8.0 mL Round Bottom Test Tubes with Natural Screw Caps — PS, Sterile, 13 × 100 mm (222-2068-050)
These 8.0 mL polystyrene round-bottom test tubes ship sterile in 25/Bag packs and are supplied unassembled — tubes and caps packaged separately — so your team can assemble them immediately before use for maximum flexibility. At 13 × 100 mm, the round-bottom geometry concentrates cell pellets and precipitates at the tube base for efficient resuspension after centrifugation, while the natural screw cap delivers a leak-resistant threaded closure suited for specimen transport and storage. The optical clarity of virgin-grade PS makes these tubes a natural fit for flow cytometry, fluorescence-based assays, and any workflow where visual sample inspection matters.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 222-2068-050 |
| Volume | 8.0 mL |
| Dimensions | 13 × 100 mm |
| Bottom Style | Round Bottom |
| Cap Type | Natural Screw Cap |
| Assembly | Unassembled (tubes and caps packaged separately) |
| Material | Polystyrene (PS) |
| Color | Natural |
| Sterility | Sterile |
| Pack Size | 25/Bag |
| BPA / Phthalate Free | Yes |
| Country of Origin | USA |
Applications
- Flow cytometry and FACS analysis — round-bottom PS is the standard format for most cytometer sample introduction systems
- Immunofluorescence staining and cell sorting, benefiting from PS optical clarity and consistent tube geometry
- Hematology sample preparation and serological / agglutination testing in the 13 × 100 mm format
- Specimen collection and clinical specimen storage where a leak-resistant screw cap is preferred over snap-cap formats
- General laboratory sample handling requiring sterile, single-use tubes with defined round-bottom pellet geometry
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Aqueous buffers / saline | Excellent |
| Dilute acids | Good |
| Dilute bases | Good |
| Methanol | Good — short-term contact |
| Isopropanol | Good — short-term contact |
| Acetonitrile | Good — short-term contact |
| Acetone / aromatic solvents / chlorinated solvents | Not recommended |
| Autoclave / heat sterilization | Not recommended — PS is not autoclavable |
Quality & Procurement
Made in USA, these Caplugs® Evergreen tubes are manufactured at ISO-certified facilities from FDA-registered virgin-grade polystyrene resin that is BPA-free and phthalate-free. Sealed sterile packaging maintains integrity from receipt through point-of-use, and lot-level quality controls ensure consistent tube geometry, wall thickness, and dimensional uniformity across every bag. LabSupplies.com is an authorized Caplugs® Evergreen dealer shipping from USA inventory, with volume and institutional pricing available for clinical laboratories, research institutions, and biotech organizations.
Frequently Asked Questions
Are the tubes and caps packaged together, ready to use?
No — part number 222-2068-050 is supplied unassembled, meaning tubes and caps are packaged separately within the bag. This allows you to assemble each tube immediately before use, which is common practice in flow cytometry and cell-sorting workflows to avoid any risk of pre-assembly contamination.
Are these tubes compatible with standard flow cytometers?
Yes. The 13 × 100 mm round-bottom PS format is widely recognized as the standard tube geometry for flow cytometry and FACS sample introduction. However, always verify the tube outer diameter and length against your specific instrument's sample carousel or tube holder specifications.
Can I autoclave these tubes?
No. Polystyrene is not autoclavable and will deform under high heat. These tubes are supplied sterile from the factory, so autoclaving is not necessary for standard sterile workflows.
Are these tubes certified RNase- and DNase-free?
The source data provided does not include a DNase/RNase-free certification for this product. Contact our team or request the current lot documentation to confirm suitability for nucleic acid work before use in sensitive molecular applications.