Editor’s Choice – “Solid State Concerns During Drug Discovery and Development: Thermodynamic and Kinetic Aspects of Crystal Polymorphism and the Special Cases of Concomitant Polymorphs, Co-Crystals and Glasses”

Journal: Current Drug Discovery Technologies

Author(s): Daniel P. Otto, Melgardt M. De Villiers

Graphical Abstract:

Abstract:

During drug discovery and development the thermodynamics and kinetics of crystal form transitions must be studied and the fundamental properties of polymorphs must be identified. However, despite the accumulation of knowledge and experimental evidence that support the understanding of crystallization, its predictability still presents significant challenges. With the continuous development of new drug delivery technologies, even more complex situations arise such as difficult cases of polymorph selection, co-crystallization of different molecules, and manipulation of the crystallization environment for example amorphous solids. This review covers some fundamental thermodynamics and kinetics of simple system, before the discussions consider at these special cases and how the manipulation of thermodynamic and kinetic processes has increased our knowledge, understanding and application of crystallization science during the drug development process.

Read more here: http://www.eurekaselect.com/147852

Open Access Articles – “A Novel Material for Removal of Organochlorine Pesticides from Aqueous Environment: Kinetics and Thermodynamics Investigations”

Journal: Current Environmental Engineering

Author(s): Abdul Ghaffar, Azhar Mashiatullah and Naveed Iqbal

ceeAbstract: Chitosan Grafted Silica (CGS) material was prepared by using tetraethyl-orthosilicate as grafting and/or cross linking agent. The structure of the material was characterized by SEM (Scanning Electron Microscopy), FTIR (Fourier transform infrared Spectroscopy), and BET (Brunauer, Emmett and Teller) analysis. The higher sorption potential of synthesized material for organo-chlorine pesticides (OCPs) like DDT and DDE was attributable to its large surface area, porous rigid structure and active sites such as –OH, –NH2, and –CONH2. Most removal of DDT (94±2.9%) and DDE (86 ±1.8%) was achieved at 40°C and pH 6 with agitation of 2 and 3 hours, respectively. The thermodynamics data suggested an endothermic, spontaneous and higher stable sorption process with no structural changes at the solid-solution interface. The ΔG value was increased with an increase in temperature up to 40°C, indicating a greater driving force ensuing a higher sorption capacity. The co-efficient of correlation (R2) suggested that the sorption data was best fitted in Freundlich isotherm rather than the Langmuir isotherm, indicating a multilayer sorption. The Freundlich sorption isotherm proposed a favorable sorption of DDT as compare to DDE. The developed method was applied to real industrial waste at laboratory level. The experimental data revealed that developed method might be employed for the removal of DDT and DDE from aqueous industrial effluents before discharging them into water bodies.

Read more here: http://benthamscience.com/journals/current-environmental-engineering/volume/1/issue/2/page/100/