Effect of synthesis conditions on the properties of magnetic nanoflowers

Magnetic nanoflowers (MNF) can be applied in complementary cancer therapy treatment, however, some of the preparation conditions and stability experiments have not been examined in great detail. In this study, magnetite nanoparticles (NPs) with flower-like architecture were synthesized, characterized and tested by magnetic hyperthermia. The preparation and characterization of flower-shaped magnetic objects were optimized in two types of reaction vessels. The two different synthesis methods resulted in magnetic nanoparticles (MNP) of slightly different morphology, resulting in different behavior for hyperthermia. The stability of the NPs was achieved by the application polymer functionalization both by in situ and postcoating methods

Serum Albumin Nanoparticles: Problems and Prospects

The present paper aims to summarize the results regarding serum albumin-based nanoparticles (NPs) for drug delivery purposes. In particular, it focuses on the relationship between their preparation techniques and synthesis parameters, as well as their successful clinical application. In spite of the huge amount of consumed material and immaterial sources and promising possibilities, products made from different types of albumin NPs, with the exception of a few, still have not been invented. In the present paper, promising applications of serum albumin nanoparticles (SANPs) for different biomedical purposes, such as carriers, delivery systems and contrast agents, are also discussed. The most frequent utilization of the NPs for certain diseases, i.e., cancer therapy, and future prospects are also detailed in this study

Vitamin E-Loaded PLA- and PLGA-Based Core-Shell Nanoparticles: Synthesis, Structure Optimization and Controlled Drug Release

The (±)-α-Tocopherol (TP) with vitamin E activity has been encapsulated into biocompatible poly(lactic acid) (PLA) and poly(lactide-co-glycolide) (PLGA) carriers, which results in the formation of well-defined nanosized (d ~200–220 nm) core-shell structured particles (NPs) with 15–19% of drug loading (DL%). The optimal ratios of the polymer carriers, the TP active drug as well as the applied Pluronic F127 (PLUR) non-ionic stabilizing surfactant, have been determined to obtain NPs with a TP core and a polymer shell with high encapsulation efficiency (EE%) (69%). The size and the structure of the prepared core-shell NPs as well as the interaction of the carriers and the PLUR with the TP molecules have been determined by transmission electron microscopy (TEM), dynamic light scattering (DLS), infrared spectroscopy (FT-IR) and turbidity studies, respectively. Moreover, the dissolution of the TP from the polymer NPs has been investigated by spectrophotometric measurements. It was clearly confirmed that increase in the EE% from ca. 70% (PLA/TP) to ca. 88% (PLGA65/TP) results in the controlled release of the hydrophobic TP molecules (7 h, PLA/TP: 34%; PLGA75/TP: 25%; PLGA65/TP: 18%). By replacing the PLA carrier to PLGA, ca. 15% more active substance can be encapsulated in the core (PLA/TP: 65%; PLGA65/TP: 80%)

Önszerveződő hibrid filmek előállítása nanoszerkezetű anyagokból = Preparation of self-assembled hybrid films from nanostructured materials

Önszerveződő hibrid nanofilmek előállítását, szerkezeti és optikai tulajdonságait vizsgáltuk különböző kolloidokból felépíthető ultravékony rétegekben. Funkcionált felületű nanorészecskékből szabályozott szerkezetű nanohibrid ultravékony filmeket készítettünk. A félvezető-oxidok közül a cink-oxid részecskéket alkalmaztuk önszerveződő filmek építéséhez és szenzorok előállításához. Réteges szerkezetű nanolamellás rendszerek kiváló önszerveződő tulajdonságokkal rendelkeznek a lamellák anizometrikus dimenziói miatt. A hibrid rétegek további komponensei lehetnek polimerek, peptidek és fehérjék is. Az önrendeződés folyamatát kétdimenziós kísérletekben Langmuir-mérleggel is követtük és jellemeztük a filmek kompresszibilitását. Az ezüst plazmonikus tulajdonságait kihasználva a látható fényben gerjeszthető fotokatalizátorokat készítettünk és azok hatékonyságát fotooxidációs reakciókkal minősítettük. Kvázi-kétdimenziós optikai reflexiós spektroszkópiával tanulmányoztuk a hidrofil és hidrofób nanohibrid filmeket. Funkcionalizált arany részecskékkel gőzök adszorpciójára szenzitív interdigitális szenzorokat fejlesztettünk ki. Aminosavak funkcionalizáló hatását tanulmányoztuk, és a plazmonikus anyagok felületén bekövetkező szorpciós folyamatok alkalmasak az ezüst valamint az arany nanorészecskék felületén megkötött biokolloidok tulajdonságainak optikai jelzésére. Ez a módszer kifejleszthető gyógyszer hatóanyagok megkötésének kvantitatív detektálására protein szupramolekulákra. | Structural and optical properties of self-assembled hybrid nanofilms prepared from different colloids were investigated. The nanohybrid ultrathin films with tailored structure were prepared from functionalized nanoparticles. Semiconductor metal oxide (zinc oxide) nanoparticles were applied for the construction of self assembled films for sensor application. The layered structured nanolamellar systems exhibit excellent self assembled properties because of the anisometric dimensions of the lamellae. Further components of the hybrid layers may also involve polymers, peptides and proteins as well. The self-assembly process was controlled by two dimensional Langmuir-balance measuring the compressibility of the films. The plasmonic properties of silver were exploited for photocatalysis. The catalysts can be excited in visible light and their efficiency in photooxidation reactions was determined. Quasi-two dimensional optical reflection spectroscopy on hydrophilic and hydrophobic nanohybrid films were studied using setup developed in our laboratory. Gold nanoparticles were deposited on interdigital sensor surfaces measuring the vapours adsorption. The effect of surface functionalization by amino acids were also studied. The sorption processes are able to modify the optical signal on the surface of plasmonic materials for biocolloids on plasmonic surfaces. This method can be developed for quantitative characterization of pharmaceutical drug materials binding on supramolecules

The provenance of the raw material and the manufacturing technology of copper artefacts from the Copper Age hoard from Magyaregres, Hungary.

In 2016, a Stollhof-type copper hoard was found during an excavation in Magyaregres, Hungary. It was placed in a cooking pot, and deposited upside down within the boundaries of an Early Copper Age settlement. Similar hoards dating to the end of the 5th millennium BCE are well-known from Central Europe, however, this hoard represents the only one so far with thoroughly documented finding circumstances. The hoard contained 681 pieces of copper, 264 pieces of stone and a single Spondylus bead, along with 19 pieces of small tubular spiral copper coils, three spiral copper bracelets, and two large, spectacle spiral copper pendants. Until now, information on the provenance of raw materials and how such copper artefacts were manufactured has not been available. The artefacts were studied under optical microscopes to reveal the manufacturing process. Trace elemental composition (HR-ICP-MS) and lead isotope ratios (MC-ICP-MS) were measured to explore the provenance of raw materials. The ornaments were rolled or folded and coiled from thin sheets of copper using fahlore copper probably originating from the Northwestern Carpathians. A complex archaeological approach was employed to reveal the provenance, distribution and the social roles the ornaments could have played in the life of a Copper Age community. Evidence for local metallurgy was lacking in contemporaneous Transdanubian sites, therefore it is likely that the items of the hoard were manufactured closer to the raw material source, prior to being transported to Transdanubia as finished products. The method of deposition implies that such items were associated with special social contexts, represented exceptional values, and the context of deposition was also highly prescribed. The Magyaregres hoard serves as the first firm piece of evidence for the existence of a typologically independent Central European metallurgical circle which exploited the raw material sources located within its distribution

Rational Mitomycin Nanocarriers Based on Hydrophobically Functionalized Polyelectrolytes and Poly(lactide-co-glycolide)

[Image: see text] Encapsulation of hydrophilic and amphiphilic drugs in appropriate colloidal carrier systems for sustained release is an emerging problem. In general, hydrophobic bioactive substances tend to accumulate in water-immiscible polymeric domains, and the release process is controlled by their low aqueous solubility and limited diffusion from the nanocarrier matrix. Conversely, hydrophilic/amphiphilic drugs are typically water-soluble and insoluble in numerous polymers. Therefore, a core–shell approach—nanocarriers comprising an internal core and external shell microenvironments of different properties—can be exploited for hydrophilic/amphiphilic drugs. To produce colloidally stable poly(lactic-co-glycolic) (PLGA) nanoparticles for mitomycin C (MMC) delivery and controlled release, a unique class of amphiphilic polymers—hydrophobically functionalized polyelectrolytes—were utilized as shell-forming materials, comprising both stabilization via electrostatic repulsive forces and anchoring to the core via hydrophobic interactions. Undoubtedly, the use of these polymeric building blocks for the core–shell approach contributes to the enhancement of the payload chemical stability and sustained release profiles. The studied nanoparticles were prepared via nanoprecipitation of the PLGA polymer and were dissolved in acetone as a good solvent and in an aqueous solution containing hydrophobically functionalized poly(4-styrenesulfonic-co-maleic acid) and poly(acrylic acid) of differing hydrophilic–lipophilic balance values. The type of the hydrophobically functionalized polyelectrolyte (HF-PE) was crucial for the chemical stability of the payload—derivatives of poly(acrylic acid) were found to cause very rapid degradation (hydrolysis) of MMC, in contrast to poly(4-styrenesulfonic-co-maleic acid). The present contribution allowed us to gain crucial information about novel colloidal nanocarrier systems for MMC delivery, especially in the fields of optimal HF-PE concentrations, appropriate core and shell building materials, and the colloidal and chemical stability of the system