Silica particles containing a layer of β-cyclodextrins were synthesized using a modified method of Armstrong (1985). The modified silica particles were extensively characterized to both the presence and amount of β-cyclodextrin introduced onto the surface. Raman confirmed that β-cyclodextrin was introduced onto the particle. The combination of thermogravmetric analysis (TGA) and direct pyrolysis mass spectroscopy were used to determine the amount and the chemical composition of organic material present on the silica, respectively. The two methods confirmed that β-cyclodextrin was successfully introduced in amounts comparable to earlier literature values. The values obtained by TGA were compared to amounts found by elemental analysis and XPS. The elemental analysis and TGA found the same amount of β-cyclodextrin, while the XPS values were in the region of 1.5 times higher. This suggests a heterogeneous distribution of the β-cyclodextrin on the silica particles.
Surface and Interface Analysis, Vol. 43, no. 5 (May 2011), pp. 884–892