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Published on: February 7, 2017
Polymer templating of supercooled indomethacin for polymorph selection.
ACS Combinatorial Science
|February 16, 2012
Summary
This study introduces a simple method for polymorph screening of stable pharmaceutical compounds using polymer surfaces. This technique directs the crystallization of active pharmaceutical ingredients from a supercooled melt, enabling efficient parallel screening.
Area of Science:
- Materials Science
- Pharmaceutical Science
- Crystallography
Background:
- Pharmaceutical polymorph screening is crucial for drug development.
- Previous methods utilized polymer libraries for solution crystallization.
- Active pharmaceutical ingredients (APIs) can adopt different crystalline forms (polymorphs).
Discussion:
- This work presents a solvent-free polymorph screening technique using homopolymer surfaces.
- The method involves recrystallization from a supercooled melt of thermally stable pharmaceutical compounds.
- Homopolymer surfaces template the crystallization of APIs, directing polymorph selection.
Key Insights:
- Indomethacin, a nonsteroidal anti-inflammatory drug, preferentially crystallizes as the alpha (α) polymorph on specific polymer surfaces, deviating from its usual delta (δ) polymorph formation from a melt on untreated surfaces.
- This polymer templating effect occurs in the absence of a solvent, utilizing recrystallization from the supercooled melt.
- The technique is adaptable to multiwell plate formats, allowing for parallel screening with minimal sample amounts.
Outlook:
- This method offers a simplified approach to polymorph screening for thermally stable compounds.
- Potential for high-throughput screening and parallel experimentation in pharmaceutical research.
- Facilitates characterization via X-ray powder diffraction (XRPD).
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