ASTM D7709, Water Vapor Transmission Rate for Pharmaceutical Bottles and Blisters
ASTM D7709 is the standard for measuring the Water Vapor Transmission Rate (WVTR) of pharmaceutical bottles and blisters. It is used to precisely determine the barrier performance of primary packaging to ensure the stability and shelf life of medicinal products.
Key Aspects of the Standard
Scope :
Specifically developed for sealed pharmaceutical containers, including high-barrier bottles, high-barrier blisters, and quasi-barrier blisters.
Gravimetric Method:
The test measures the rate of weight gain by a desiccant(drying agent) enclosed within the package as water vapor permeates through the material.
Test Methods:
- Method A: Used for bottles (results in mg/bottle-day).
- Method B: Used for formed barrier blisters (results in mg/cavity-day).
- Method C: Used for formed quasi-barrier blisters (a simplified method for materials with lower barrier properties).
Test Conditions:
Testing is typically conducted at 40 °C and 75% relative humidity (RH), aligning with ICH accelerated stability testing conditions.
Significance:
It provides high sensitivity and precision (often using linear regression for calculations), allowing for clear discrimination between different barrier levels. This data is frequently used to meet requirements for USP <671>.
Applications of ASTM D7709:
Pharmaceutical Packaging Evaluation:
Measuring the Water Vapor Transmission Rate (WVTR) for high-barrier and quasi-barrier bottles and blisters to protect moisture-sensitive solid oral drugs.
Regulatory Compliance:
Providing the precise, quantitative data required for FDA and other global regulatory submissions regarding drug packaging stability.
Stability Studies:
Aligning with ICH accelerated stability testing conditions (typically 40 °C / 75% RH) to predict product shelf life.
Comparative Analysis:
Differentiating between alternative packaging systems to find the most cost-effective or highest-performing barrier option.
Quality Control & R&D:
Validating the effectiveness of closure systems (like induction seals) and developing new packaging materials.
Basis for Mandatory Standards:
Serving as the technical foundation for Method 1, 2, and 3 in the mandatory USP <671> chapter for container performance.
ASTM D7709-Certified Instruments
Instruments which are conform to ASTM D7709:
- With GraviTest the determination of water vapour transmission rates of polymeric films and other sheet materials by gravimetric method becomes mere child’s play.
- The new Automatic Gravimetric WVTR Tester GINTRONIC GraviTest 6250 comes with a 0.01mg balance as a standard feature. The 0.01 mg balance makes WVTR measurements of low perm materials 2-3 times faster than the previous generation systems.
- The same instrument like GINTRONIC GraviTest 6300/6400, but with 10 sample places with 30cm2 / 28,3cm2. Conforms to ASTM E96, JIS L1099 A1+A2 and many others.
