Chemistry Faculty Publications
Document Type
Article
Abstract
The interaction between self-aggregated porphyrins such as 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TPPS) and 5,10,15,20-tetrakis(4-phosphonatophenyl)porphyrin (TPPP), and a generation 5 (G5) PAMAM dendrimer template is governed by minute differences of porphyrin acido-basic properties. While at neutral pH both monomeric TPPS and TPPP form complexes with G5, decreasing pH did not lead to porphyrin ring protonation (pK(a) approximate to 5) but rather to the preferential formation of H-aggregates (probably H-dimers), most likely due to protonation of the G5. Upon further acidification of the solution, this face-to-face orientation of the porphyrin units is being converted to edge-to-edge aligned J-aggregates with a tightly defined structure. This process starts by protonation of the porphyrin ring at pH below 2.3 and 2.8 for TPPS and TPPP, respectively. The AFM imaging of porphyrin/G5 nanostructures obtained at pH 0.7 shows the formation of long nanorods of TPPS with partially aggregated G5 and small aggregates of TPPP connected to individual G5 molecules.
Copyright Statement
Publisher PDF
Repository Citation
Kubat, Pavel; Lang, Kamil; Janda, Pavel; and Anzenbacher, Pavel Jr., "Interaction Of Porphyrins With A Dendrimer Template: Self-aggregation Controlled By Ph" (2005). Chemistry Faculty Publications. 139.
https://scholarworks.bgsu.edu/chem_pub/139
Publication Date
10-2005
Publication Title
Langmuir
DOI
https://doi.org/10.1021/la051106g
Start Page No.
9714
End Page No.
9720