Silylation of leached-vermiculites following reaction with imidazole and copper sorption behavior

Clays as Vehicles for Drug Photostability

Clay minerals are often used due to their high adsorption capacity, which has sparked interest in their biological applications to stabilize drugs and pharmaceutical products. This research aims to summarize information about the stability of drugs, cosmetics, dermocosmetics, and pharmaceutical compounds incorporated in the structure of different clay minerals. The databases used to search the articles were Web of Science, Scopus, PubMed, and Science Direct. Photostabilization of these compounds is reviewed and its importance demonstrated. For biological applications, the increase in solubility and bioavailability of clay minerals has proven useful for them as drug carriers. While their natural abundance, low toxicity, and accessible cost have contributed to classical applications of clay minerals, a wide range of interesting new applications may be facilitated, mainly through incorporating different organic molecules. The search for new functional materials is promising to challenge research on clay minerals in biological or biotechnological approaches.

Pentachlorophenol removal from aqueous solutions using Montmorillonite modified by Silane & Imidazole: kinetic and isotherm study

BACKGROUND

Removal of pentachlorophenol (PCP) from wastewater containing chlorophenols, due to its toxicity, mutagenic and carcinogenic properties, has been attracted much interests of researchers.

METHODS

In this research, K10 montmorillonite was modified by silane and imidazole (Im) for increasing the removal percentage of PCP from aqueous solutions. It was characterized by FTIR, XRF, FESEM, EDS, and BET techniques. The influence of different parameters such as initial concentration, contact time, adsorbent dosage, pH, temperature and agitating speed was investigated.

RESULTS

The maximum removal percentage (95%) were obtained for PCP at pH = 4. The isotherm experimental data for pentachlorophenol was best fitted using the Langmuir model and the kinetic studies were better described by the pseudo-second-order kinetic model. The thermodynamic study indicated that the adsorption of PCP by the adsorbent was feasible, spontaneous and exothermic.

CONCLUSION

In this study, the modified montmorillonite by silane and imidazole is appropriate and low cost adsorbent for increasing of the removal percentage of PCP from aqueous solutions.

Biomimetic strategies to design metallic proteins for detoxification of hazardous heavy metal

Discharge of hazardous heavy metals in to the environment poses a serious threat to the ecosystem owing to its non-degradability and indestructability. Physical and chemical techniques for the removal of heavy metals from industrial effluent is expensive and causes secondary pollution. On the other hand, biological processes using microorganisms play a vital role due to their large surface area to volume ratio, which increases the interactions with metal ions present in the environment. Here, we developed a third generation biological tool for the removal of heavy metal (copper) from the effluent through the biosynthesis of intracellular and surface displayed metallic proteins with novel metal co-ordination chemistry. We evaluated the cell viability for maximum heavy metal adsorption and metal tolerance of synthesized congener metallic proteins. Finally, to eliminate the cost associated with incorporation of metal binding aminoacid, we have introduced a genetic circuit in order to evolve a novel magnetotactic bacterium. The bioreactor studies of the consortia of metallic protein expressing cells immobilized on functionalized granular activated carbon revealed that 97% of copper was adsorbed from the industrial effluent. It is evident that the use of congener metallic proteins will be a futuristic approach for the treatment of wastewater facilitating environmental detoxification.