Bovine serum albumin (BSA)

Abstract

Gold nanoparticles (AuNP) have become a tool of great interest due to its low reactivity and biocompatibility, making it a suitable material for constructing micro and nanoparticles. AuNPs can be used for various applications such as drug delivery, gene delivery, and bioimaging. This is possible because AuNPs can be functionalized with a coat, which allows the particle to take on the properties of the coat. The coating material used in this study is Bovine Serum Albumin (BSA), which has been previously shown to be biocompatible. In order to determine whether BSA-coated AuNPs (AuNP,BSA) can induce an adverse response, toxicity assessments of the AuNP,BSA were performed using zebrafish (Danio rerio) embryos. Zebrafish embryos were chosen as a model for toxicity assessments because of their sensitivity to toxic substances and their rapid development. Furthermore, the Zebrafish’s semi-transparent body allows for ease of observation of physiological changes. In addition to the toxicity assessment, Q-PCR and Cytokine assay were performed to assess any changes in IL-6 and TNF-α levels in order to determine if exposure to the AuNPs causes an inflammatory response.In this investigation, it was found that uncoated AuNPs exhibited little to no toxic effect on zebrafish embryos after 72 hours of exposure, while AuNP,BSA exerted some toxic effect. Q-PCR results of the zebrafish IL-6 and TNF-α showed that exposure to AuNPs slightly reduced IL-6 mRNA levels, while TNF-α levels did not differ from control. Exposure to AuNP,BSA also slightly reduced IL-6 mRNA levels. However, exposure to AuNP,BSA increased TNF-α mRNA levels. In addition, MTT assay was performed on mouse monocyte cell line RAW264.7 and human fibroblast cell line Wi-38 to determine if the AuNPs have any toxic effects in vitro. Results indicated that cells were viable after 24-hour exposure to up to 100 μM AuNP or AuNP,BSA. Furthermore, the cytokine assay for IL-6 and TNF-α showed that exposure to 100 μMAuNP or AuNP,BSA increased TNF-α secreted by RAW264.7, although cells exposed to AuNP,BSA secreted higher levels of TNF-α. However, cells exposed to either nanoparticle did not produce any IL-6. Additionally, a cytokine assay was performed after 6 hour exposure to the equivalent amount of BSA used to make a 100 μM AuNP,BSA solution to determine if BSA alone affected cytokine levels. Results showed that cells exposed to BSA alone produced greater levels of IL-6 and TNF-α compared to the control.