Formulation Effects on the Thermomechanical Properties and Permeability of Free Films and Coating Films: Characterization of Cellulose Acetate Films - Pharmaceutical Technology

Latest Issue
PharmTech

Latest Issue
PharmTech Europe

Formulation Effects on the Thermomechanical Properties and Permeability of Free Films and Coating Films: Characterization of Cellulose Acetate Films
The authors investigate the effects of a polyethylene glycol plasticizer and water on cellulose acetate film properties.


Pharmaceutical Technology
Volume 33, Issue 3, pp. 88-100

Cellulose acetate (CA) is a polymeric excipient widely used in pharmaceutical dosage forms for controlled release (1–5) and taste masking (6–8). CA also is one of the most suitable materials to serve as a semipermeable membrane for osmotic drug delivery systems (9–10).

Although osmotic drug delivery systems have many designs and configurations, they generally consist of a tablet core surrounded by a semipermeable membrane (11). When designing an osmotic drug delivery system, many factors could affect the release rate of an active needed to be delivered. Selection and design of the semipermeable membrane remain one of great challenges for formulation scientists.

Knowing the relationship between a formulation and its film properties is crucial for designing a membrane to control release rate. Yuan et al. have investigated the effects of solvent systems (acetone and acetone/water), polyethylene glycol (PEG) molecular weight and level on the properties of CA-free films (12). In that study, water as a cosolvent in the formulation definitely affected morphology, and ultimately, the properties of the films. The films prepared from acetone were transparent, flexible, stronger, but less permeable to water vapor compared with those films containing water as a cosolvent. Meier et al. published similar results when they studied the influence of the plasticizer content and film preparation procedure on the morphology, thermal, and mechanical properties of CA films plasticized with poly(caprolactone triol) (PCL-T) (13). They demonstrated that the addition of water, a nonsolvent, during the membrane-casting process was a simple and effective way to change membrane porosity and consequently the drug-permeation profile. When small quantities of nonsolvent were used to obtain low-porosity membranes, the presence of a plasticizer agent could be used to better modulate drug permeation (14).

In general, as the acetyl content in CA increases, the CA film permeability decreases, solvent resistance increases, and the glass transition temperature increases (15). However, for the small variation within the specification of CA-398-10NF-EP, no study has been found to address the effect of the acetyl content on CA film properties. Although free film properties would provide insights for predicting permeability of the films, applying CA polymer onto a substrate is a final step to ensure the release profile as designed. The objectives of this study were to investigate the acetyl content in CA polymer on the film properties, particularly the permeability of free films and coating films, and to study the effects of plasticizer level (polyethylene glycol 3350) and water level on the properties of free films and coating films.


ADVERTISEMENT

blog comments powered by Disqus
LCGC E-mail Newsletters

Subscribe: Click to learn more about the newsletter
| Weekly
| Monthly
|Monthly
| Weekly

Survey
FDASIA was signed into law two years ago. Where has the most progress been made in implementation?
Reducing drug shortages
Breakthrough designations
Protecting the supply chain
Expedited reviews of drug submissions
More stakeholder involvement
Reducing drug shortages
70%
Breakthrough designations
4%
Protecting the supply chain
17%
Expedited reviews of drug submissions
2%
More stakeholder involvement
7%
View Results
Eric Langerr Outsourcing Outlook Eric LangerTargeting Different Off-Shore Destinations
Cynthia Challener, PhD Ingredients Insider Cynthia ChallenerAsymmetric Synthesis Continues to Advance
Jill Wechsler Regulatory Watch Jill Wechsler Data Integrity Key to GMP Compliance
Sean Milmo European Regulatory WatchSean MilmoExtending the Scope of Pharmacovigilance Comes at a Price
From Generics to Supergenerics
CMOs and the Track-and-Trace Race: Are You Engaged Yet?
Ebola Outbreak Raises Ethical Issues
Better Comms Means a Fitter Future for Pharma, Part 2: Realizing the Benefits of Unified Communications
Better Comms Means a Fitter Future for Pharma, Part 1: Challenges and Changes
Source: Pharmaceutical Technology,
Click here