文摘
In this work, we studied guest-host interactions between various dye molecules and the fifth-generation poly(propylene imine) (PPI-5) dendrimers in aqueous solutions using a surface plasmonresonance (SPR) sensor. The effect of the properties of guest and host molecules (e.g., charge and shape)and media (e.g., pH and ion strength) on affinity between guest and host molecules was investigated.Based on an immobilized homogeneous monolayer of PPI-5 dendrimer tethered to carboxyl-terminal self-assembled monolayers, the adsorption behavior of a group of dye molecules in PPI-5 was obtained. Resultsshow that the strong affinity of PPI-5 to Rose Bengal and erythrosine B is attributed to the good match incharge and shape between the cavities of the dendrimer and the dye molecules. Maximum adsorptionaround a pH value of 7 was observed. The kinetic behaviors of different dye molecules in dendrimers werealso studied. A fundamental understanding of guest-host interactions in dendrimers will guide the designof new-generation sensors and drug delivery carriers.