Separació de nanopartícules de plata de plata iònica per a la seva determinació per espectroscòpia d’emissió atòmica mitjançant plasma induït per alta freqüència (ICP-OES): estudi dels paràmetres que afecten a la separació per bescanvi iònic

Abstract

In the last decades, nanotechnology has evolved so much that the use of nanoparticles has increased a lot. Thanks to its properties, nanoparticles have a wide application in regular consumer products as well as in medicine, industry, catalysis, construction, etc. After its use, a large number of nanoparticles reach the environment, so that they can be found in different types of soils, water and even in the air. Thanks to various studies carried out in recent years, it has been shown that nanoparticles interact with the environment and, therefore, with the living beings that live there. This interaction depends on the characteristics of nanoparticles as well as those of the environment and can lead to various problems or diseases. It also has been observed that the properties and behaviour of nanoparticles are different from the element in solution, so that it is interesting to study the two species separately. In this project, we try to find a simple method that can separate the silver nanoparticles of ionic silver quantitatively. Thanks to the found literature, it is expected that a solid-liquid extraction can be carried out by means of an ion exchange resin since ionic silver is positively charged and nanoparticles are neutral or slightly positive. Although it is expected that this extraction would be simple, it is observed that there is a high amount of factors that affect the interaction with the resin and, therefore, prevent the separation of the two forms of silver. Some of these factors, which are common in natural waters, are studied and the method is applied to a sample of a river water. However, in all cases the separation has not been possible. A determination by atomic spectroscopy it also has been made through ICP-OES and ICP-MS. While ICP-OES technique can not discriminate between ionic silver and nanoparticles, the method used in ICP-MS, called single particle, does allow it. In addition, the particle size and the nanoparticles percentage present in the suspension can also be determined using this last technique