Optimizing Instrument Operation and Data Processing for Single Particle Inductively Coupled Plasma Mass Spectrometry Measurement of Gold Nanoparticles

J. Liu, K.E. Murphy, R.I. MacCuspie, M.R. Winchester
National Institute of Standards and Technology, US

Keywords: single particle ICP-MS, gold nanoparticles, characterization


In recent years, inductively coupled plasma mass spectrometry (ICP-MS) operated in time-resolved analysis (TRA) mode has merged as a promising analytical tool capable of both sizing and counting metal containing nanoparticles in aqueous suspensions. In this study, the performance of nanoparticle detection using SP-ICP-MS was investigated systematically with the purpose of developing a robust methodological approach for simultaneously characterizing and quantifying the size and concentration of nanoparticles in aqueous suspensions. Seven monodisperse spherical gold nanoparticles (AuNPs, 10 nm to 200 nm in diameter) were used as model materials. Instrument operating parameters, test solution concentration and data processing were optimized for accurate size and concentration measurement. We show that incomplete and coincident particle pulses can be identified among time-resolved intensity data, enabling data correction Particle size distributions were derived by a previously established method3 with modification using soluble standard calibration, and were compared with other sizing techniques: transmission electron microscopy (TEM), scanning electron microscopy (SEM) and dynamic light scattering (DLS). In addition, size measurements were successfully performed on AuNP mixtures.