Nowadays a wide variety of synthesis techniques are utilized to produce nanoporous materials. In this review, we summarize the general principles of templated synthesis using various types of templ...

Templated Synthesis for Nanoarchitectured Porous Materials

Synthesis of spherical mesoporous silica nanoparticles with nanometer-size controllable pores and outer diameters

Adsorption of heavy metals on functionalized-mesoporous silica: A review

With the development of nanotechnology, nanomaterials are being widely used in many industries as well as in medicine and pharmacology. Despite the many proposed advantages of nanomaterials, increasing concerns have been expressed on their potential adverse human health effects. In recent years, application of nanotechnology in medicine has been defined as nanomedicine. Techniques in nanomedicine make it possible to deliver therapeutic agents into targeted specific cells, cellular compartments, tissues, and organs by using nanoparticulate carriers. Because nanoparticles possess different physicochemical properties than their fine-sized analogues due to their extremely small size and large surface area, they need to be evaluated separately for toxicity and adverse health effects. In addition, in the field of nanomedicine, intravenous and subcutaneous injections of nanoparticulate carriers deliver exogenous nanoparticles directly into the human body without passing through the normal absorption process. These nanoparticulate carriers themselves may be responsible for toxicity and interaction with biological macromolecules within the human body. Second, insoluble nanoparticulate carriers may accumulate in human tissues or organs. Therefore, it is necessary to address the potential health and safety implications of nanomaterials used in nanomedicine. Toxicological studies for biosafety evaluation of these nanomaterials will be important for the continuous development of nanomedical science. This review summarizes the current knowledge on toxicology of nanomaterials, particularly on those used in nanomedicine.

Toxicology of Nanomaterials Used in Nanomedicine

Recent progress on desiccant materials for solid desiccant cooling systems

Synthesis of ordered large pore SBA-15 spherical particles for adsorption of biomolecules.

Thermodynamics of Water Interaction with Human Stratum Corneum I: Measurement by Isothermal Calorimetry

Background/purpose: The water content of skin has a significant impact on skin properties; sufficient hydration is necessary to keep the skin supple, flexible, and smooth. To understand more completely the water retention properties of the human skin barrier, physical macroscopic properties must be related to the structural organization of the stratum corneum (SC). Water, lipids, and natural moisturizing factor (NMF) influence the molecular structures that affect the properties of SC, including water sorption and binding enthalpy. In the research reported here, isothermal microcalorimetry was used to study the interaction of water vapor with isolated human SC in intact, delipidized, and water-washed delipidized forms to identify the influences of the principal components of SC on water sorption. The calorimetric data are interpreted in conjunction with spectroscopic results to identify the conformational changes in keratins induced by lipid and NMF removal and to assess the influence of these changes on water binding in SC.



Methods: Isothermal calorimetry was used to measure the integral heat of water vapor sorption on intact, delipidized, and water-washed delipidized human SC at 32 °C as a function of relative humidity using back and thigh skin from three donors. Calorimetric measurements were combined with water vapor sorption measurements to determine the differential thermodynamic properties of these systems. Attenuated total reflection–Fourier transform infrared spectroscopy was used to investigate effects of extraction on protein secondary structure.



Results: The magnitudes of the differential enthalpy, entropy, and free energy were greatest for intact SC and least for water-washed delipidized SC. Water sorption followed a similar trend. Delipidization led to a significantly reduced binding enthalpy at low water content; water washing the delipidized SC had only a small additional effect on binding enthalpy. Delipidization converts a fraction of keratin α-helixes to turns and random coils, while water sorption converts a fraction of keratin α-helixes to β-sheets, turns, and random coils.



Conclusions: The results of this study are consistent with a water sorption model in which keratin–keratin hydrogen bonds are replaced by keratin–water hydrogen bonds. Delipidization reduces the fraction of dry keratin that is in the α-helix conformation, suggesting that lipids hold the keratins in a conformation conducive to optimal hydration.

Santosh Yadav

Papers

Synthesis of ordered large pore SBA-15 spherical particles for adsorption of biomolecules.

Thermodynamics of Water Interaction with Human Stratum Corneum I: Measurement by Isothermal Calorimetry

Comparative thermodynamic and spectroscopic properties of water interaction with human stratum corneum.

Thermodynamics of water interactions with human stratum corneum. II.: Interpretation via the Guggenheim–Anderson–deBoer isotherm

The energetics of water interactions with adult and neonatal skin