Interaction of doxorubicin with phospholipid monolayers

Area of Science:

• Biochemistry
• Surface Chemistry
• Molecular Interactions

Background:

• Doxorubicin hydrochloride is a widely used chemotherapy drug.
• Understanding drug-lipid interactions is crucial for drug delivery and efficacy.
• Anthracenesulfonate derivatives share structural similarities with known DNA-intercalating agents.

Purpose of the Study:

• To quantify the interaction energies between doxorubicin hydrochloride and sodium 1,2,4-trihydroxy-9,10-dioxo-3-anthracenesulfonate with specific phospholipid monolayers.
• To elucidate the nature of intermolecular forces governing these interactions.
• To compare these forces with those observed in drug-DNA interactions.

Main Methods:

• Formation of dipalmitoylphosphatidylethanolamine (DPPE) and dipalmitoyllecithin (DPL) monolayers at the air-water interface.
• Subphase injection of doxorubicin hydrochloride and sodium 1,2,4-trihydroxy-9,10-dioxo-3-anthracenesulfonate.
• Measurement of surface pressure changes to determine interaction energies.

Main Results:

• The interaction energies were estimated based on the increase in surface pressure with increasing compound concentrations.
• Calculated interaction energies were in the range of those previously reported for doxorubicin and acridines with double-stranded DNA.
• These results indicate a significant interaction between the tested compounds and the lipid monolayers.

Conclusions:

• The observed interaction energies suggest that van der Waals forces play a significant role in the interaction of doxorubicin hydrochloride and the anthracene derivative with phospholipid monolayers.
• The findings imply that similar intermolecular forces, specifically van der Waals forces, are operative in both drug-lipid and drug-DNA interactions.
• This provides insights into the biophysical mechanisms underlying drug interactions with biological membranes and genetic material.