Poor aqueous solubility is often linked with a poor dissolution rate and ultimately, limited bioavailability of pharmaceutical compounds. This study describes the application of mesoporous materials (Syloid 244 and Syloid AL1) in improving the dissolution rate of a drug with poor aqueous solubility, namely artemether, utilising different processing methods including physical mixing, co-grinding and solid dispersions prepared by solvent evaporation and the lyophilisation technique. The prepared formulations were extensively characterised for their solid-state properties and the drug release attributes were studied. Differential scanning calorimetry and X-ray diffraction confirmed conversion of crystalline artemether into a disordered and amorphous form, whilst no intermolecular interactions were detected between artemether and silica. Both silica grades enhanced the dissolution rate of artemether in comparison with drug alone, for example from 17.43% (±0.87%) to 71.55% (±3.57%) after 120mins with lyophilisation and Syloid 244 at a 1:3 ratio. This enhancement was also dependant on the choice of processing method, for example, co-ground and lyophilised formulations prepared with Syloid 244 at 1:3 ratio produced the most extensive dissolution, thus endorsing the importance of materials as well as choice of formulation method.

Yttrium oxide (Y2O3) is a promising rare-earth compound that is rarely studied. This study reports on the synthesis, structural, morphological, optical and antimicrobial properties of Y2O3 nanoparticles (NPs) synthesized using Agathosma betulina leaf extract. XRD pattern indicated that the crystalline phase was achieved for the sample calcined at [Formula: see text]C with body-centered cubic symmetry. SEM and TEM images of Y2O3 nanopowder showed the nearly spherical morphology of agglomerated NPs with an average diameter of 13[Formula: see text]nm. Optical properties revealed that the bandgap of Y2O3 NPs ([Formula: see text][Formula: see text]eV) has been increased compared with the bulk Y2O3 ([Formula: see text][Formula: see text]eV). Moreover, the antimicrobial activity was also evaluated against gram-positive and gram-negative bacteria of clinical interest. Results demonstrated that the synthesized Y2O3 NPs exhibited higher bacteriostatic effects against gram-negative bacterial strains due to their thin cell wall structure. These results show that the synthesized Y2O3 NPs are suitable for antibacterial control systems and medicines.

This paper describes graduate chemistry practical related to mutual solubility of liquids and phase coexistence. The diversity of the phase transition shows that heating produces mixing and separation. The practical consists of short experiment on the general theme of miscibility of aqueous and organic phases by varying the temperature. The phases were selected as phenol -water and nicotine-water system. The experiment was preceded by the interaction of equal quantities of phenol-water and nicotine-water at room temperature and higher temperature about 80°C. There was a change in miscibility of phases at higher temperature. At about 80°C the phenolwater mixture becomes monophasic while it is heterogeneous at room temperature. The waterphenol phase show limited miscibility below 70 °C. While the nicotine -water phases become heterogenous at higher temperature and at room temperature they were monophasic. The temperature at which these phases were merges is known as clearing temperature or cloud temperature. It lies on the liquid-liquid coexistence line. The experiment required careful observations by students at various temperatures ranges from 20 o C to 100 o C at the step of 20 0 C and followed by result and discussions. Analysis of the data predicted that students were enjoying by working out the practical and it would be bestowing tremendously beneficial learning experience. The aim of this study was to explore the concept of the phenomenon of phase changes by varying the temperatures and can interpret macroscopic and microscopic properties of the system by relating to the thermodynamic properties. These experiments were beneficial for the isolation and separation of toxic compounds like nicotine and phenol from the waste stream. It is effective and low cost method to save the environment and ecosystem.