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Regarding the current state of the art on the utilization of zeolites in industry, the application of zeolites as an additive to eco-friendly energetic materials indicates the innovative character of the present research. One of the most commonly used energetic materials in the mining industry (engineering works) is ANFO (ammonium nitrate fuel oil), due to its easy and cheap production procedure as well as its good energetic properties and vast possibilities for modification. In the present research, we investigated Cu-zeolite with a faujasite structure (Cu-FAU) as a modifier of ANFO-based energetic materials. Analysis of the results obtained from thermodynamic calculations of energetic performance led to the conclusion that the application of Cu-faujasite as an additive to ANFO resulted in a relevant reduction in the total emission of post-decomposition fumes, with simultaneous enhancement of the energetic properties of the energetic material, which corresponded with the changes in the status of the surface and the reduced thermal effect accompanying the ammonium nitrate’s decomposition. From analysis of both the energetic performance and fumes, it may be concluded that our eco-friendly and enhanced energetic material can be used as a low-emission source of energy for the quarrying of raw materials. [ABSTRACT FROM AUTHOR]

In this research, we developed boron-rich nanoparticles that can be used for boron neutron capture therapy as potential carriers for boron delivery to cancerous tissues. Functionalized carbonated boron nitride nanostructures (CBNs) were successfully synthesized in self-propagating combustion waves in mixtures of high-nitrogen explosives and boron compounds. The products' composition, morphology, and structural features were investigated using Fourier transform infrared spectroscopy, powder X-ray diffraction, low-temperature nitrogen sorption analysis, thermogravimetric analysis, high-resolution scanning electron microscopy, and high-resolution transmission electron microscopy. The extreme conditions prevailing in combustion waves favor the formation of nanosized CBN hollow grains with highly disordered structures that are properly functionalized on the surface and inside the particles. Therefore, they are characterized by high porosity and good dispersibility in water, which are necessary for medical applications. During biological tests, a concentration-dependent effect of the obtained boron nitride preparations on the viability of normal and neoplastic cells was demonstrated. Moreover, the assessment of the degree of binding of fluorescently labeled nanoparticles to selected cells confirmed the relationships between the cell types and the concentration of the preparation at different incubation time points. [ABSTRACT FROM AUTHOR]

Physicochemical properties of immunolatex, prepared by incubation of negatively charged polystyrene microparticles with polyclonal rabbit IgGs, were determined by a variety of experimental techniques. These comprised dynamic light scattering (DLS), laser Doppler velocimetry (LDV) and atomic force microscopy (AFM). The particle diffusion coefficient, the hydrodynamic diameter, the electrophoretic mobility, the zeta potential and the suspension stability were determined as a function of pH for different ionic strengths. The deposition of the immunolatex on bare and polyallylamine (PAH) functionalized mica was investigated using the microfluidic oblique impinging-jet cell, with an in situ, real-time image analysis module. The particle deposition kinetics was acquired by a direct particle enumeration procedure. The measurements enabled us to determine the range of pH where the specific deposition of the immunolatex on these substrates was absent. We argue that the obtained results have practical significance for conducting efficient flow immunoassays governed by specific antigen/antibody interactions. [ABSTRACT FROM AUTHOR]

Fibrinogen (Fb) adsorption on positivelycharged latex particles(average diameter of 800 nm) was studied using the microelectrophoreticand the concentration depletion methods based on AFM imaging. Monolayerson latex were adsorbed from diluted bulk solutions at pH 7.4 and anionic strength in the range of 10–3to 0.15 M wherefibrinogen molecules exhibited an average negative charge. The electrophoreticmobility of the latex after controlled fibrinogen adsorption was systematicallymeasured. A monotonic decrease in the electrophoretic mobility offibrinogen-covered latex was observed for all ionic strengths. Theresults of these experiments were interpreted according to the three-dimensionalelectrokinetic model. It was also determined using the concentrationdepletion method that fibrinogen adsorption was irreversible and themaximum coverage was equal to 0.6 mg m–2for ionicstrength 10–3M and 1.3 mg m–2for ionic strength 0.15 M. The increase of the maximum coveragewas confirmed by theoretical modeling based on the random sequentialadsorption approach. Paradoxically, the maximum coverage of fibrinogenon positively charged latex particles was more than two times lowerthan the maximum coverage obtained for negative latex particles (3.2mg m–2) at pH 7.4 and ionic strength of 0.15 M.This was interpreted as a result of the side-on adsorption of fibrinogenmolecules with their negatively charged core attached to the positivelycharged latex surface. The stability and acid base properties of fibrinogenmonolayers on latex were also determined in pH cycling experimentswhere it was observed that there were no irreversible conformationalchanges in the fibrinogen monolayers. Additionally, the zeta potentialof monolayers was more positive than the zeta potential of fibrinogenin the bulk, which proves a heterogeneous charge distribution. Theseexperimental data reveal a new, side-on adsorption mechanism of fibrinogenon positively charged surfaces and confirmed the decisive role ofelectrostatic interactions in this process. [ABSTRACT FROM AUTHOR]

The aim of this work was to critically review recent results pertinent to fibrinogen adsorption at solid/electrolyte interfaces with the emphasis focused on a quantitative analysis of these processes in terms of the electrostatic interactions. Accordingly, in the first part, the primary chemical structure of fibrinogen is analyzed. Physicochemical data pertinent to the bulk properties derived from hydrodynamic, dynamic light scattering and micro-electrophoretic measurements aided by theoretical modeling are discussed. Possible conformations and the effective charge distribution over the fibrinogen molecule for various pH an ionic strength are defined, especially the semi-collapsed conformation prevailing at physiological conditions. Adsorption kinetics of fibrinogen at hydrophilic and hydrophobic (polymer modified) substrates determined by various techniques is described. Adsorption at polymeric carrier particles, pertinent to immunological assays, studied in terms of electrokinetic and concentration depletion methods, are also considered. The reversibility of adsorption, fibrinogen molecule orientations and maximum coverages are thoroughly discussed. The stability of fibrinogen monolayers formed at these carrier particles in respect to pH and ionic strength cyclic changes is also discussed. In the final section interactions and deposition of model colloid particles on fibrinogen monolayers are analyzed which allows one to derive valuable information about molecule orientations. Based on the physicochemical data, adsorption kinetics and colloid particle deposition measurements, probable adsorption mechanisms of fibrinogen on solid/electrolyte interfaces are defined.