Interaction of Human Serum Albumin with Novel 3,9-Disubstituted Perylenes

Abstract

Human serum albumin (HSA) has been used as a model for the binding of a number of different ligands, including polyaromatic hydrocarbons, to proteins. In this case we have investigated the interaction of HSA with a novel set of perylene derivatives. Di-substituted perylene analogues have been synthesized as potentially useful organic photovoltaic materials. Their photophysical properties may make them viable for fuel cell applications too. However, these molecules are poorly soluble especially in aqueous solvents. Binding to water-soluble proteins may provide a way to solubilize them. At the same time one can study whether the photophysical processes initiated by the irradiation of a perylene ligand can cause conformational changes to the host protein. With the present study we demonstrated that of the three perylene derivatives investigated only one, the dimethoxy analogue, has a significant affinity for HSA at a binding site near the bottom of the central cleft (in proximity of the Trp214 residue). The small affinity prevents any significant photoinduced changes to occur in the protein.

In vitro Analysis of the Interaction between Human Serum Albumin and Semi‑Synthetic Clerodanes

“…Figure 3) did not show any variation inside the experimental error, indicating that the fluorescence quenching mechanism is static. 29 On the other hand, in the presence of PHDCTN (τ 1 = 1.42 ± 0.11 and τ 2 = 5.42 ± 0.10, χ 2 = 1.316, Figure 3) the time-resolved fluorescence decay changed significantly confirming that, in this case, in addition to the static mechanism there is the presence of a dynamic fluorescence quenching mechanism.…”

“…[29][30][31][32] It is worth to note that results from the literature indicate that t-DCTN shows a much weaker binding ability for serum albumin than MHDCTN and PHDCTN. 13 Since the evaluation of the binding parameters between serum albumin and potential drugs is important to understand its distribution in the human plasma to body tissues and organs, the obtained binding ability between HSA:MHDCTN and HSA:PHDCTN suggests a decrease in the concentration of free molecules in the human plasma.…”

Effects of Visible‐Light Irradiation of Protoporphyrin IX on the Self‐Assembly of Tubulin Heterodimers

“…This contribution, because it is elastic, is recorded only in the early channels of the decay in the region overlapped with the profile of the excitation source [27] . Since PPIX quenches the emission of the Trp residues throughout the entire decay window, the combination of the two effects often causes a relative increase of scattering which in turn produces an apparent faster decay.…”

Characterization of novel perylene diimides containing aromatic amino acid side chains

“…Solubility of these compounds in moderately to highly polar solvents was certainly much larger than for the 3,9-disubstituted perylenes studied previously [15] which did not dissolve at all. The increased solubility of the compounds was judged by the presence of well-structured absorption and emission spectra (see “Results and discussion”) whereas the 3,9-disubstituted perylenes did not yield any noticeable absorption spectrum [21] in polar solvents. All samples were prepared and handled under dim light conditions by dissolving the solid perylene analogues into a known volume of each solvent of interest to form a stock solution which was left equilibrating for 30 min.…”