Evaluation of Bioaccumulation Kinetics of Gold Nanorods in Vital Mammalian Organs by Means of Total Reflection X-Ray Fluorescence Spectrometry

Abstract

This work presents the first application of total-reflection X-ray fluorescence (TXRF) spectrometry, a new and powerful alternative analytical method, to evaluation of the bioaccumulation kinetics of gold nanorods (GNRs) in various tissues upon intravenous administration in mice. The analytical parameters for developed methodology by TXRF were evaluated by means of the parallel analysis of bovine liver certified reference material samples (BCR-185R) doped with 10 μg/g gold. The average values (n = 5) achieved for gold measurements in lyophilized tissue weight were as follows: recovery 99.7%, expanded uncertainty (k = 2) 7%, repeatability 1.7%, detection limit 112 ng/g, and quantification limit 370 ng/g. The GNR bioaccumulation kinetics was analyzed in several vital mammalian organs such as liver, spleen, brain, and lung at different times. Additionally, urine samples were analyzed to study the kinetics of elimination of the GNRs by this excretion route. The main achievement was clearly differentiating two kinds of behaviors. GNRs were quickly bioaccumulated by highly vascular filtration organs such as liver and spleen, while GNRs do not show a bioaccumulation rates in brain and lung for the period of time investigated. In parallel, urine also shows a lack of GNR accumulation. TXRF has proven to be a powerful, versatile, and precise analytical technique for the evaluation of GNRs content in biological systems and, in a more general way, for any kind of metallic nanoparticles.

Gold Nanocomposite Bioink for Printing 3D Cardiac Constructs

“…Previous studies showed an almost immediate clearance of the GNR from the circulation after the administration. In blood serum, GNR immediately forms a protein corona, causing rapid recognition and internalization by components of the reticuloendothelial system and mainly accumulates in liver . These studies revealed that the accumulated GNRs in a healthy liver did not cause significant hepatotoxicity as evidenced by biochemical and histological measurements, even at high doses (4 µg g −1 by weight) of systemically administrated GNR.…”

“…One crucial factor that requires further study is the determation of the fate of GNRs in the host system. In most studies, GNRs were systemically administrated and subsequently distributed in organs . For the implanted cardiac construct, however, it has been speculated that the GNRs could be mainly internalized by the local cardiac cells after the degradation of biomaterial matrix and only a small amount of them may enter circulation system.…”

“…However, potential harm could be induced in clinically relevant settings of liver injury. [25b] The dose of GNR in our printed construct was deemed safe; however, particular caution would be required if liver diseases are concomitantly present in clinical scenarios.…”

Total reflection X-ray fluorescence

“…Biological and clinical materials generally need to be pretreated to remove the organic matrix which would increase the background signal and thus worsen the detection limits. Common pretreatment methods are ashing, acid digestion, or purification using chromatographic methods [42][43][44][45][46][47][48][49][50]. Mineral oil, vegetable oil or fatty acid containing samples like creams and lotions can be diluted with a solvent or if necessary subjected to cold oxygen plasma ashing to remove excess carbon.…”

2015 Atomic Spectrometry Update – a review of advances in X-ray fluorescence spectrometry and their applications

“…The authors simulated and investigated experimentally the sputter yield of ZnO and GaAs nanowires, which were implanted with energetic Mn ions at room temperature. Fernandez-Ruiz et al 408 applied TXRF spectrometry to the evaluation of bioaccumulation kinetics of gold nanorods (NR) in vital mammalian organs. A clearly enhanced sputter yield for the irradiated nanowires compared with bulk was observed, which was also corroborated by simulations showing a maximum if the ion range matched the nanowire diameter.…”