In the present work, activated-carbon-containing pellets were preparedby direct chemical activation of sawdust, using clays as a binder. The obtained pellets (ACC) were coated with hydroxyapatite (HAp) nanoparticles (ACC-HAp) to improve adsorption towards Pb(II), Cu(II), Zn(II), and Ni(II). The pellets were characterized by scanning electron microscopy (SEM), by Fourier transform infrared spectroscopy (FTIR), and with a gas sorptometer. The effect of pH, contact time, and initial concentration on adsorption performance was investigated. Additionally, desorption studies were performed, and the regeneration influence on compressive strength and repeated Pb(II) adsorption was investigated. The results showed that, after coating ACC pellets with HAp nanoparticles, the adsorption capacity increased for all applied heavy metal ions. Pb(II) was adsorbed the most, and the best results were achieved at pH 6. The adsorption process followed the pseudo-second-order kinetic model. The adsorption isotherm of Pb(II) is better fitted to the Langmuir model, showing the maximum adsorption capacity of 56 and 47 mg/g by ACC-HAp and ACC pellets, respectively. The desorption efficiency of Pb(II)-loaded ACC-HAp pellets increased by lowering the pH of the acid, resulting in the dissolution of the HAp coating. The best desorption results were achieved with HCl at pH 1 and 1.5. Therefore, the regeneration procedure consisted of desorption, rinsing with distilled water, and re-coating with HAp nanoparticles. After the regeneration process, the Pb(II) adsorption was not affected. However, the desorption stage within the regeneration process decreased the compressive strength of the pellets.
Shungite is a natural carbon containing material that is widely used in water treatment. Scientific research shows that shungite has good adsorption properties towards various organic compounds and heavy metals, as well as exhibiting antibacterial properties. Unfortunately, at the same time shungite releases various chemical elements into the water, including heavy metals. In this study changes in concentration of various heavy metals during drinking water treatment with one commercial and one non-commercial shungite sample were determined. Also sorption of Cu(II) with initial concentration of 2,500 μg/L onto shungite was investigated. The results showed that various heavy metals like nickel, copper, lead, cadmium, zinc, chromium and arsenic are leaching from shungite into water. Lead and cadmium exceeded the maximum acceptable concentration in drinking water for a few days, but nickel exceeded for up to 2 weeks. At the same time shungite showed good adsorption properties towards copper. Nevertheless, before using shungite in drinking water treatment, it would be advisable to assess the necessity and/or wash shungite with larger volumes of water for a longer period of time than is written in the instructions.
This review explores the molecular and cellular pathways of soft tissue wound healing and the potential therapeutic use of the non-psychotropic cannabinoid cannabidiol (CBD), integrating findings from in vitro and in vivo preclinical studies as well as completed and ongoing clinical trials. It provides a comprehensive summary of the next steps in new CBD-based product development by analyzing current trends in dosage optimization, treatment guidance, delivery systems, ranging from liposomes, microemulsions to hydrogels. Additionally, the review examines clinical trials related to CBD formulations, delivery routes, and participant outcomes, offering a deeper understanding of the mechanisms guiding the activity beyond binding to cannabinoid 1 (CB1) and CB2 receptors. Furthermore, it highlights challenges and future perspectives in CBD formulation studies, presenting both currently studied approaches and emerging possibilities for innovation. Therapeutic potential of CBD has proved itself in the recent years and only regulatory issues and clarity in treatment and delivery routes will limit its widespread use in soft tissue healing.
Calcium phosphate ceramics are one of the most studied biomaterials for bone substitution and regeneration. Bioactivity is one of the most important properties for these materials and it can be evaluated by adsorption of proteins and by hydroxyapatite formation on the surface in simulated body fluid (SBF). The aim of this work was to evaluate the bioactivity of ceramic granules with various hydroxyapatite (HAp) and beta tricalcium phosphate (β-TCP) ratios by adsorption of bovine serum albumin (BSA) in SBF and phosphate saline buffer (PBS) solution. The highest adsorption capacity in both solutions was observed for biphasic calcium phosphate sample with HAp/β-TCP ratio 50/50 but the lowest – for sample 10/90. The adsorption capacity of all samples was more than 2 times higher in SBF media than in PBS. The possibility of hydroxyapatite formation was evaluated by changes of Ca2+ concentration in SBF. After 5 days of incubation at 37oC all samples showed a decrease in Ca2+ concentration.