Chemistry Faculty Publications
Document Type
Article
Abstract
Cationic alkyl/arylphosphonium meso-tetratolylporphyrins aggregate in an aqueous solution to form H-aggregates, J-aggregates, and long-range assemblies. The ratio between the monomer and various types of aggregates can be controlled by the substitution in the phosphonium units and by the ionic strength. A trimethylphosphonium derivative is predominantly monomeric, dimethylphenylphosphonium forms monomers as well as low-molecular-weight H- and J-aggregates, triphenylphosphonium forms mainly H- and J-aggregates, and tri(n-butyl)phosphonium forms mainly long-range assemblies. Porphyrin monomers associate with calf thymus DNA (binding constant Kb approximate to 10(7) M-1) and oligonucleotides (K-b approximate to 10(5-)10(6) M-1). The large size of the meso-substituents prevents the intercalation between base pairs. All phosphonium porphyrins described in this study were found to bind to the phosphate backbone of a nucleic acid with a significant preference for A-T base pair sequences. Porphyrin aggregates formed in the solution deposit readily on the surface of the DNA and oligonucleotides without changing their structure and size. Porphyrin monomers bound to DNA and nucleotides have photophysical properties (higher quantum yield of triplet states and singlet oxygen) different from those of porphyrin aggregates.
Copyright Statement
Publisher PDF
Repository Citation
Kubat, Pavel; Lang, Kamil; Kral, Vladimir; and Anzenbacher, Pavel Jr., "Preprogramming Of Porphyrin-nucleic Acid Assemblies Via Variation Of The Alkyl/aryl Substituents Of Phosphonium Tetratolylporphyrins" (2002). Chemistry Faculty Publications. 107.
https://scholarworks.bgsu.edu/chem_pub/107
Publication Date
7-2002
Publication Title
Journal Of Physical Chemistry B
DOI
https://doi.org/10.1021/jp014405x
Start Page No.
6784
End Page No.
6792