To properly assign biological effects and adverse effects of nanoproducts, their identity and integrity must be well defined and assured. Proper characterization of test materials is important to ensure that results are reproducible and to provide the basis for understanding that determines their biological effects. Scientists have many tools for studying the physical and chemical properties, e.g. size, shape, and surface properties of particulates, for quality control of established pharmaceutical products, however, it is rather difficult to measure many of these same properties for the emerging new dosage form, nanoproducts. There is growing consensus that a series of guidelines or recommended practices is necessary for basic characterization of nanoproducts. Complete characterization of nanoproducts includes size and size distribution, shape and other morphological features (e.g. crystallinity, porosity, surface roughness), chemistry of the material, solubility, surface area, state of dispersion, surface chemistry, and other physicochemical properties.
In addition, there exist uncertainties around the health and environment impact of nanoproducts. In this article, some of physical and chemical characteristics, analytical instruments for their measurement and, also, toxicological concerns of nanoproducts are reviewed.
Iodocoat® ointment containing iodine is an external preparation used in treatment of skin ulcers including decubitus, called pressure ulcers or bedsores. This ointment turns into a gel by absorbing exudation; consequently, it easily cleans wounds and also gradually releases Iodine to prevent infection. It is especially effective in the treatment of infected wounds by discharging copious exudation. Its basic ingredients are macrogol, carmellose sodium, polyacrylic moiety neutralizer, sugar, cross-linker and pH adjuster. The average of water absorption is 6.7 mL/g and the iodine cumulative release rate in 24 hours is 70%. Though the ointment turns into a gel by absorbing various amounts of water, the maximum gel strength is obtained by mixing ointment with water in the ratio of 1 to 1.5. This ointment continually releases iodine for over 24 hours and has a wide antibacterial spectrum.