Reducing crack occurrence from frictive damage with externally coated pharmaceutical glass vials

Area of Science:

• Pharmaceutical Packaging
• Materials Science
• Mechanical Engineering

Background:

• Parenteral glass packaging is susceptible to strength-limiting defects during handling, increasing risks of cracking and breakage.
• Vial cracking is a critical defect that can compromise drug sterility and patient safety.
• External low coefficient of friction coatings offer a potential solution to mitigate damage from frictive contact.

Purpose of the Study:

• To evaluate the effectiveness of external coatings in preventing cracking and breakage of Type I borosilicate glass vials.
• To quantify the impact of these coatings on vial strength under applied loads.
• To assess the shift in the onset load for cracking in coated versus uncoated vials.

Main Methods:

• Utilized a ball-on-heel test to simulate blunt frictive contact stresses on glass vials.
• Tested both uncoated and externally coated Type I borosilicate glass vials.
• Applied loads ranging from 50 N to 350 N to observe vial responses.

Main Results:

• The external coating demonstrated a significant reduction in cracking probability, approximately threefold compared to uncoated vials (95% confidence).
• Coated vials exhibited a higher load threshold for cracking, shifting from 200 N for uncoated vials to 250 N for coated vials.
• Observed vial responses included survival, cracking, and breakage, with coatings improving overall resilience.

Conclusions:

• External low coefficient of friction coatings effectively enhance the mechanical resistance of Type I borosilicate glass vials.
• These coatings provide a substantial safety improvement by reducing the likelihood of critical defects like cracking.
• The application of such coatings is a promising strategy for improving the integrity and safety of parenteral glass packaging.