Selective Cytotoxicity of Counterion-Conjugated Charged Iron Oxide Nanoparticles: A Study with Lymphoblastoid Raji Cells

The cytotoxicity of counterions-conjugated charged iron oxide nanoparticles (IONPs) was studied with lymphoblastoid Raji cells and was compared with peripheral blood lymphocytes.IONPs were coated either with tri-potassium citrate (TKC), or with cetylpyridinium chloride (CPC).TKC coated IONPs were negatively charged and K + counterions conjugated nanoparticles, and CPC coated IONPs were positively charged Cl -counterions conjugated nanoparticles.The cells were incubated with IONPs at 37 °C for 24 h and the cytotoxicity was studied by measuring the cell viability using MTT and LDH assays.The cytotoxicity of IONPs was further assessed through DNA fragmentation assay.Morphology of Raji cells was also observed by TEM.We have used a modified membrane lysis model to understand the cell death via cell membrane lysis due to counterions diffusion upon binding of IONPs.