Preparation, Characterization, and Antioxidant Capacity of Xanthone-Urea Complex

Area of Science:

• Pharmaceutical Sciences
• Materials Science

Background:

• Xanthones possess broad therapeutic properties, including antitumor and anti-inflammatory effects.
• Poor solubility limits the therapeutic application of many xanthone compounds.
• Complexation is a strategy to improve the physicochemical properties of poorly soluble drugs.

Purpose of the Study:

• To enhance the solubility and dissolution of a poorly soluble xanthone.
• To prepare a 1:1 molar ratio xanthone-urea complex using cogrinding.
• To characterize the complex and evaluate its improved properties.

Main Methods:

• Cogring method using a vibration rod mill to prepare the xanthone-urea complex.
• Differential Scanning Calorimetry (DSC) for thermal analysis.
• Powder X-ray Diffraction (PXRD) and Scanning Electron Microscopy (SEM) for structural characterization.
• Fourier Transform Infrared (FTIR) spectroscopy and Diffusion Ordered Spectroscopy Nuclear Magnetic Resonance (DOSY-NMR) for molecular interaction analysis.
• Solubility, dissolution, and antioxidant capacity assessments.

Main Results:

• Coginding resulted in a 1:1 molar ratio xanthone-urea complex with altered thermal, structural, and morphological properties.
• Significant improvements in solubility (nearly 2-fold increase) and dissolution rates were observed for the complex.
• The xanthone-urea complex demonstrated enhanced antioxidant capacity compared to native xanthone.
• Spectroscopic and NMR analyses confirmed successful complexation and altered molecular diffusion.

Conclusions:

• The cogrinding method effectively produced a 1:1 xanthone-urea complex with significantly enhanced solubility and dissolution.
• The developed complex exhibits improved physicochemical properties and augmented antioxidant activity.
• This formulation strategy holds promise for improving the therapeutic efficacy of poorly soluble xanthones.