loading capacity and low toxicity for use in brain therapy. PNIPAm nanoparticles exhibit a temperature-dependent phase transition in an aqueous medium - they swell in size at temperatures below the volume phase transition temperature and lose their hydration shell and shrink at temperatures above. These promising characteristics of pNIPAm have led to their extensive research, resulting in several different synthetic methodologies for the preparation of pNIPAm nanoparticles. However, a systematic study of the effect of synthetic parameters on the structure and properties of pNIPAm nanogels is still lacking, which makes it difficult to compare the experimental data on pNIPAm gels obtained by different researchers. This project represents a contribution to the research area that is aiming to understand the effect of synthetic methodology on the morphology and thermoresponsive behaviour of pNIPAm nanogels and determine the benefits of each methodology for creating drug delivery system to the brain. Chapter 1 provides an introduction to the advances in the area of novel nanomaterials as drug delivery vehicles for applications to the brain. Among the different types of nanoparticles, pNIPAm nanogels are indicated as the materials with highest potential and an overview of the various synthetic methodologies for their preparations is discussed. In Chapter 2, the data on the characterisation of the nanoparticles and the comparison of structure and properties of the different nanogels are considered; correlation with the various synthetic methodologies is also attempted. In Chapter 3, the ability of various pNIPAm nanomaterials to load and release retinoic acid, used as model of low molecular weight drugs, was evaluated. In Chapter 4, the overall conclusions of this research project is presented, together with perspectives and future interesting areas of work; this is followed by a detailed section of materials and methods (Chapter 5) and the references

Theoretical-methodical approaches to development of specializations “Artistically-project creation”, “decoratively-applied art”, “Bases of design” at type level of preparation of students 10-11 classes in the system of continuous artistically-project educ

In the article theoretical-methodical approaches are grounded to development of thespecializations “Artistically-project creation”, “Decoratively-applied art”, “Bases of design”at type level of preparation of students 10-11 classes in the system of continuous artisticallyprojecteducation. Systemoobrazuyuschye aspects for the synthesis of maintenance ofeducational industries are certain “Art” and “Technologies” of continuous artisticallyprojecteducation in OUZ and INSTITUTE of higher. Theoretical positions of modernmethodology of continuous artistically-project education at type level from positions offundamental research in Institute of pedagogics of the National academy of pedagogicalsciences of Ukraine are exposed.Key words: fundamental researches; continuous artistically-project education in OUZand INSTITUTE of higher; propedevtyka, doprofyl'nyy and type levels of preparation;specializations: “Artistically-project creation”, “decoratively-applied art”, “Bases ofdesign”; national schools of artistically-project formation of Ukraine is Kiev, Lvov, Kharkov;artistically-industrial schools of Ukraine; artistically-industrial education.</p

Some remarks on new directions in social archaeology of early nomads

The article discusses the interpretational issues of the so-called actor-network theory (ANT) in relation to the archeology of nomadic societies. Based on selected examples, in particular the analysis of clan symbols, the so-called tamga and military organization units (so-called troops), the authors present potential new interpretations of known cultural phenomena in the archeology of the Great Steppe

Systematic Analysis of the Relative Abundance of Polymers Occurring as Microplastics in Freshwaters and Estuaries

Despite growing interest in the environmental impact of microplastics, a standardized characterization method is not available. We carried out a systematic analysis of reliable global data detailing the relative abundance of polymers in freshwaters and estuaries. The polymers were identified according to seven main categories: polyethylene terephthalate, polyethylene, polyvinyl chloride, polypropylene, polystyrene, polyurethane and a final category of miscellaneous plastic. The results show that microplastics comprised of polyvinyl chloride and polyurethane are significantly less abundant than would be expected based on global production, possibly due to their use. This has implications for models of microplastic release into the environment based on production and fate. When analysed by matrix (water, sediment or biota) distinct profiles were obtained for each category. Polyethylene, polypropylene and polystyrene were more abundant in sediment than in biota, while miscellaneous plastics was more frequent in biota. The data suggest that environmental sorting of microplastic particles, influenced by physical, chemical and biological processes, may play a key role in environmental impact, although partitioning among matrices based on density was not realized. The distinct profile of microplastics in biota raises an important question regarding potential selectivity in uptake by organisms, highlighting the priority for more and better-informed laboratory exposure studie

Self-Assembled Nanoparticles Based on Block-Copolymers of Poly(2-Deoxy-2-methacrylamido-d-glucose)/Poly(N-Vinyl Succinamic Acid) with Poly(O-Cholesteryl Methacrylate) for Delivery of Hydrophobic Drugs

The self-assembly of amphiphilic block-copolymers is a convenient way to obtain soft nanomaterials of different morphology and scale. In turn, the use of a biomimetic approach makes it possible to synthesize polymers with fragments similar to natural macromolecules but more resistant to biodegradation. In this study, we synthesized the novel bio-inspired amphiphilic block-copolymers consisting of poly(N-methacrylamido-d-glucose) or poly(N-vinyl succinamic acid) as a hydrophilic fragment and poly(O-cholesteryl methacrylate) as a hydrophobic fragment. Block-copolymers were synthesized by radical addition–fragmentation chain-transfer (RAFT) polymerization using dithiobenzoate or trithiocarbonate chain-transfer agent depending on the first monomer, further forming the hydrophilic block. Both homopolymers and copolymers were characterized by 1H NMR and Fourier transform infrared spectroscopy, as well as thermogravimetric analysis. The obtained copolymers had low dispersity (1.05–1.37) and molecular weights in the range of ~13,000–32,000. The amphiphilic copolymers demonstrated enhanced thermal stability in comparison with hydrophilic precursors. According to dynamic light scattering and nanoparticle tracking analysis, the obtained amphiphilic copolymers were able to self-assemble in aqueous media into nanoparticles with a hydrodynamic diameter of approximately 200 nm. An investigation of nanoparticles by transmission electron microscopy revealed their spherical shape. The obtained nanoparticles did not demonstrate cytotoxicity against human embryonic kidney (HEK293) and bronchial epithelial (BEAS-2B) cells, and they were characterized by a low uptake by macrophages in vitro. Paclitaxel loaded into the developed polymer nanoparticles retained biological activity against lung adenocarcinoma epithelial cells (A549)