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Terahertz and Raman vibrational spectroscopy detection and structural analysis of acyclovir hydrate polymorphs
Qiuhui Zhao1, Jiale Zhang1, Yaqi Jing1
1Centre for THz Research, China Jiliang University, Hangzhou, 310018, China.
Summary
Researchers studied two hydrated forms of acyclovir (ACV) using spectroscopy and simulations. Differences in terahertz spectra were significant, while Raman spectra showed minor variations, highlighting the impact of hydrogen bonds on ACV crystal structure.
Area of Science:
- Solid-state chemistry
- Pharmaceutical sciences
- Spectroscopy
Background:
- Hydrated polymorphs exhibit unique physicochemical properties due to variations in intermolecular interactions.
- Acyclovir (ACV) is an antiviral medication requiring careful control of its solid-state forms.
Purpose of the Study:
- To prepare and characterize two hydrated forms of acyclovir (ACV).
- To investigate the vibrational properties and structural differences of ACV hydrates.
- To elucidate the role of intermolecular hydrogen bonds in ACV hydrate polymorphism.
Main Methods:
- Preparation of ACV hydrates under controlled conditions.
- Characterization using terahertz (THz) and Raman spectroscopy.
- Computational analysis including Gaussian software simulations and Crystal software DFT calculations.
Main Results:
- Significant differences were observed in the terahertz spectra of the two ACV hydrates.
- Minor differences were detected in Raman spectra, attributed to similar internal packing modes.
- Vibrational mode analysis revealed the substantial influence of intermolecular hydrogen bonds on ACV's molecular structure and vibrational behavior during crystallization.
Conclusions:
- The study provides a new perspective on acyclovir hydrate polymorphism.
- Identified distinct spectral signatures for different ACV hydrates.
- Offers theoretical support for drug development and quality control of acyclovir formulations.
Keywords:
AcyclovirDensity functional theoryHydrated polymorphsRaman spectroscopyTerahertz time-domain spectroscopyMore Related Videos
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