Effects of polyethylenimine on the dispersibility of hollow silica nanoparticles

Abstract

In this study, two different methods were applied to disperse hollow silica nanoparticles (HSNP); one employed polyethylenimine (PEI) as the dispersant during the synthesis processes for preparing HSNP, while the other added PEI into suspensions of the prepared HSNP and used milling treatment to achieve the desired dispersion. It was found that adding PEI during the synthesis process of HSNP had no noticeable improvement in the dispersion, while adding PEI into suspensions of the prepared HSNP and utilizing milling treatment resulted in remarkable dispersion improvement. Therefore, the latter was chosen as the method in dispersing HSNP suspensions. The adsorption of PEI on the surface of HSNP and the stability of the aqueous suspensions was investigated. The results indicated that the adsorption of PEI on the surface of HSNP would increase the repulsive energy among particles, hence reducing the agglomeration of HSNP and improving the stability of the aqueous suspensions. The change of HSNP's f potential after adding PEI and the relationship between the adsorbed amount of PEI and pH were also investigated.

Reactivity of NK Cells Against Ovarian Cancer Cells Is Maintained in the Presence of Calcium Phosphate Nanoparticles

“…Basically, in biological fluids cellular uptake of CaP-NPs is dependent on size, charge and surface characteristics (8,32). So, different components like PEI, silica shell or specific antibodies determine state of aggregation, absorption of proteins and cellular uptake (33)(34)(35). An alternative explanation could be the targeting-effect by Cetuximab in CaP-S-C NPs, which has been already described in principle (36).…”