A secure lock for integrated syringe closures

Prefilled syringes are used more and more in injection systems that treat chronic diseases, such as rheumatism. These systems must be easy to use and deliver the right dose to patients. With this in mind, Gerresheimer AG created the Gx TELC (Tamper Evident Luerlock Closure) – a closure system for prefillable glass syringes.
Adapter of Gerresheimer´s Gx TELC system
The adapter of Gerresheimer´s Gx TELC system is made from Apec® 1745 polycarbonate. (Photo: Gerresheimer Bünde GmbH)

The Gx TELC features a combination syringe cap and luer lock adapter system, which connects to a needle for drug delivery. When a user turns the cap to open the syringe, tabs spread and the cap cannot be closed again. This tamper-evident feature prevents misuse and counterfeit medicines.

When selecting a material for the adapter, Gerresheimer turned to Apec® 1745 high-heat polycarbonate. This grade brings a variety of benefits to this application, including:

  • High heat resistance
  • High impact strength to protect the adapter from damage
  • Sterilization using conventional methods such as gamma rays or ethylene oxide
  • Dimensional stability and accuracy at high temperatures, ensuring that the entire component does not warp after hot steam sterilization at 143°C
  • Biocompatibility according to ISO 10993-1 standard for the biological evaluation of medical devices

The Gx TELC system is produced by two-component injection molding as a hard-soft combination. First, the adapter is molded from copolycarbonate, then the cap is injection molded from a thermoplastic elastomer. This creates a strong bond without need for an adhesive, ensuring that there are no chemical reactions that could cause increased torque. With the closure and adapter as one component, OEMs benefit from a simplified, cost-effective manufacturing process, while the users only have to mount one connected part on the syringes.

We provided Gerresheimer with extensive support during the development of the complex component, including material recommendations, technical application advice and assistance with the design of the manufacturing process. The Gx TELC is just one example of how Covestro materials can help create healthcare products that make life easier and safer for patients around the world.

For more information, email us: plastics@covestro.com.

Apec® is a registered trademark of the Covestro group.

« Back to Overview