Synthesis of siloxane-based PAMAM dendrimers and luminescent properties of their lanthanide complexes

The 0.5–2 generations of siloxane-based PAMAM dendrimers with 1, 3-bis(3-aminopropyl) tetramethyldisiloxane (G0) as core unit were synthesized by two different methods. Their structures were characterized by FTIR, 1H NMR, 13C NMR, LC/MS, TGA, and DSC. Results show that method two is more suitable as its synthetic procedure is simple and it provides higher yield than method one. DSC analysis indicates that the introduction of the siloxane linkage into the interior of the dendrimers has significant effect on the flexibility of the dendrimer structures. Lanthanide complexes of the newly designed siloxane-based PAMAM dendrimers were obtained by complexing with Eu(III) and Tb(III), respectively. The luminescent properties of the complexes in the solution were investigated. Narrow-width red and green emissions were observed from the complexes of G0.5, G1.5, and G2.0, indicating intramolecular energy transfer process takes place between ligands and lanthanide ions.

Siloxane-based PAMAM dendrimers were synthesized and fully characterized. Results indicate that the siloxane linkage has significant effect on the flexibility of the dendrimer structures. Lanthanide complexes of the newly designed siloxane-based PAMAM dendrimers were obtained by complex with Eu(III) and Tb(III), and the luminescent properties of the complexes were investigated.Figure optionsDownload as PowerPoint slideResearch highlights
► Siloxane-based PAMAM dendrimers were synthesized by two different methods.
► The introduction of the siloxane linkage into the interior of the dendrimers has significant effect on the flexibility of the dendrimer structures.
► Narrow-width red and green emissions were observed for the complexes of G0.5, G1.5, and G2.0 with Eu(III) and Tb(III).