Conjugation with L,L-diphenylalanine Self-Assemblies Enhances In Vitro Antitumor Activity of Phthalocyanine Photosensitizer.

We present the synthesis and characterization of new peptide conjugates obtained by hierarchical co-assembly of L,L-diphenylalanine (FF) and zinc phthalocyanine complexes (ZnPc) in water. Self-assembly capabilities under defined conditions were investigated by scanning electron microscopy, and photophysical properties were evaluated using UV-Vis and fluorescence spectroscopy. AFM observations demonstrated that these ZnPcs form different highly ordered arrays on the crystalline faces of the FF microplates and that surface roughness significantly changes with the presence of differently substituted phthalocyanine units.

N-pentyl-nitrofurantoin induces apoptosis in HL-60 leukemia cell line by upregulating BAX and downregulating BCL-xL gene expression.

Background: Nitrofurantoin is a nitroderivative antibiotic that has bactericidal activity against pathogens causing urinary tract infection. A few studies have reported that nitrofurantoin has cytotoxic activity against cancer cells; however, nitrofurans remain a poorly explored class of compounds with respect to their anticancer potential. The aim of this study was to investigate the anticancer effects of a nitrofurantoin derivative, n-pentyl-nitrofurantoin (NFP), on HL-60 leukemia cells.

The role of water and structure on the generation of reactive oxygen species in peptide/hypericin complexes.

Hybrid associates formed between peptide assemblies and fluorophores are attractive mainly because of their unique properties for biomedical applications. Recently, we demonstrated that the production of reactive oxygen species (ROS) by hypericin and their stability in excited states are enhanced upon conjugation with l,l-diphenylalanine microtubes (FF-MNTs). Although the detailed mechanisms responsible for improving the photophysical properties of ROS remain unclear, tentative hypotheses have suggested that the driving force is the growth of overall dipolar moments ascribed either to coupling between aligned H2O dipoles within the ordered structures or to the organization of hypericin molecules on peptide interfaces.

Structural and photophysical properties of peptide micro/nanotubes functionalized with hypericin.

Hypericin is a photosensitizer with promising applications in photodynamic therapy (PDT) for cancer and infectious diseases treatments. Herein, we present a basic research study of L-diphenylalanine micro/nanotubes (FF-NTs) functionalized with hypericin. The system has special properties according to the hypericin concentration, with direct consequences on both morphological and photophysical behaviors.