Synthesis, characterization and cyclic voltammetric study of copper(II) and nickel(II) polymer chelates

Microwave assisted synthesis of polyacrylamide grafted polymeric blend of fenugreek seed mucilage-Polyvinyl alcohol (FSM-PVA-g-PAM) and its characterizations as tissue engineered scaffold and as a drug delivery device

Microwave assisted synthesis of graft copolymer of polymeric blend of Fenugreek seed mucilage (FSM)-Polyvinyl alcohol (PVA) with acrylamide (AM) was done by free radical polymerization using ammonium per sulfate (APS) as initiator. Varying amount of AM and APS was used to optimize the best grade based on highest percentage grafting efficiency and investigated with intrinsic viscosity measurement, Fourier Transformation infrared spectroscopy (FTIR),13C NMR spectra, X-ray diffraction, elemental analysis, Thermogravimetric analysis, Scanning electron microscopy. The results of intrinsic viscosity indicate that the optimized sample GF4 has longer chain length than in comparison to the native mucilage and thus exhibits more swelling tendencies and thus can be used as very good controlled release matrix system. The thermal analysis and X-ray indicates that GF4 is more stable and possess more amorphous properties than the native FSM. The NMR and FT-IR studies reveal that in GF4 there is prominent presence of amide and the hydroxyl groups indicating that grafting mechanism has efficiently taken place. Histological studies & SEM image for optimized grade implanted on animals revealed sufficient tissue growth and exhibited biodegradability proving the material to be biocompatible and suitable to be used as tissue engineered scaffolds. The controlled release behavior of the optimized polymeric system GF4 was evidenced by 95% release of loaded drug Enalapril maleate for 16 h. Graphical abstract.

Long-term impact of heavy metals on the performance of biological wastewater treatment processes during shock-adaptation-restoration phases

The present work investigated the long-term (30 days of shock-adaptation and 60 days of restoration) impact of Cu²⁺, Hg²⁺ and Ag⁺ shock loading on the performance of biological wastewater treatment processes. Under the same inhibitory concentration (IC₁₅), Cu²⁺ had the most significant impact on the treatment efficiency. During the shock-adaptation phase, Ag⁺ led to up to 4 times of biopolymers generation compared to that of the blank one; Hg²⁺ inhibited the nitrification process but showed little influence on other parameters; Cu²⁺ and Ag⁺ inhibited the activity of sDHA completely and decreased the content of ATP significantly, as well they caused abnormal ROS generation and corresponding CAT and SOD increment. Till 60 days of restoration can the activity of enzymes be restored to the control level, which agreed well with the results of effluent quality. Cu²⁺ decreased the biodiversity of the sludge to a large extent, followed by Ag⁺ and Hg²⁺. At the phylum level, Verrucomicrobia was decreased nearly to zero after 30 days of Cu²⁺ shock. At the genera level, Zoogloea was almost vanished after 15 days of Cu²⁺ shock.