Int. j. mass spectrom. Int. j. mass spectrom. An approach to the natural and engineered nanoparticles analysis in the environment by inductively coupled plasma mass spectrometry Jiménez M. S. Universidad de Zaragoza Gómez M. T. Universidad de Zaragoza Bolea E. Universidad de Zaragoza Laborda F. Universidad de Zaragoza Castillo J. Universidad de Zaragoza 2011 research-article