An ICP-MS-based platform for release studies on silver-based nanomaterials

Engineered nanoparticles are being incorporated into different products and nanocomposites. The release of these nanoparticles, as well as other derived species, can subsequently lead to consumer and environmental exposure, being a relevant factor for risk assessment. The need for analytical methods for the detection, characterization and quantitation of these released species under relevant conditions becomes evident. In this work, a platform of methods based on the use of inductively coupled plasma mass spectrometry (ICP-MS) is proposed to obtain information about the release of silver from silver based nanocoatings and nanocomposites. The sensitivity and element specific response of conventional ICP-MS is complemented by the use of the technique in single particle mode and in combination with ultrafiltration and asymmetrical flow field flow fractionation. By using these three methods, information about the release of both dissolved and particulate forms of silver, as well as the size of the nanoparticles, can be obtained under a variety of scenarios at concentrations down to 0.1 mu g L-1 and a nanoparticle diameter of 5 nm. The feasibility of the platform was checked through a number of paradigmatic cases.