Blog › Quality Series › Chapter 4
◆ Quality Series · Part 4
In short: quality starts before production — with the povidone-iodine, the degreased cotton, the plastic stick and the pouch film, and the suppliers behind them.
The materials that decide the swab
| Material | Specification | Control |
|---|---|---|
| Povidone-iodine (active) | Pharmaceutical-grade; compounded to 4.5–5.5 g/L available iodine | Incoming available iodine & pH |
| Degreased cotton head | Medical-grade absorbent cotton | Appearance, absorbency |
| Plastic stick | Hardness and diameter to spec | Hardness, dimensions, head adhesion |
| Pouch film | Light-proof barrier laminate | Seal and iodine-barrier performance |
Heavy metals — controlled at the source
Because povidone-iodine is the active, its purity flows straight into the finished product. We hold the solution to lead ≤ 10, arsenic ≤ 2 and mercury ≤ 1 mg/kg, and control these at incoming so they never reach the line.
Why we screen for optical brighteners
Many commodity cottons contain fluorescent whitening agents to look brighter. Under UV light these show a strong blue fluorescence. For a skin-contact product we screen incoming cotton and reject strong blue fluorescence — only the faint natural fluorescence of clean fibre is acceptable.
Supplier qualification
- Quality agreements with key suppliers (povidone-iodine, cotton, plastic stick).
- A quality file and periodic evaluation for each key supplier.
- Incoming inspection on every lot before material is released to production.
For buyers — what to ask for: the material specifications and grades (cotton standard, povidone-iodine grade, stick hardness), the heavy-metal limits, and whether the cotton is screened for optical brighteners.
