Differential Perturbation of the Protrotropic Equilibrium of a Biological Photosensitizer within Bile Salt Aggregates of Varying Hydrophobicity: A Fluorimetric Investigation

Abstract

The present work reveals the binding interactions of a credible cancer cell photosensitizer, harmane (HM), with some selected bile salt aggregates of dissimilar hydrophobicity viz. sodium deoxycholate (NaDC), sodium cholate (NaC) and sodium taurocholate (NaTC). The explicit variation of the prototropic equilibrium of the photosensitizer both in the ground and excited state has been utilized to scrutinize the interaction phenomena. Differential modulation in the prototropic equilibrium of HM in the aforesaid aggregates has been explained on the basis of the structural dissimilarities of the bile salt monomers. The contrived hydrophobic surroundings provided by the aggregates have been reflected on the spectroscopic results, especially in the time-resolved fluorescence and the rotational dynamical behavior of the molecule of interest. Slow solvent reorientation time with regard to the lifetime of HM proliferated by the red-edge effect in two specific bile salts namely NaC and NaTC, whereas its absence in NaDC aggregates has also been elucidated on the basis of accessibility of the solvent molecules within the aggregates.

Co‐Assembly of Peptide with G‐Quadruplex DNA: A Strategic Approach to Develop Anticancer Therapeutics

“…The FA values were found to increase upon gradual addition of G4 DNA indicating the reduction in molecular mobility of the peptide in presence of G4 DNA which further supports the co-assembly phenomenon between peptide and G4 DNA. [15] The FA values of peptide in presence of dsDNA and ssDNA have also been checked. Noticeably, in presence of ds and ssDNA, the changes in FA values were small and irregular (Figure S8).…”