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Diffuse Reflectance Infrared Spectroscopic Identification of Dispersant/Particle Bonding Mechanisms in Functional Inks

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Published on: May 8, 2015

Biphasic drug release testing coupled with diffusing wave spectroscopy for mechanistic understanding of solid

Sandra Jankovic¹, Patrick J O'Dwyer², Karl J Box³

¹University of Applied Sciences Northwest Switzerland, Institute of Pharma Technology, Gründenstrasse 40, Basel, Switzerland; University of Basel, Department of Pharmaceutical Sciences, Basel, Switzerland.

European Journal of Pharmaceutical Sciences : Official Journal of the European Federation for Pharmaceutical Sciences

|July 14, 2019

Summary

Amorphous solid dispersions (ASDs) enhance drug absorption by preventing crystallization. Diffusing wave spectroscopy (DWS) revealed polymer effects on drug release from ASDs, offering a new tool for biopharmaceutical research.

Keywords:

Amorphous drug Biphasic dissolution test Colloids Diffusing wave spectroscopy Drug precipitation Microrheology Solid dispersion

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Published on: May 8, 2015

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Published on: August 22, 2018

Area of Science:

Pharmaceutical Sciences
Biophysics
Materials Science

Background:

Amorphous solid dispersions (ASDs) are crucial for improving the bioavailability of poorly water-soluble drugs.
Drug release from ASDs is complex, involving supersaturation, colloidal structures, and potential precipitation.
Understanding drug release mechanisms is vital for optimizing oral drug delivery systems.

Purpose of the Study:

To mechanistically study ketoconazole release from ASDs using a biphasic in vitro test.
To introduce and evaluate diffusing wave spectroscopy (DWS) for biopharmaceutical testing of solid dispersions.
To investigate the impact of different HPMCAS grades on drug release and microrheology.

Main Methods:

Hot melt extrusion was used to produce amorphous solid dispersions (ASDs) of ketoconazole.
A biphasic in vitro test simulating intestinal drug uptake was employed.
Diffusing wave spectroscopy (DWS) was utilized to analyze microrheological properties and drug release.

Main Results:

Amorphous formulations successfully prevented ketoconazole crystallization in the intestinal medium.
Microrheological differences were observed between polymer grades and plasticizers in the aqueous phase.
These microrheological variations influenced ketoconazole release and subsequent uptake into the organic layer.

Conclusions:

Diffusing wave spectroscopy (DWS) is a promising non-invasive tool for understanding drug release from ASDs.
Polymer properties significantly impact drug release kinetics and microrheology in supersaturating systems.
This study highlights DWS's potential for advancing biopharmaceutical research on advanced drug delivery formulations.