In this work a novel method for synthesis of 1,8-dihydroxynaphthalene melanin was presented, as well as the physicochemical properties, molecular structure, and characteristics of the pigment. The proposed synthesis protocol is simple and cost-effective with no enzymes or catalysts needed. The final product is not adsorbed on any surface, since the pigment is the result of autooxidation of 1,8-dihydroxynaphthalene.
View Article and Find Full Text PDFA series of benzothieno[3,2-b]benzothiophene S-oxides has been efficiently synthesized via one- or two-step selective oxidation of benzothieno[3,2-b]benzothiophene (BTBT). These BTBT S-oxides form highly ordered structures that display optical anisotropy, are thermally stable up to temperatures above 210 °C, and do not show phase transitions. They exhibit long excited state lifetimes (0.
View Article and Find Full Text PDFCrystallization-controlled structure and thermal properties of biobased poly(ethylene 2,5-furandicarboxylate) (PEF) were studied. The cold-crystallization temperature controlled the structure and thermal properties of the biobased PEF. The melting was complex and evidenced the presence of a significant fraction of less-stable crystals with a low melting temperature that linearly increased with , which formed already during the early stages of crystallization, together with those melting at a higher temperature.
View Article and Find Full Text PDFThe unique nonparallel chain arrangement in the orthorhombic γ-form lamellae of isotactic polypropylene (iPP) results in the enhancement of the mechanical properties of γ-iPP. Our study aimed at the investigation of the mechanical properties of γ-iPP nanocomposites with 1-5 wt.% multiwall carbon nanotubes (MWCNT) and 5 wt.
View Article and Find Full Text PDFGene therapy presents an innovative approach to the treatment of previously incurable diseases. The advancement of research in the field of nanotechnology has the potential to overcome the current limitations and challenges of conventional therapy methods, and therefore to unlocking the full potential of dendrimers for use in the gene therapy of neurodegenerative disorders. The blood-brain barrier (BBB) poses a significant challenge when delivering therapeutic agents to the central nervous system.
View Article and Find Full Text PDFAmphiphilic triblock copolymers, polyglycidol-polystyrene-polyglycidol (PGL-PS-PGL), were synthesised anionic polymerization starting from the synthesis of a polystyrene macroinitiator with 60 styrene units in the block terminated by ethylene oxide. Poly(ethoxyethyl glycidyl ether) blocks of different lengths were created on both sides of the macroinitiator. By removing the ethoxyethyl blocking groups, PGL-PS-PGL copolymers containing polyglycidol blocks with DP 11, 23, 44 and 63 were received.
View Article and Find Full Text PDF3D printing was used to prepare implantable systems or tablets loaded with dolutegravir to explore their potential as long-acting implantables (LAIs). Our strategy relies on preparing a polylactide (PLA) filament loaded with the anti-HIV drug. Subsequently, 3D printing was performed under conditions that allowed the PLA to be simultaneously melted and the drug encapsulated within the printed strand.
View Article and Find Full Text PDFCotton and poly(ethylene terephthalate) (PET) woven fabrics were coated with graphene oxide (GO) using a padding method and the GO deposited on the fiber surfaces was thermally reduced to impart electrical conductivity to the fabrics. To assist the thermal reduction of GO, quercetin (Q)-a natural flavonoid-was used. To this end, before the reduction, the GO-padded fabrics were immersed in Q solutions in ethanol with different Q concentrations.
View Article and Find Full Text PDFThree different devices: ball mill, hot stage melting, and magic angle spinning (MAS) NMR rotor were used for the preparation of ethenzamide (ET) cocrystals with glutaric acid (GLU), ethylmalonic acid (EMA) and maleic acid (MAL) as coformers. In each case, well-defined binary systems (ET:EMA, ET:GLU, ET:MAL) were obtained. The common features of the two solvent free methods of cocrystal formation (grinding, melting) are presented on the basis of arguments obtained by solid state NMR spectroscopy.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
January 2024
Novel poly(ethylene 2,5-furandicarboxylate) PEF nonwovens were produced by solution electrospinning and further modification. To improve the wettability of the hydrophobic nonwovens with water, they were treated with sodium hydroxide. Cytotoxicity tests carried out with human keratinocytes confirmed that the nonwovens did not have a toxic effect on healthy cells.
View Article and Find Full Text PDFNaturally occurring compounds, such as tannic acid (TA), are perfect for constructing nanohybrids (NHs) with metal ions due to their anticarcinogenic, antimicrobial, and antioxidant properties. To date, the batch methods are the ones in which such NHs were constructed; however, those methods possess many drawbacks, such as low reproducibility or size variations. To overcome this limitation, microfluidic preparation is proposed for NHs construction composed of TA and iron (III).
View Article and Find Full Text PDFPolylactide nonwovens were electrospun from solutions and then crystallized, one in α-form, and another, S-PLA, made of poly(l-lactide) and poly(d-lactide) 1:1 blend, in scPLA crystals with high melting temperature, close to 220 °C. To make the nonwovens electrically conductive, they were coated with multiwall carbon nanotubes (MWCNT) by padding and dip-coating with an aqueous dispersion of MWCNT. The electrical conductivity evidenced the formation of the electrically conductive MWCNT network on the fiber surfaces.
View Article and Find Full Text PDFAssemblies of colloidal polymer particles find various applications in many advanced technologies. However, for every type of application, assemblies with properly tailored properties are needed. Until now, attention has been concentrated on the assemblies composed of spherical particles arranged into so-called perfect colloidal crystals and on complex materials containing mixtures of crystal and disordered phases.
View Article and Find Full Text PDFThe microbiological purity of textiles plays a pivotal role in the use of textiles, especially in hospitals and other medical facilities. Microbiological purity of cotton fabric was achieved by a new disinfection method using tetrabutyloammonium OXONE (TBA-OXONE) before washing. As a result of the disinfection, the cotton fabric became microbiologically pure, despite the markedly decreased washing time with respect to the widely used standard procedure.
View Article and Find Full Text PDFGraphene oxide (GO) was deposited on a cotton fabric and then thermally reduced to reduced graphene oxide (rGO) with the assistance of L-ascorbic acid. The GO reduction imparted electrical conductivity to the fabric and allowed for electrochemical deposition of Ag° particles using cyclic voltammetry. Only the Ag°/rGO composite coating imparted antibacterial properties to the fabric against and .
View Article and Find Full Text PDFIn this paper, an original method of synthesis of Coil-Brush amphiphilic polystyrene-(polyglycidol--polyglycidol) (PS--(PGL--PGL)) block copolymers was developed. The hypothesis that their hydrophilicity and micellization can be controlled by polyglycidol blocks architecture was verified. The research enabled comparison of behavior in water of PS--PGL copolymers and block-brush copolymers PS--(PGL--PGL) with similar composition.
View Article and Find Full Text PDFElectrospun nonwovens of poly(L-lactide) (PLLA) modified with multiwall carbon nanotubes (MWCNT) and linear ladder-like poly(silsesquioxane) with methoxycarbonyl side groups (LPSQ-COOMe) were obtained. MWCNT and LPSQ-COOMe were added to the polymer solution before the electrospinning. In addition, nonwovens of PLLA grafted to modified MWCNT were electrospun.
View Article and Find Full Text PDFThis study was aimed towards the development of a novel microfluidic approach for the preparation of (co)polymeric and hybrid nanoparticles (NPs) composed of (co)polymers/tannic acid (TA) in the microfluidic flow-focusing glass-capillary device. The MiliQ water was used as water phase, whereas the organic phase was composed of poly(ε-caprolactone) (PCL) and poly(trimethylene carbonate) (PTMC) homopolymers and (co)polymers with different proportion of comonomers which were prepared via enzymatic polymerization that allows avoiding the usage of potentially toxic catalyst. To prepare hybrid NPs, TA was additionally added to the organic phase.
View Article and Find Full Text PDFHybrid polymers containing pyrene (Py) units bound to linear poly(silsesquioxane) (LPSQ) chains through flexible linkers containing heteroatoms (S, N, O) (LPSQ-triazole-Py and LPSQ-amide-Py) exhibit intense fluorescence emission, both in very diluted solutions (c = 10-8 mol/L) and in the solid state. The materials are thermally stable and exhibit good thin film forming abilities. Their optical and physicochemical properties were found to be strongly dependent on the structure of the side chains.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
June 2020
Microbial infections lead to elevated inflammatory responses, which usually result in prolonged and incomplete wound healing. Therefore, there is an increasing demand for biodegradable fibres that are effective against a different range of microorganisms, especially those with antibiotic resistance. Herein, quercetin-(Q)-loaded polylactide-based fibres were developed using the electrospinning technique.
View Article and Find Full Text PDFThis paper presents the effect of end groups, chain structure, and stereocomplexation on the microparticle and nanoparticle morphology and thermal properties of the supramolecular triblock copolyesters. Therefore, the series of the triblock copolymers composed of l,l- and d,d-lactide, trimethylene carbonate (TMC), and ε-caprolactone (CL) with isopropyl ( iPr) or 2-ureido-4-[1 H]-pyrimidinone (UPy) end groups at both chain ends were synthesized. In addition, these copolymers were intermoleculary stereocomplexed by polylactide (PLA) blocks with an opposite configuration of repeating units to promote their self-assembly in various organic solvents.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
December 2017
We investigated the distribution of polyglycidol and polystyrene on the surface of poly(styrene/α-tert-butoxy-ω-vinylbenzyl-polyglycidol) microspheres (random distribution or segregated into hydrophilic and hydrophobic patches), using fibrinogen (Fb) as a macromolecular probe. The fibrinogen was adsorbed or covalently attached to the surface of the poly(styrene-co-α-tert-butoxy-ω-vinylbenzyl-polyglycidol) (P(S/PGLy)) microspheres. The P(S/PGLy) particles were prepared by emulsion copolymerization of styrene and α-tert-butoxy-ω-vinylbenzyl-polyglycidol (PGLy) macromonomer initiated with potassium persulfate.
View Article and Find Full Text PDFLinear oligomeric silsesquioxanes with polar side moieties (e.g., carboxylic groups and derivatives of N-acetylcysteine, cysteine hydrochloride or glutathione) can form specific, self-assembled nanostructures when deposited on mica by dip coating.
View Article and Find Full Text PDFLinear oligomeric [2-(carboxymethylthio)ethylsilsesquioxanes] (LPSQ-COOH) adsorb spontaneously on muscovite mica and form smooth, well-ordered lamellar structures at the liquid-solid interface. Side carboxylic groups, having donor-acceptor character with regard to hydrogen bonds, are engaged both in multipoint molecule-to-substrate interactions and intermolecular cross-linking. The unique arrangement of silsesquioxane macromolecules, with COOH groups situated at the interface with air, produces highly hydrophilic surfaces of good thermal and solvolytic stability.
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