Influence of Magnetic Micelles on Assembly and Deposition of Porphyrin J-Aggregates

March 24, 2020

Title

Influence of Magnetic Micelles on Assembly and Deposition of Porphyrin J-Aggregates

Author

Maria Angela Castriciano, Mariachiara Trapani, Andrea Romeo, Nicoletta Depalo, Federica Rizzi, Elisabetta Fanizza, Salvatore Patane, Luigi Monsù Scolaro

Year

2020

Journal

Nanomaterials

Abstract

Clusters of superparamagnetic iron oxide nanoparticles (SPIONs) have been incorporated into the hydrophobic core of polyethylene glycol (PEG)-modified phospholipid micelles. Two different PEG-phospholipids have been selected to guarantee water solubility and provide an external corona, bearing neutral ([email protected]) or positively charged amino groups ([email protected]). Under acidic conditions and with specific mixing protocols (porphyrin first, PF, or porphyrin last, PL), the water-soluble 5,10,15,20-tetrakis-(4-sulfonatophenyl)-porphyrin (TPPS) forms chiral J-aggregates, and in the presence of the two different types of magnetic micelles, an increase of the aggregation rates has been generally observed. In the case of the neutral [email protected], PL protocol affords a stable nanosystem, whereas PF protocol is effective with the charged [email protected] In both cases, chiral J-aggregates embedded into the magnetic micelles ([email protected]@micelles) have been characterized in solution through UV/vis absorption and circular/linear dichroism. An external magnetic field allows depositing films of the [email protected]@micelles that retain their chiroptical properties and exhibit a high degree of alignment, which is also confirmed by atomic force microscopy.

Instrument

FP-750, J-720

Keywords

Circular dichroism, Linear dichroism, Aggregation, Fluorescence, Nanostructures, Materials