Microwave continuous sterilization of injection ampoules

Area of Science:

• Pharmaceutical Technology
• Sterilization Methods
• Microwave Engineering

Background:

• Traditional autoclaving poses challenges for heat-sensitive pharmaceutical ingredients.
• Need for advanced sterilization techniques in ampoule production.
• Development of microwave dielectric heating as a potential alternative.

Purpose of the Study:

• To develop a microwave continuous sterilizer (MWS) for pharmaceutical ampoule sterilization.
• To achieve effective sterilization of heat-sensitive drugs while minimizing degradation.
• To ensure automated, continuous operation compatible with production lines.

Main Methods:

• Utilized microwave dielectric heating to rapidly heat drug solutions in ampoules to 140°C within 30 seconds.
• Implemented techniques to minimize temperature distribution, including counter-directional irradiation and targeted heating.
• Controlled microwave power and heating rate based on real-time temperature feedback and dielectric properties.
• Validated sterilization efficacy using Bacillus stearothermophilus spores and assessed drug stability.

Main Results:

• The MWS achieved target F0 values by maintaining 140°C for 12 seconds, followed by cooling.
• Sterilization was effective, with minimal chemical degradation observed in 3% pyridoxamine phosphate solution.
• The system processed 150 ampoules per minute, demonstrating high throughput.
• Optimized microwave irradiation and feedback control minimized temperature variations within ampoules.

Conclusions:

• The developed MWS provides an efficient and effective sterilization method for pharmaceutical ampoules, especially those with heat-sensitive ingredients.
• This technology offers a viable alternative to autoclaving, reducing chemical degradation and preserving drug integrity.
• The MWS integrates seamlessly into continuous production processes, enhancing manufacturing efficiency.