Coning phenomena under laminar flow

Mizuki Higuchi; Katsuhide Terada; Kiyohiko Sugano

doi:10.1016/j.ejps.2015.08.004

Coning phenomena under laminar flow

Eur J Pharm Sci. 2015 Dec 1:80:53-5. doi: 10.1016/j.ejps.2015.08.004. Epub 2015 Aug 19.

Authors

Mizuki Higuchi¹, Katsuhide Terada¹, Kiyohiko Sugano²

Affiliations

¹ Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan.
² Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan. Electronic address: kiyohiko.sugano@phar.toho-u.ac.jp.

PMID: 26296866
DOI: 10.1016/j.ejps.2015.08.004

Abstract

The purpose of the present study was to investigate coning phenomena in the paddle dissolution test under laminar flow (Reynolds number <500). The minimum rotation speed at which the coning phenomena disappear (no coning rpm, NCrpm) was measured in viscous media (23 to 147mPa∙s) using various particles. The exponent values of particle size, density, and viscosity parameters in the Zwietering equation were found to be 0.066, 0.38, and 0.22, respectively. NCrpm was appropriately predicted by the Zwietering equation (average error: 8rpm). These values are very different from those for turbulent flow, suggesting that the main physical forces governing the motion of particles can be different between turbulent flow and laminar flow. This point should be taken into account when understanding the dissolution of drug products in viscous fluids representing the fed state.

Keywords: Coning; Laminar flow; Paddle; Particle shape; Zwietering equation.

MeSH terms

Nuclear Proteins
Pharmacokinetics*
RNA-Binding Proteins
Rheology*
Rotation
Technology, Pharmaceutical / methods*

Substances

MCRS1 protein, human
Nuclear Proteins
RNA-Binding Proteins