Physicochemical characterization and cytotoxic activity evaluation of hydroxymethylferrocene:β-cyclodextrin inclusion...

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Pharmacology

Background:

• Hydroxymethylferrocene (FeMeOH) is a ferrocene derivative with potential applications.
• Beta-cyclodextrin (β-CD) is a cyclic oligosaccharide known for its ability to form inclusion complexes.
• Complexation can modify the physicochemical and biological properties of guest molecules.

Purpose of the Study:

• To prepare and characterize solid-state inclusion complexes of FeMeOH with β-CD.
• To investigate the stoichiometry, stability, and solubility of the FeMeOH-β-CD complex.
• To evaluate the cytotoxic activity of the inclusion complex compared to free FeMeOH.

Main Methods:

• Solid-state preparation techniques: physical mixture, coprecipitation, kneading, freeze-drying.
• Characterization: X-ray Powder Diffractometry (XRPD), Fourier Transform-Infrared spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR).
• Solution studies: Job plot for stoichiometry, UV-Vis titration and phase solubility for stability constants (Kb) and solubility.

Main Results:

• Successful formation of FeMeOH-β-CD inclusion complexes confirmed by XRPD and FTIR.
• 1:1 stoichiometry established in aqueous solution.
• Stability constants (Kb) determined by NMR (478 M⁻¹) and UV-Vis (541.3 M⁻¹), consistent with phase solubility estimations (528.0 M⁻¹).
• Slight increase in FeMeOH solubility observed in the presence of β-CD (Bs type phase solubility diagram).
• MTT assay showed the inclusion complex exhibited higher cytotoxic activity against MDA-MB-231 cells than FeMeOH alone.

Conclusions:

• Solid-state inclusion complexes of FeMeOH with β-CD can be effectively prepared.
• The complexation enhances the cytotoxic efficacy of FeMeOH, suggesting potential therapeutic advantages.
• This study highlights the utility of β-CD as a carrier to improve the properties of FeMeOH.