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Introduction. N. N. Blokhin National Medical Research Center of Oncology of the Ministry of Health of Russia synthesized an original derivative of indolocarbazole with the carbohydrate residue xylose, which has a pronounced cytotoxic and anti-angiogenic activity. The substance LCS-1269 is an amorphous powder that is almost insoluble in water, which causes difficulties in the development of an injectable dosage form (IDP). To solve this problem, a technological approach to obtain a solid dispersion (SD) of LCS-1269 has been proposed.Aim. To develop a model of IDP of the indolocarbazole derivative LCS-1269 based on SD.Materials and methods. We used a substance LCS-1269 synthesized in the Chemical Synthesis Laboratory of the N. N. Blokhin National Medical Research Center of Oncology. Emuxol 268, Kolliphor® P 188, Soluplus®, Lutrol® F68, Kollidon® 12 and Kollidon® 17, soybean phosphatidylcholine unsaturated S PC and saturated S PC-3 were investigated as carriers of the active substance. SD LCS-1269 was obtained by solvent removal: the active substance was dissolved in acetone, the carrier − in chloroform, the obtained solutions were mixed, transferred into a bottle and evaporated under vacuum (50 ± 5 mbar) in the desiccator at water bath temperature 65 ± 2 °С. To obtain aqueous solution of LCS-1269 dry mass was dissolved using different auxiliary substances or their mixtures: water for injection, ethanol 95 %, benzyl alcohol, Kollisolv® PEG 400, MONTANOX™ 80. To increase stability, the aqueous solution of LCS-1269 was lyophilized in an Edwards Minifast DO.2 freeze dryer.Results and discussion. Kollidon® 17 was chosen as the carrier material for the SD active substance. It was found that a clear solution of LCS-1269 with the concentration of the active substance 0.5 % was formed by dissolving the SD in ethanol 95 % and then gradually diluting the alcohol mixture with water for injection. In this case, the mass ratio of the components of the developed model IDF LCS : Kollidon® 17 : ethanol : water is 1 : 40 : 32 : 127. As a result of freeze-drying of the water-ethanol solution of LCS-1269 the IDF in the form of lyophilizate easily soluble in a 10 % solution of ethanol was obtained.Conclusion. An IDF model of the hydrophobic derivative of indolocarbazole LCS-1269 based on SD was developed and submitted for biological studies to evaluate its effectiveness.

The objective of the present study was to improve the dissolution rate and aphrodisiac activity of tadalafil by using hydrophilic polymers. Solid dispersions were prepared by solvent evaporation-Rota evaporator using Koliphore 188, KollidonR VA64, and KollidonR 30 polymers in a 1:1 ratio. Prepared tadalafil-solid dispersions (SDs) evaluated for yield, drug content, micromeritics properties, physicochemical characterizations, and aphrodisiac activity assessment. The optimized SDs TK188 showed size (2.175 ± 0.24 mm), percentage of content (98.89 ± 1.23%), yield (87.27 ± 3.13%), bulk density (0.496 ± 0.005 g/cm3), true density (0.646 ± 0.003 g/cm3), Carr's index (23.25 ± 0.81), Hausner ratio (1.303 ± 0.003) and angle of repose (<25°). FTIR spectrums revealed tadalafil doesn't chemically interact with used polymers. XRD and DSC analysis represents TK188 SDs were in the amorphous state. Drug release was 97.17 ± 2.43% for TK188, whereas it was 32.76 ± 2.65% for pure drug at the end of 2 h with 2.96-fold increase in dissolution and followed release kinetics of Korsmeyer Peppa's model. MDT and DE were noted to be 17.48 minutes and 84.53%, respectively. Furthermore, TK188 SDs showed relative improvement in the sexual behavior of the male rats. Thus the developed SDs TK188 could be potential tadalafil carriers for the treatment of erectile dysfunction. [ABSTRACT FROM AUTHOR]

The objective of the present study was to improve the dissolution rate and aphrodisiac activity of tadalafil by using hydrophilic polymers. Solid dispersions were prepared by solvent evaporation-Rota evaporator using Koliphore 188, Kollidon® VA64, and Kollidon® 30 polymers in a 1:1 ratio. Prepared tadalafil-solid dispersions (SDs) evaluated for yield, drug content, micromeritics properties, physicochemical characterizations, and aphrodisiac activity assessment. The optimized SDs TK188 showed size (2.175 ± 0.24 µm), percentage of content (98.89 ± 1.23%), yield (87.27 ± 3.13%), bulk density (0.496 ± 0.005 g/cm3), true density (0.646 ± 0.003 g/cm3), Carr’s index (23.25 ± 0.81), Hausner ratio (1.303 ± 0.003) and angle of repose (

In the past decade, various interfacial materials have been explored for better sensor performance in nanoplasmonics. Despite gold being an ideal candidate for many plasmonic applications, its use in the field of surface plasmon-coupled emission (SPCE) platform is limited due to its inherent quenching phenomenon. Different methodologies have been reported to circumvent this limitation, albeit compromised by complex requirements. Moreover, the SPCE enhancement obtained hitherto remains inadequate and the use of biocompatible and eco-friendly sustainable methods in this direction has been rare. In this perspective, here we demonstrate a frugal and bio-friendly technique using ubiquitously available co-polymer kollidon® to obtain silver (Ag)-gold (Au) nanohybrids. The methodology involved is a simple, user-friendly and economical UV-induced one-pot green synthesis of hybrid architectures. The nanoparticles and nanohybrids obtained through this method were studied in three different nanointerfaces, namely: spacer, cavity and extended (ext.) cavity. Dequenched as well as in excess of 1000-fold enhancement in fluorescence was obtained in the ext. cavity nanointerface on account of hybrid plasmonic resonances. In addition to this, attomolar sensitivity was achieved for biologically important amino acid, tyrosine using a mobile phone-based detection technique. The methodology reported in this work provides a straightforward technique to obtain nanohybrids that can be used to dequench the otherwise quenched emission with new physicochemical insights, in addition to providing ample opportunities for development of next-gen mobile phone based hazardous analyte detection platforms using sustainable methodologies. AgAu Nanohybrids for Attomolar Tyrosine Sensing in Smartphone-based Extended Cavity Plasmon-Coupled Dequenched Nanointerface. [Display omitted] • Sustainable bio-polymer kollidon® mediated silver-gold rapid nanohybrid synthesis. • Simple, user-friendly and economical renewable UV-light induced one-pot approach. • 1000-fold fluorescence enhancement at functional plasmon-coupled nanointerface. • Attomolar sensitivity for tyrosine using smartphone-based detection technology. [ABSTRACT FROM AUTHOR]

The goal was to use temporal gastrointestinal transit simulations and formulation to predict and provide sustained input of target-site directed oral drug delivery exclusively into the colon. Using mesalamine as the model drug for formulation coupled with stomach emptying rates (fed and unfed) plus intestinal transit times demonstrates concepts and provides a specific example for treatment in ulcerative colitis. Formulation involved extrusion and spheronization into beads which were then coated with aqueous Eudragit® S. Drug is released only at colonic pH and gastrointestinal transit predicts sustained drug input into the colon, especially when food effects are included. [ABSTRACT FROM AUTHOR]