Luminescent silica mesoparticles for protein transduction

Unlike silica nanoparticles, the potential of silica mesoparticles (SMPs) (i.e. particles of submicron size) for biological applications in particular the in vitro (let alone in vivo) cellular delivery of biological cargo has so far not been sufficiently studied. Here we examine the potential of luminescent (namely, octahedral molybdenum cluster doped) SMPs synthesised by a simple one-pot reaction for the labelling of cells and for protein transduction into larynx carcinoma (Hep-2) cells using GFP as a model protein. Our data demonstrates that the SMPs internalise into the cells within half an hour. This results in cells that detectably luminesce via conventional methods. In addition, the particles are non-toxic both in darkness and upon photo-irradiation. The SMPs were modified to allow their functionalisation by a protein, which then delivered the protein (GFP) efficiently into the cells. Thus, the luminescent SMPs offer a cheap and trackable alternative to existing materials for cellular internalisation of proteins, such as the HIV TAT protein and commercial protein delivery agents (e.g. Pierce™)

From photoinduced to dark cytotoxicity via an octahedral cluster hydrolysis

Octahedral molybdenum and tungsten clusters have potential biological applications in photodynamic therapy and bioimaging. However, poor solubility and hydrolysis stability of these compounds hinder their application. The first water-soluble photoluminescent octahedral tungsten cluster [{W6I8}(DMSO)6](NO3)4 was synthesised and demonstrated to be at least one order of magnitude more stable towards hydrolysis than its molybdenum analogue. Biological studies of the compound on larynx carcinoma cells suggest that it has a significant photoinduced toxicity, while the dark toxicity increases with the increase of the degree of hydrolysis. The increase of the dark toxicity is associated with the in situ generation of nanoparticles that clog up the cisternae of rough endoplasmic reticulum

Properties of binary oxides:a DFT study

Abstract Titanium dioxide nanoparticles are used in an enormous amount of applications. Their properties are different from bulk TiO₂ and are affected by adsorbates that are unavoidably present on the surface. In this thesis, the effect of OH and SO₄ groups (the adsorbants present on the surface during manufacturing) on the properties of anatase-structured TiO₂ nanoparticles is studied. It was found that the above mentioned groups change both the geometric and electronic structure of nanoparticles, resulting in changes in the photoabsorption spectrum. Bader charges are calculated using electron density from Density Functional Theory calculations. They can be used for determination of the oxidation state of the atom. The relation between computed partial charges and oxidation states for binary oxides using data from open materials database has been demonstrated in this work using a linear regression. The applicability of the oxidation state determination by Bader charges for mixed valence compounds and surfaces is considered.Tiivistelmä Titaanidioksidinanopartikkeleita käytetään lukuisissa sovelluksissa. Niiden ominaisuudet poikkeavat kiinteän TiO₂:n ominaisuuksista, ja niihin vaikuttavat pinnalle väistämättä absorboituvat aineet. Tässä työssä on tutkittu OH- ja SO₄-ryhmien vaikutusta anataasirakenteisten TiO₂-nanopartikkelien ominaisuuksiin. Tällaisia ryhmiä esiintyy yleisesti nanopartikkelien pinnalla valmistusprosessien aikana. Työssä havaittiin, että nämä ryhmät muuttavat nanopartikkelien rakenteellisia ja sähköisiä ominaisuuksia, ja siten vaikuttavat myös fotoabsorptiospektriin. Baderin varaukset voidaan laskea käyttäen tiheysfunktionaaliteoriaan perustuvista laskuista saatavaa elektronitiheyttä. Niitä voidaan käyttää atomin hapetustilan laskemiseen. Tässä työssä on osoitettu, että binääristen oksidien tapauksessa laskettujen osittaisvarauksien ja hapetustilan välillä on yhteys. Tämä yhteys voitiin osoittaa käyttämällä lineaarista regressiota. Työssä tarkastellaan myös menetelmän soveltuvuutta hapetustilojen määrittämiseen sekavalenssiyhdisteille ja pinnoille

A DFT study of the effect of SO₄ groups on the properties of TiO₂ nanoparticles

Abstract We present a study of the optical, electronic, and structural properties of TiO₂ anatase-structured nanoparticles upon adsorption of SO₄ groups, which are always present on the surface of the particles during the sulfate manufacturing method. Structural and electronic properties were studied using the density functional theory method (DFT), and optical properties were obtained by time-dependent DFT. It was found that SO₄ groups alter both the geometric and electronic structure of TiO₂ nanoparticles and change the photoabsorption characteristics. In particular, we find that ɳ²-O₂ type O–O moieties are formed due to the adsorption of 3 and 4SO₄ groups

Legal Consciousness and Legal Culture in the Era of Total Digitalization: Theoretical-methodological and Legal-technical Problems

The paper analyses the change in ideas about law in the digitalization era. Noting the insufficient theoretical substantiation of attempts to impose on modern law any special characteristics arising from the widespread development of digital technologies, the authors admit that in the era of virtual reality, the laws of the digital virtual world begin to actively compete with the laws of nature. This entails a slight decrease in the role of law as a traditional regulator of social relationships. However, according to the authors, one should not artificially diminish the role of law even in the era of digitalization. In this regard, the paper discusses the main trends in the study of legal digitalization processes. The first trend is due to the need to promptly respond by legal means to the emergence of new areas of legal regulation caused by the widespread use of digital information technologies. The second trend assumes the expansion and rethinking of the subject and object of legal science within the context that new digital "participants" of legal relations born due to intelligent human activity emerge.&nbsp