Pyrophyllite clay, modified with PVP coated silver nanoparticles (PYRO-PVP/AgNPs), with recently proved antibacterial activity was prepared. Silver nanoparticles were synthesized by the chemical reduction method of AgNO3 using NaBH4 and poly(vinyl pyrrolidone) (PVP) as a stabilizer and excellent dispersant. This research aimed to elucidate the mechanisms and kinetics of AgNPs, along with the PVP protective mechanism responsible for antibacterial activity towards the microorganisms. Pioneering steps were made toward coagulation studies due to the potential of aluminosilicate layered clays to serve as alternatives to hemostatic agents currently in use. The isoelectric point of pyrophyllite samples with 5, 20, and 45 μm diameter particles and PYRO/PVP/AgNPs sample (Ag25mg/L) was evaluated to understand how the anticoagulant or procoagulant properties of the pyrophyllite varied according to the pH of the isoelectric point. Characterization of the PYRO-PVP/AgNPs samples was performed using FTIR spectroscopy, while the release mechanism and kinetics of silver ions were monitored using atomic absorption spectroscopy (AAS). Additionally, AAS was used for the evaluation of heavy metals content in pyrophyllite clay and a simple, cost-effective procedure was proposed for the extraction of heavy metals.

Biodegradable polymers (biopolymers) represent materials of new generation with application in different areas of human activity. Their production has recently reached a commercial level. They can be divided according to the origin (natural and synthetic), according to the chemical composition, methods of obtaining, application etc. The use of biopolymers in medicine depends on their biocompatibility, mechanical resistance, and sorptive characteristics. Today, they are the most commonly used as implants in vascular and orthopedic surgery, for the production of materials such as catheters, products for gynaecology and haemodialysis, tooth reconstruction, etc. In pharmacy, they are used as a medicine matrix-carrier to allow controlled release of drug within the body. Within this review paper, the properties and methods of production of certain biopolymers such as polyglycolic acid (PGA), polylactide acid (PLA), poly-ε-coprolactone (PCL) and polybutylene succinate (PBS) will be described in detail, as well as their application in medicine and pharmacy.

The research includes analysis of: pH value, organic matter content, and the total concentration of manganese in eleven soil samples from different localities northeast of Bosnia and Herzegovina. Sequential extractions of soil samples were also performed to determine the content of some form of binding manganese. Concentration of manganese in the flowers of calendula were also found and tested at these sites. From the obtained measurement, BCF (Bioconcentration Factor) values were calculated for the tested metal. Soil pH had values from 7.84 to 8.54, which puts them in the category of alkaline and strongly alkaline soil. The total concentration of manganese measured in soil samples do not exceed the limit values or are above average values. In the analyzed soil samples, the minimum content of manganese in the exchangeable fraction and the largest in the residual fraction and bound for oxides of manganese and iron. The concentrations of manganese in the flowers of calendula have not exceeded the permitted value. Statistical analysis of the results showed a weak linear correlation between pH value of an aqueous solution of the soil and the content of manganese in the flower, and linear correlation between manganese in the exchangeable fraction and the content of manganese in the flower. The calculated BCF values are very low and suggest that calendula growing on alkaline soil hasn’t got an expressed potential for accumulation of manganese.