SiNPs are being formulated for potential drug delivery and for imaging and diagnostic applications in the CNS because they are considered to be more biocompatible than are other imaging NPs, such as quantum dots, which may contain toxic metals such as cadmium and mercury (Bharali et al.
We synthesized the SiNPs used in this study using the Stober method, which is known to generate amorphous SiNPs of a controlled size (Stober et al.
The dansylamide-embedded SiNPs were also characterized before treatment.
Microglia were exposed to SiNPs for 24 hr before being assayed.
We exposed primary microglia to various concentrations of SiNPs for 24 hr.
We examined whether SiNPs are cytotoxic to microglia, by measuring cell viability using the MTS assay.
To determine whether SiNPs can alter phagocytic activity, we exposed primary microglia to SiNPs for 24 hr before the addition of fluorescent polystyrene microspheres, which are commonly used to assess phagocytic activity.
Although cell viability was not altered by SiNPs, we were interested in determining whether SiNPs could induce the production of intracellular ROS and RNS.
To determine if exposure to SiNPs can induce an inflammatory response in primary microglia, we measured the levels of the proinflammatory genes TNF-[alpha] and COX-2 using qRT-PCR.
We examined the effect of SiNPs on the release of inflammatory cytokines, using Luminex technology, which can simultaneously measure 10 different cytokines.
In this article we provide in vitro evidence for the effects of SiNPs on primary microglia from rat brain.
4] [micro]g/mL), the SiNPs did not appear to be localized in phagocytic vacuoles but were dispersed throughout the cytoplasm.