Aggregation behavior of the template-removed 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin chiral array directed by poly(ethylene glycol)-block-poly(L-lysine).

ABSTRACT

Complexation between 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TPPS) and poly(ethylene glycol)-block-poly(L-lysine) (PEG-b-PLL) was performed via electrostatic interaction. Two kinds of primary arrays of TPPS with different supramolecular chirality induced by PLL were obtained in the resultant complex by inverting the mixing procedure of the two components. These arrays could be displaced by poly(sodium-p-styrenesulfonate) (PSS) from the chiral PLL template through competitive electrostatic complexation, and then PSS formed a polyion complex micelle with PEG-b-PLL. The template-removed TPPS arrays preserved their induced chirality and served as primary subunits for the secondary aggregation of TPPS. The morphology of the secondary aggregates was strongly dependent upon the asymmetric primary supramolecular arrangement of TPPS. The rodlike nanostructure that was ∼200 nm in length was composed of the primary arrays that showed opposite exciton chirality between the J- and H-bands. In contrast, the micrometer-sized fibrils observed were composed of the arrays with the same exciton chirality at the J- and H-bands.