Polyelectrolyte micro- and nanoparticles with doxorubicin

Abstract

Doxorubicin containing micro and nanoparticles obtained by layer by layer adsorption of dex tran sulfate and chitosan on an insoluble antibiotic-polyanion complex with subsequent sonication were studied. The effects of the molecular mass of biopolymers, the number of polyelectrolyte layers, and the pH of the reaction medium on the composition, physicochemical properties, and the efficiency of doxorubicin incorporation have been examined. The release of doxorubicin and the mucoadhesive properties of the poly electrolyte particles have been analyzed to determine the possibilities of their potential applications.

Engineering method for predicting the displacement of the earth’s surface under the influence of stope workings of coal mines

“…For this reason, a practical coincidence of the results of determination with (table 3 and table 4) was obtained. Values close to them were also obtained using the results of correlation analysis (figure 4a), as evidenced by the close location of the bisector of the coordinate grid (1) and the averaging line (2).…”

“…Similar results were obtained when determining the values of the coordinates of characteristic points along the abscissa axis (figure 4b). The values L 1k ox are near the bisector of the coordinate grid (1), as is the averaging straight line (2).…”

“…It was also established that when the stope advance rate is less than 50 m/month, the value of the empirical coefficient b a p is approximately equal to 1330. Similarly, according to equations (2,3,4), the empirical coefficients a a p , b a p , c a p were calculated for the operating conditions of longwall No. 530 C ' 6 of the Yubileynaya mine seam (table 1).…”

“…In the first case, the coefficients of equation ( 1) are determined from the experimental data [17] and [8] by the least squares method (a k p , b k p , c k p ). In the second, using the operating conditions of the excavation sites (m, H, v ox ), according to equations (2,3,4), the empirical coefficients (a a p , b a p , c a p ) equations 1, respectively) were calculated.…”

“…Conducting cleaning operations in coal mines, even at depths of more than 1000 m, has an impact on changes in the state of the earth's surface. Initially, the study of the processes of formation of shear troughs on the earth's surface was aimed at solving one problem -of protecting buildings, structures and other objects from destruction and the harmful effects of mine workings [1][2][3][4]. Based on the results of these studies, a regulatory document [5] was developed, which regulated the rules for protecting structures and natural objects from the harmful effects of underground mine workings.…”