Precision Begins with Materials: Inside the Science of Endoscopic Injection Needles

Precision Begins with Materials: Inside the Science of Endoscopic Injection Needles

Disposable endoscopic injection needles are widely used in endoscopic procedures such as submucosal lifting, sclerotherapy, hemostatic agent injection, and tattooing. Their design and material performance are critical for clinical safety and effectiveness.

A typical disposable injection needle consists of:

· Needle Tip: Made of medical-grade stainless steel, often beveled (e.g., 30°) to facilitate smooth tissue penetration with minimal trauma.

· Inner Tube: Connects the handle to the needle tip and delivers the injection solution. It is typically transparent for visual confirmation of blood or fluid flow.

· Outer Sheath: Covers the inner tube to provide structural support and reduce friction when passing through the endoscope’s working channel.

· Handle: Ergonomically designed for one-handed use; includes both a plunger mechanism for injection and a slider for advancing/retracting the needle.

· Luer Lock Connector: Attaches securely to syringes for precise fluid delivery.

Inner Tube

² Material: Typically stainless steel or reinforced medical polymers with excellent biocompatibility and chemical resistance.

² Transparency: A clear lumen allows operators to monitor for blood reflux and ensure accurate needle placement.

² Wall Thickness and Inner Diameter: Balanced to maintain structural integrity while enabling smooth fluid delivery.

² Smoothness: Inner surface must be polished to reduce friction and ensure consistent injection flow.

Outer Sheath

² Material: Often made of PTFE (Teflon) or other low-friction polymers that allow smooth passage through the scope.

² Flexibility and Strength: Must be flexible enough to bend through the scope while rigid enough to prevent buckling or collapse.

² Tight Seal with Inner Tube: Ensures no leakage and allows precise control of the needle’s movement.

² Surface Finish: A smooth external surface minimizes resistance and reduces the risk of damage to the endoscope channel.

The most common materials used for the tubing are PTFE (Polytetrafluoroethylene) and PP (Polypropylene). Each offers distinct advantages. So, how should healthcare providers choose between them?

This article provides a direct comparison to help make informed decisions.

Application Suggestions

· Choose PTFE When:

o You need chemical purity and high bio-compatibility;

o Smooth insertion and precision control are essential;

o Targeting premium/high-end medical devices;

o User feedback emphasizes tactile precision and feel.

· Choose PP When:

o You need large-volume, budget-sensitive supply;

o Basic clinical applications with routine use;

o Flexibility in usage with acceptable performance;

o Cost control is a priority without sacrificing safety.

Eco Polymer: Full PTFE & PP Lineup

As one of the few manufacturers with in-house PTFE extrusion capability, Eco Polymer offers:

· ✅ Reliable supply of both PTFE and PP tube

· ✅ Customizable specifications for different clinical needs

· ✅ Competitive pricing with premium performance

There is no one-size-fits-all material—only the right fit for the right purpose.
PTFE ensures superior safety and precision, while PP meets the need for economy and volume. At Eco, we understand both clinical demands and procurement realities. That’s why we offer dual-material solutions to help clients optimize performance and control costs.

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