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Monitoring the baicalein-betaine cocrystal process by terahertz spectroscopy
Shuo Zhao1, Lei Wang2, Chengqian You3
1School of Electrical and Information Engineering, Zhengzhou University, Zhengzhou 450001, PR China.
Summary
Terahertz (THz) spectroscopy effectively monitors the cocrystallization of baicalein (BAI) and betaine (BTN). This technique tracks molecular interactions, optimizing traditional Chinese medicine (TCM) active pharmaceutical ingredients (APIs) for better efficacy.
Area of Science:
- Pharmaceutical Science
- Materials Science
- Spectroscopy
Background:
- Cocrystallization enhances physicochemical properties of active pharmaceutical ingredients (APIs), especially those from traditional Chinese medicine (TCM).
- Investigating cocrystallization processes is crucial for optimizing API properties like solubility and bioavailability.
- Terahertz (THz) spectroscopy is well-suited for studying intermolecular interactions driving cocrystallization.
Purpose of the Study:
- To achieve and characterize the cocrystallization of baicalein (BAI) and betaine (BTN) using THz spectroscopy.
- To monitor the real-time progress of cocrystal formation.
- To elucidate the molecular configurations and interaction mechanisms within BAI-BTN cocrystals.
Main Methods:
- Cocrystallization achieved via liquid-assisted grinding.
- Characterization using terahertz time-domain spectroscopy (THz-TDS).
- Analysis of spectral evolution and fitting with the Johnson-Mehl-Avrami-Kolmogorov (JMAK) model.
- Density functional theory (DFT) simulations for spectral calculation.
Main Results:
- THz spectra showed distinct peaks for BAI, BTN, and their cocrystal, enabling real-time monitoring.
- Peak intensity changes at 1.53 THz (substrate) and 1.27 THz (cocrystal) tracked reaction progress.
- JMAK model analysis indicated a 3D nucleation-and-growth process with an Avrami exponent of 3.
- DFT simulations provided insights into molecular configurations and interactions.
Conclusions:
- THz spectroscopy is a feasible and powerful tool for monitoring cocrystallization processes.
- The study provides key reference data for understanding BAI-BTN cocrystal formation.
- This approach can aid in optimizing TCM-derived APIs for enhanced therapeutic efficacy.
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