Modified Biochanin A Release from Dual pH- and Thermo-Responsive Copolymer Hydrogels

Area of Science:

• Polymer Chemistry
• Drug Delivery Systems
• Biomaterials Science

Background:

• Biochanin A, a methoxylated isoflavone, possesses significant estrogenic and pharmacological activities.
• Poor aqueous solubility and extensive first-pass metabolism limit biochanin A's bioavailability.
• Developing effective delivery systems is crucial for enhancing biochanin A's therapeutic potential.

Purpose of the Study:

• Synthesize a temperature- and pH-responsive poly(N-isopropylacrylamide-co-acrylic acid) [p(NIPAM-co-AA)] copolymer.
• Investigate the copolymer as a carrier for modified release of biochanin A.
• Evaluate biochanin A release under physiological conditions relevant to vaginal and rectal administration.

Main Methods:

• Free radical polymerization for copolymer synthesis.
• Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) for structural characterization.
• Ultra-visible spectroscopy (UV-Vis) for quantifying released biochanin A.
• High-performance liquid chromatography (HPLC) for residual monomer analysis.
• Factorial design for modeling copolymer swelling behavior in response to temperature and pH.

Main Results:

• The p(NIPAM-co-AA) copolymer was successfully synthesized and characterized.
• The copolymer demonstrated temperature- and pH-dependent swelling behavior.
• Incorporation and subsequent release of biochanin A from the copolymer were confirmed.
• The release profile was studied at body temperature and relevant physiological pH values.

Conclusions:

• The synthesized p(NIPAM-co-AA) copolymer is a promising carrier for the modified release of biochanin A.
• The responsive nature of the copolymer allows for controlled drug release under specific physiological conditions.
• This approach holds potential for improving the bioavailability and therapeutic efficacy of biochanin A.