Solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry to monitor the biodistribution of gold nanoparticles in mice tissue after intravenous administration

Abstract

In this work, the capabilities of solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry (GFAAS) for the direct determination of the Au content in different body compartments of mice that were previously exposed to Au nanoparticles (AuNP) capped with different compounds have been investigated. It was concluded that this technique offers interesting features for this type of application, permitting the fast (approx. 15 min per sample) and simple analysis of these materials with minimal sample pretreatment, ensuring a similar analytical response regardless of the functionalizing compound chosen for the NP. The potential of this technique for resolving spectral overlaps with PO molecular lines is shown to be essential to ensure interference-free results for those samples containing only a few tens of ng g⁻¹ of Au (brain tissues), such that accurate results can be obtained using straightforward calibration against aqueous standards even in circumstances that would be very unfavorable for traditional line source GFAAS instrumentation. A detection limit of 5 pg (2 ng g⁻¹) is reported. The usefulness of the method proposed to obtain meaningful conclusions regarding i) the temporal biodistribution of small (approx. 2 nm in diameter) AuNP in mouse organs, and ii) the different behavior observed depending upon the functionalizing compound used (glucose or lactose) is also demonstrated.