Sterile Packaging: Silicone Septums for Multi-Dose Pharmaceutical Vials.
Sterile Packaging: Silicone Septums for Multi-Dose Pharmaceutical Vials.
A
RubberQ Engineering

Sterile Packaging: Silicone Septums for Multi-Dose Pharmaceutical Vials
Problem Statement
Multi-dose pharmaceutical vials require septums that maintain sterility after 100+ needle penetrations while resisting drug interaction and autoclaving (121°C, 15 psi). Standard silicone compounds fail due to:
- High compression set (>30%) causing seal failure after repeated punctures
- Extractable silicone oils contaminating biologics
- Swelling in polar solvents (e.g., DMSO, ethanol-based solutions)
Material Science Analysis
RubberQ's platinum-cured LSR (Liquid Silicone Rubber) outperforms peroxide-cured silicones and bromobutyl rubber due to:
- Crosslink density: Platinum catalysis creates tighter networks with 40% lower extractables vs. peroxide systems
- Filler selection: High-purity silica (<50 ppm heavy metals) prevents drug adsorption
- Additive package: Non-migrating antistatic agents reduce particle shedding during needle insertion
Technical Specifications
- Shore A Hardness: 50 ±5 (ISO 868)
- Tensile Strength: 8.5 MPa (ASTM D412)
- Elongation at Break: 450% (ASTM D412)
- Compression Set (22 hrs @ 100°C): ≤15% (ASTM D395 Method B)
- Temperature Range: -60°C to 200°C (intermittent)
- ISO 10993-5 Cytotoxicity: Class VI compliant
| Parameter | Platinum LSR (RubberQ) | Peroxide-Cured HTV Silicone | Bromobutyl Rubber |
|---|---|---|---|
| Needle Penetration Force (21G, 100 cycles) | 1.8 ±0.2 N | 2.5 ±0.4 N | 3.1 ±0.5 N |
| Extractables (USP <661>) | ≤0.5% | ≤1.2% | ≤2.8% |
| Swelling in 70% Ethanol (24 hrs) | +3% volume | +8% volume | +15% volume |
| Autoclave Cycles Before Failure | ≥50 | 30 | 10 |
Standard Compliance
RubberQ's IATF 16949-certified production ensures:
- Batch traceability of raw materials (ASTM D2000 lineage tracking)
- Statistical process control (SPC) on durometer (±2 Shore A tolerance)
- ISO 3601-1 leak testing on 100% of production units
For custom material compound development or IATF 16949 documentation, consult RubberQ's engineering department.
Subscribe to Technical Updates
Receive new material insights and engineering case notes directly by email.