19 mL Round-Bottom Test Tubes — PPC, Natural, 16 × 125 mm (214-2346-08N) | 125/Bag
These 19 mL polypropylene copolymer (PPC) round-bottom test tubes measure 16 × 125 mm and are packaged 125/Bag for evaluation batches, specialty workflows, or small standing-stock needs. PPC is a modified polypropylene resin that delivers greater optical clarity and improved low-temperature flexibility compared with standard homopolymer PP, making these tubes the preferred choice when visual inspection of tube contents is a routine part of the workflow. Supplied non-sterile, they suit a broad range of clinical, research, and bench chemistry applications.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 214-2346-08N |
| Capacity | 19 mL |
| Dimensions | 16 × 125 mm |
| Geometry | Round Bottom |
| Material | Polypropylene Copolymer (PPC) |
| Color | Natural |
| Sterility | Non-Sterile |
| Pack Size | 125/Bag |
| BPA / Phthalate / Latex | BPA-Free, Phthalate-Free, Latex-Free |
| Country of Origin | USA |
Applications
- Optical inspection workflows — meniscus reading, turbidity assessment, and color-change endpoint monitoring benefit directly from PPC's superior wall clarity versus homopolymer PP
- Titration and manual endpoint detection — the clearer tube wall allows direct visual confirmation of color transitions without transferring the sample
- Cold-temperature protocols — refrigerator and −20 °C rack storage where PPC's improved low-temperature flexibility reduces the brittleness risk associated with homopolymer PP
- Organic solvent reactions — bench chemistry involving acetonitrile, methanol, or similar co-solvents, where PPC retains the broad solvent compatibility of the PP family
- Water-bath incubation — compatible with water-bath use up to approximately 80 °C in standard 16 × 125 mm racks
- Centrifugation — suitable for clinical centrifuge protocols in 16 × 125 mm rotor formats
- Evaluation and small-batch specialty use — the 125/Bag format is ideal for labs trialing PPC before committing to larger volumes or maintaining a small parallel stock alongside PP or PS tube inventories
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Aqueous buffers and saline | Excellent |
| Dilute acids and bases | Excellent |
| Acetonitrile / methanol | Good — consistent with PP-family solvent compatibility |
| Ethanol (<70%) | Good — short-term contact |
| Chlorinated solvents (e.g., chloroform) | Not recommended |
| Aromatic solvents (e.g., toluene) | Not recommended |
| Autoclave sterilization | Compatible with PP-class thermal ratings; confirm protocol requirements |
Quality & Procurement
Made in USA, these Caplugs® Evergreen tubes are produced from FDA-compliant, BPA-free, phthalate-free, latex-free PPC resin under ISO 9001 quality management. The copolymer architecture is engineered for tighter dimensional tolerances and consistent wall clarity across the production run. LabSupplies.com is an authorized dealer of Caplugs® Evergreen consumables and ships from USA inventory, typically the same business day for stocking items; volume pricing is available for multi-bag and institutional orders.
Frequently Asked Questions
What is PPC, and why choose it over standard polypropylene (PP) tubes?
PPC (polypropylene copolymer) incorporates a co-monomer into the PP chain during polymerization, which disrupts the crystalline structure of homopolymer PP. The result is a resin that is more optically transparent, more flexible at low temperatures, and easier to process to tight dimensional tolerances — while retaining PP's broad compatibility with aqueous buffers, dilute acids and bases, and many organic solvents such as acetonitrile and methanol.
Are these test tubes sterile?
No — they are supplied non-sterile in 125/Bag packaging. For applications requiring a sterile vessel, additional processing such as gamma irradiation or autoclave treatment may be performed; consult your facility's validation protocols before use in sterility-critical workflows.
Will these tubes fit standard 16 × 125 mm tube racks and clinical centrifuge rotors?
Yes. At 16 mm outer diameter and 125 mm length, these tubes are dimensionally equivalent to the standard 16 × 125 mm format accepted by common tube racks and clinical centrifuge rotor positions designed for that size. Always confirm rotor and rack specifications before centrifuging.
Why is the pack size 125/Bag rather than the 1000/Bag available for PP and PS equivalents?
The 125/Bag format is designed as the evaluation and specialty-use entry point, allowing labs to test PPC performance in their specific workflows before committing to bulk quantities, or to maintain a small standing stock of PPC tubes alongside a primary PP or PS tube inventory.