Aqueous-Based Cellulose Acetate Butyrate Dispersion: Screening of Process and Formulation Variables to Obtain Verapamil HCl-Controlled Release Beads Academic Article uri icon


  • The objectives of the present investigation were to evaluate the possibility of using a custom-designed cellulose acetate butyrate (CAB) pseudolatex dispersion on Verapamil HCl-loaded beads for sustained release of the drug. Excipient compatibility was studied by thermal analysis, X-ray diffraction, and content analysis. Inert beads (Nupareil) were loaded with verapamil HCl and subsequently coated with CAB pseudolatex dispersion. Process and formulation factors were screened by Plackett-Burman screening design in order to identify the most important factors affecting the amount of verapamil HCl released in 12 hours. X-ray diffraction pattern and content analysis showed no degradation of verapamil HCl and suggested absence of any interaction. However, thermal analysis indicated an interaction between verapamil HCl and excipient. A polynomial equation was developed to show the relationship between dependent and independent variables. The mathematical model fitted the data and explained 98.05% of variability in the response. The difference between observed and predicated values of any given run did not exceed 6% of maximum cumulative release at 12 hours. Plackett-Burman screening design identified coating weight gain, duration of curing, and amount of plasticizer as the most important factors determining cumulative percent released in 12 hours. Amount of Polydextrose/HPMC (Opadry II), spray rate, fluid bed coater outlet temperature, and atomizing pressure had no statistically significant (p < 0.05) influence on the response.

published proceedings

  • Particulate Science And Technology

author list (cited authors)

  • Vaithiyalingam, S., Reddy, I. K., Khan, M. A., & Guven, N.

citation count

  • 5

complete list of authors

  • Vaithiyalingam, Siva||Reddy, Indra K||Khan, Mansoor A||Guven, Necip

publication date

  • April 2001