Indomethacin: Effect of Diffusionless Crystal Growth on Thermal Stability during Long-Term Storage

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216275%3A25310%2F23%3A39920250" target="_blank" >RIV/00216275:25310/23:39920250 - isvavai.cz</a>

Result on the web

<a href="https://www.mdpi.com/1420-3049/28/4/1568" target="_blank" >https://www.mdpi.com/1420-3049/28/4/1568</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/molecules28041568" target="_blank" >10.3390/molecules28041568</a>

Result language

angličtina

Original language name

Indomethacin: Effect of Diffusionless Crystal Growth on Thermal Stability during Long-Term Storage

Original language description

Differential scanning calorimetry and Raman spectroscopy were used to study the non-isothermal and isothermal crystallization behavior of amorphous indomethacin powders (with particle sizes ranging from 50 to 1000 mu m) and their dependence on long-term storage conditions, either 0-100 days stored freely at laboratory ambient temperatures and humidity or placed in a desiccator at 10 degrees C. Whereas the gamma-form polymorph always dominated, the accelerated formation of the alpha-form was observed in situations of heightened mobility (higher temperature and heating rate), increased amounts of mechanically induced defects, and prolonged free-surface nucleation. A complex crystallization behavior with two separated crystal growth modes (originating from either the mechanical defects or the free surface) was identified both isothermally and nonisothermally. The diffusionless glass-crystal (GC) crystal growth was found to proceed during the long-term storage at 10 degrees C and zero humidity, at the rate of similar to 100 mu m of the gamma-form surface crystalline layer being formed in 100 days. Storage at the laboratory temperature (still below the glass transition temperature) and humidity led only to a negligible/nondetectable GC growth for the fine indomethacin powders (particle size below similar to 150 mu m), indicating a marked suppression of GC growth by the high density of mechanical defects under these conditions. The freely stored bulk material with no mechanical damage and a smooth surface exhibited zero traces of GC growth (as confirmed by microscopy) after &gt;150 days of storage. The accuracy of the kinetic predictions of the indomethacin crystallization behavior was rather poor due to the combined influences of the mechanical defects, competing nucleation, and crystal growth processes of the two polymorphic phases as well as the GC growth complex dependence on the storage conditions within the vicinity of the glass transition temperature. Performing paired isothermal and nonisothermal kinetic measurements is thus highly recommended in macroscopic crystallization studies of drugs with similarly complicated crystal growth behaviors.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10403 - Physical chemistry

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Molecules

ISSN

1420-3049

e-ISSN

1420-3049

Volume of the periodical

28

Issue of the periodical within the volume

4

Country of publishing house

CH - SWITZERLAND

Number of pages

22

Pages from-to

"1568-1"-"1568-22"

UT code for WoS article

000940953600001

EID of the result in the Scopus database

2-s2.0-85149240723