Paper Title
DIFFUSIVE GRADIENT IN THIN FILM AS A PROMISING TOOL FOR IN SITU ENVIRONMENTAL MONITORING: A REVIEW

Abstract
Over the last few decades, huge amounts of chemicals including polar organic compounds, and different types of heavy metals and metalloids have been discharged into aquatic and terrestrial environments. These chemicals can also impact the normal functioning of soil and crop yields, and stimulate hazardous effects on living organisms. Herein, the precise determination of the contaminants, their influence on environmental ecosystems, and subsequently design and development of new sampling techniques are the hot topics of research in the environmental field. The diffusive gradient in thin film (DGT) is one of the passive sampling techniques,initially reported in 1994 by Davison and Zhang for the sampling of inorganic compounds such as trace metals and metalloids or phosphorus, in aquatic conditions. The binding gels play a key role in the successful deployment of DGT; hence, it is essential to choose the binding gels with an adsorption capacity and rate to cope with the requirements of the DGT principle.This review focuses on the study of different novel binding gel materials to be employed in DGT for improved efficiency(e.g., ensuring deployment time that can be freely reduced or increased depending on the purpose of application). Recently a variety of nanomaterials and metal-organic frameworks (MOF) compounds such as nanofibers, graphene, nanoscale metal oxides, carbon nanotubes fullerenes, nanoparticles, and quantum dots haveshown great promises for monitoring various contaminants in water and wastewater treatment processes.The various field deployment outcomesshow that the DGT is notsignificantly influenced by specific ranges ofionic strength,pH,and flow rates in ambient environmental media conditions, indicating that the DGThas great potential for monitoring various types of contaminants with high accuracy. Keywords - Passive Sampler: Quantitative Monitoring; Binding Gels: Metal-Organic Framework: Bioavailability