Chemical Engineering / Kimya Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/14
Browse
2 results
Search Results
Conference Object Citation - Scopus: 4Effects of Surface Functional Groups on the Aggregation Stability of Magnetite Nanoparticles in Biological Media Containing Serum(Institute of Electrical and Electronics Engineers Inc., 2011) Wiogo, Hilda T. R.; Lim, May; Bulmuş, Volga; Amal, RoseSize stability of magnetite nanoparticles (MNP) with different surface functional groups in biological media was achieved by the addition of fetal bovine serum (FBS). The stability of the particles was attributed to the formation of protein coronas around the particles, which provides sufficient steric hindrance to prevent aggregation of the particles. The stability of different modified MNP were also studied in biological media containing bovine serum albumin (BSA) to further understand the stabilization mechanism. BSA was found to stabilize polyethyleneimine (PEI) modified MNP and polymethacrylic acid (PMAA) coated MNP, but not the bare MNP. These results indicate a difference in interactions between serum protein and the MNP that is govern by the type of functional groups on the MNP surface, with positively charged surface groups resulting higher protein adsorption and better stability. © 2011 IEEE.Article Citation - WoS: 55Citation - Scopus: 61Insight Into Serum Protein Interactions With Functionalized Magnetic Nanoparticles in Biological Media(American Chemical Society, 2012) Wiogo, Hilda T. R.; Lim, May; Bulmuş, Volga; Gutie´rrez, Lucía; Woodward, Robert C.; Amal, RoseSurface modification with linear polymethacrylic acid (20 kDa), linear and branched polyethylenimine (25 kDa), and branched oligoethylenimine (800 Da) is commonly used to improve the function of magnetite nanoparticles (MNPs) in many biomedical applications. These polymers were shown herein to have different adsorption capacity and anticipated conformations on the surface of MNPs due to differences in their functional groups, architectures, and molecular weight. This in turn affects the interaction of MNPs surfaces with biological serum proteins (fetal bovine serum). MNPs coated with 25 kDa branched polyethylenimine were found to attract the highest amount of serum protein while MNPs coated with 20 kDa linear polymethacrylic acid adsorbed the least. The type and amount of protein adsorbed, and the surface conformation of the polymer was shown to affect the size stability of the MNPs in a model biological media (RPMI-1640). A moderate reduction in r 2 relaxivity was also observed for MNPs suspended in RPMI-1640 containing serum protein compared to the same particles suspended in water. However, the relaxivities following protein adsorption are still relatively high making the use of these polymer-coated MNPs as Magnetic Resonance Imaging (MRI) contrast agents feasible. This work shows that through judicious selection of functionalization polymers and elucidation of the factors governing the stabilization mechanism, the design of nanoparticles for applications in biologically relevant conditions can be improved. © 2012 American Chemical Society.