If you are experiencing problems downloading PDF or HTML fulltext, our helpdesk recommend clearing your browser cache and trying again. If you need help in clearing your cache, please click here . Still need help? Email help@ingentaconnect.com

Open Access A comparison of capillary and rotational viscometry of aqueous solutions of hypromellose

 Download
(PDF 66.2kb)
 
Download Article:

Abstract:

A comparison of capillary and rotational viscometry of gentle pseudoplastic solutions of hypromellose (HPMC 4000) by using only single-point value of viscosity is difficult. Single-point comparison becomes topical in consequence to the pharmacopoeial requirement that the apparent viscosity of 2% hypromellose solution should be read at the shear rate of approximately 10 s–1. This communication is focused on the estimation of the suitable shear rate, Dη, at which the apparent viscosity read using the rotational viscometer is numerically equal to the dynamic viscosity read using a capillary viscometer. For the solutions of HPMC in concentrations up to 2% w/v, the non-linear regression equations generated showed the influencing of the Dη value by the dynamic viscosity and/or by the originally derived linear velocity of the solution flowing through the capillary viscometer tube. To compare the apparent viscosity read using the rotational viscometer with the dynamic viscosity read using capillary viscometer, the exact estimation of the shear rate Dη at which both viscosities are numerically equal is essential since it is markedly affected by the concentration of HPMC solution.

Document Type: Research Article

DOI: http://dx.doi.org/10.1691/ph.2007.10.7076

Affiliations: 1: Department of Pharmaceutical Technology, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Heyrovského 1203, Hradec Králové, 500 05, Czech Republic, Email: zdenka.sklubalova@faf.cuni.cz 2: Department of Pharmaceutical Technology, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Hradec Králové, Czech Republic

Publication date: October 1, 2007

More about this publication?
  • Pharmazie is one of the world's leading pharmaceutical journals. As a peer-reviewed scientific journal, DiePharmazie is regularly indexed in Current Contents/Life Sciences, Excerpta Medica, Analytical Abstracts, International Pharmaceutical Abstracts, Beilstein Current Facts in Chemistry, Chemical Engineering and Biotechnology Abstracts (CEABA) and Science Citation Index.
  • Information for Authors
  • Submit a Paper
  • Subscribe to this Title
  • Terms & Conditions
  • ingentaconnect is not responsible for the content or availability of external websites
Related content

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more