In Vivo Toxicity of Intravenously Administered Silica and Silicon Nanoparticles

Abstract

Both silicon and silica nanoparticles (SiNPs and SiO2NPs, respectively) are currently considered to be promising carriers for targeted drug delivery. However, the available data on their in vivo toxicity are limited. The present study was aimed at investigation of SiNP and SiO2NP (mean diameter 10 and 13 nm, respectively) toxicity using both morphological and functional criteria. Hematological and biochemical parameters were assessed in Sprague-Dawley rats 5, 21 and 60 days after administration of NPs. Inner ear function was determined using otoacoustic emission testing at 21 and 60 days after infusion of NPs. Furthermore, the histological structure of liver, spleen and kidney samples was analyzed. Intravenous infusion of SiNPs or SiO2NPs (7 mg/kg) was not associated with significant changes in hemodynamic parameters. Hearing function remained unchanged over the entire observation period. Both inter- and intragroup changes in blood counts and biochemical markers were non-significant. Histological findings included the appearance of foreign body-type granulomas in the liver and spleen as well as microgranulation in the liver after administration of NPs. The number of granulomas was significantly lower after administration of SiNPs compared with SiO2NPs. In conclusion, both tested types of NPs are relatively biocompatible nanomaterials, at least when considering acute toxicity.

Silicon-containing nanocarriers for targeted drug delivery: synthesis, physicochemical properties and acute toxicity

“…We have previously shown that SiO 2 NPs are non-toxic during acute intravenous administration (Galagudza et al, 2010a,b). However, a single intravenous injection of SiO 2 NPs resulted in their accumulation in the organs of the reticuloendothelial system, and caused the formation of multiple granulomas in the liver and spleen (Ivanov et al, 2012). Although some studies have demonstrated the complete biodegradation of SiO 2 NPs (Malvindi et al, 2012), most studies, in agreement with our data, reveal a delayed pattern of SiO 2 NP biodegradation (Nishimori et al, 2009;Xie et al, 2010).…”

“…When administered intravenously, SiO 2 NPs were shown to accumulate in reticuloendothelial system, particularly in the liver and spleen, resulting in the formation of foreign body-type granulomas (Ivanov et al, 2012). Therefore, there is great interest surrounding organomodified silica NPs, which combine the properties of organic and inorganic substances.…”

Targeted drug delivery using genetically engineered diatom biosilica

“…The accumulation of both targeted and non-targeted nanoparticles in the liver and kidney has also been reported in previous studies 37,38 . The liver accumulation of silica is expected as a result of particle uptake by macrophages in the reticuloendothelial system 39 .…”

Engineered Nanomaterial Impact in the Liver following Exposure via an Intravenous Route–The Role of Polymorphonuclear Leukocytes and Gene Expression in the Organ

“…These doses are not dissimilar to other studies in which animals have been exposed to NMs via an IV route [21,22]. The findings in this study suggest that neutrophils are involved in the organs immunity to the foreign nanomaterials.…”