Syringe Needle Testing
There are multiple testing standards outlining methods for evaluating straight stainless steel needles used in healthcare applications. These standards are used by injection device manufacturers and the pharmaceutical companies that use them for drug delivery. Testing standards for syringe needles are necessary in order to regulate the products that reach the healthcare frontlines. They are critical for ensuring that sharps injuries are prevented and that injection doses can be delivered successfully. Failure can result in injury to the patient or the healthcare professional administering the drug. Failure can also cause an incorrect dosage to be administered to the patient, which leads to additional adverse effects. There are a number of testing standards that follow the raw material through the entire product development process:
ISO 9626
ISO 9626 is typically the first standard referenced, as it defines the mechanical properties requires for stainless steel tubing intended to be manufactured into needles. This standard includes methods to assess the strength and durability of the steel tubing to ensure it meets the requirements necessary for the end product. The required forces are dependent on the needle gauge and wall thickness, two factors that will dictate which application the needle will be used for.
Testing is performed using a 3-point bending assembly to determine the stiffness of the material. Additionally, a cantilever bend test is performed to assess the tubing's ability to withstand breakage. This test is critical to ensure the needle can withstand the shearing forces it may encounter in clinical environments.
ISO 7864
The substrate choice for penetration is critical in gathering valid data from the test, and ensuring the substrate layer is taught prior to testing is also very important for getting repeatable results. The standard explicitly outlines the options available for testing.
ASTM F3014
ISO 11040
This evaluation mainly focuses on the functionality of the device, quantifying the torques required to assemble and disassemble the needle hub from injection device. As with the other standards discussed, the bond strength between the needle and hub must also be determined.
Materials Testing System
Syringe needle testing should be performed on a low force universal testing system such as Instron's 68SC-1 with Bluehill Universal software. Penetration forces are less than 10 N but for all other tests 100 N capacity is appropriate. ISO 11608-2 testing requires Torsion Add-On 3.0. For ISO 9626, custom test fixtures are required (bend fixture and cantilever bend fixture). When testing the needle hub bond strength, proper alignment is required between the hub and the needle. Any angular or concentric misalignment can cause additional force to be required for the needle removal.
| ISO 11040 Test Setup | |
|---|---|
| 1) | 6800 Series Universal Testing System |
| 2) | Bluehill Universal Software |
| 3) | 2527 Series Load Cell |
| 4) | Torsion Add-On 3.0 |
| 5) | CP132121 Modular Test Fixture |
6800 Series Premier Testing Systems Brochure
Instron 6800 Series Universal Testing Systems provide unparalleled accuracy and reliability. Built on a patent-pending Operator Protect system architecture with an all-new Smart-Close Air Kit and Collision Mitigation features, the 6800 Series makes materials testing simpler, smarter, and safer than ever before.
Bluehill Universal Brochure
Bluehill Universal is Instron’s advanced materials testing software, designed for intuitive touch interaction and streamlined workflows. It offers pre-loaded test methods, QuickTest for rapid setup, enhanced data exporting, and Instron Connect for direct service communication. Users of Bluehill 2 and Bluehill 3 can easily upgrade to the latest version for improved performance and usability
Torsion Add On 3.0 for Electromechanical Testing Systems Data Sheet
The Torsion Add-On 3.0 for electromechanical universal testing systems is designed for simple, simultaneous axial and torsional testing of devices and/or components. Torsion Add-On 3.0 easily mounts to any new or existing Instron 6800 or 5900 system, adding torsion capability to your lab while saving valuable lab space. It utilizes Bluehill Universal’s dedicated axial-torsion and method types in a user-friendly and intuitive interface.
ISO 11040 4 Fixtures for Testing Prefilled Glass Syringes
Pre-filled glass syringes are most commonly tested to ISO 11040-4. As glass syringes are more susceptible to failure than plastic syringes, a wider variety of tests are required to be performed on them. Within ISO 11040-4 there are a total of 10 annexes, each requiring a different mechanical test. All fixtures are compatible with the Torsion Add-On for 5900 systems, as some of the annexes require simple rotation.
Curved Needle Testing Systems
The Instron® Needle Testing System is ideally suited for needles used in abdominal, fistula, vascular, intestinal, or other surgical procedures. This system provides two different needle testing solutions: one for curved needle puncture testing and one for bend testing. The curved needle puncture testing fixture is used to evaluate needle sharpness and insertion force, while the needle bend testing fixture is used to evaluate flexural properties of the needle during use. With its tabletop design, the Curved Needle Testing System has a small footprint and takes up minimal benchtop space. The testing system operates with Instron Bluehill® 3 Software that provides test control, data acquisition,test results, and reports, as well as a large library of calculations.
