30–50 mL Freestanding Centrifuge Tubes, Screw Cap Compatible, PPC, Natural — 200/Bag
These 50 mL freestanding centrifuge tubes are molded from Polypropylene Copolymer (PPC) and supplied natural (translucent) in a convenient 200/Bag pack for high-throughput lab workflows. PPC delivers improved optical clarity over standard homopolymer polypropylene, allowing direct visual inspection through the tube wall, along with enhanced cold-temperature flexibility suited to refrigerated and frozen storage. The flat freestanding base keeps tubes upright throughout the entire sample preparation workflow — no rack required — and each tube takes a Caplugs Evergreen 300-3541 screw cap, sold separately.
Sold without caps. These tubes ship uncapped in bulk. Close them with Caplugs Evergreen 300-3541 screw caps, sold separately in 1000-cap bags in eight colours.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 220-3550-080 |
| Capacity | 50 mL |
| Geometry | Freestanding base, centrifuge tube body |
| Material | Polypropylene Copolymer (PPC) |
| Color | Natural (translucent) |
| Cap | Not included — use 300-3541 screw caps |
| Sterility | Non-Sterile |
| Pack Size | 200/Bag |
| BPA / Phthalate / Latex | BPA-Free, Phthalate-Free, Latex-Free |
| Country of Origin | USA |
Applications
- Cell culture harvest — freestanding format supports rack-free bench handling during large-volume suspension culture aliquoting at the 50 mL scale
- Bulk reagent and buffer preparation — flat base holds tubes upright without a rack through weighing, mixing, and dispensing steps
- Large-volume solid-phase extraction (SPE) eluate collection — PPC clarity allows direct visual monitoring of eluate volume and color; full compatibility with acetonitrile and methanol eluents
- Density gradient centrifugation — 50 mL capacity accommodates Ficoll® and Percoll® gradient protocols in swing-bucket or fixed-angle rotors (verify rotor accepts this tube format)
- Water bath incubation — PPC thermal rating supports incubation up to approximately 80°C
- Cold storage — improved cold-temperature flexibility versus homopolymer PP makes these tubes well suited to 4°C and −20°C storage; excellent performance at −80°C
- Bench centrifugation — use in a 50 mL conical adapter at up to 3,000 × g (verify that the rotor accepts the freestanding-base geometry)
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Aqueous buffers / saline (pH 2–12) | Excellent |
| Dilute acids / bases (<10%) | Excellent |
| Methanol / acetonitrile (<100%) | Excellent |
| Ethanol / isopropanol (<100%) | Excellent |
| Cell culture media | Excellent — low protein-binding |
| Cold storage (−80°C) | Excellent — improved flexibility vs. homopolymer PP |
| Ethyl acetate | Limited — short-term contact only; avoid prolonged exposure |
| Dichloromethane / chloroform | Not compatible — causes cracking; do not use |
Quality & Procurement
Made in USA, these Caplugs® Evergreen centrifuge tubes are manufactured from FDA-compliant, BPA-free, phthalate-free, latex-free PPC resin under ISO 9001 quality management. LabSupplies.com is an authorized dealer and ships from USA inventory, typically same business day for stocking items.
Frequently Asked Questions
Are these centrifuge tubes sterile?
No — the 220-3550-080 tubes are supplied non-sterile. For workflows that require a sterile tube, consider gamma-irradiated alternatives or autoclave these tubes prior to use, keeping in mind the PPC thermal rating of approximately 80°C for liquid-cycle autoclaving.
What is the advantage of PPC over standard polypropylene for centrifuge tubes?
Polypropylene Copolymer (PPC) offers meaningfully better optical clarity than homopolymer PP, so you can visually inspect sample level, pellet formation, or eluate color directly through the tube wall. PPC also maintains greater flexibility at low temperatures, making it a better choice for cold-room centrifugation and frozen storage applications.
Is the screw cap included, and what type does this tube accept?
Screw caps are sold separately. This tube takes the Caplugs® Evergreen 300-3541 cap for 50 mL tubes, sold 1000 to a bag in eight colours.
Can these tubes be used in a standard bench centrifuge for cell culture harvest?
Yes. These freestanding 50 mL tubes are suited to bench centrifugation up to approximately 3,000 × g using a rotor with a 50 mL conical adapter. Because the flat freestanding base differs in geometry from standard conical-bottom tubes, always verify that your specific rotor accepts this tube format before centrifuging.
