Abstract
Due to their unique size-dependent properties, nanoparticles (NPs) have many industrial and biomedical applications. Although NPs are generally characterized based on the size or morphological analysis, the mass of whole particles can be of interest as it represents the total amount of material in the particle regardless of shape, density, or elemental composition. In addition, the shape of nonspherical NPs presents a conceptual challenge, making them difficult to characterize in terms of size or morphological characteristics. Here, we used a novel nano-electro-mechanical sensor mass spectrometry (NEMS-MS) technology to characterize the mass distributions of various NPs. For standard spherical gold NPs, mass distributions covered the range from ∼5 to 250 MDa (8 to ∼415 attograms). Applying the density of gold (19.3 g/cm3) and assuming perfect sphericity, these mass measurements were used to compute the equivalent diameters of the NPs. The sizes determined agreed well with the transmission electron microscopy (TEM) imaging data, with deviations of ∼1.4%. Subsequently, we analyzed the mass distribution of ∼50 nm synthetic silicon dioxide particles, having determined their size by electron microscopy (SEM and TEM). Their estimated density was in line with the literature values derived from differential mobility analyzer and aerosol particle mass analyzer data. Finally, we examined the intact gold nanotetrapods and obtained a mass distribution revealing their controlled polydispersity. The presence of polyethylene glycol coating was also quantified and corroborated nuclear magnetic resonance observations. Our results demonstrate the potential of NEMS-MS-based measurements as an effective means to characterize NPs, whatever their composition, shape or density.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.