8.0 mL Round Bottom Test Tubes with Natural Screw Caps — PS, Sterile, 13 × 100 mm (222-2068-05I)
These 8.0 mL polystyrene round bottom test tubes ship individually packed with natural screw caps, offering a leak-resistant threaded closure ideal for specimen containment, transport, and analytical workflows. Measuring 13 × 100 mm, the round bottom geometry concentrates cell pellets and precipitates at the tube base for efficient resuspension and aspiration after centrifugation. Each tube arrives sterile in sealed individual packaging, maintaining integrity from receipt through point-of-use.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 222-2068-05I |
| Volume | 8.0 mL |
| Dimensions | 13 × 100 mm |
| Bottom Style | Round Bottom |
| Cap Type | Natural Screw Cap |
| Material | Polystyrene (PS) |
| Color | Natural |
| Sterility | Sterile |
| Pack Size | 1/Individually Packed |
| BPA / Phthalate Free | Yes |
| Country of Origin | USA |
Applications
- Flow cytometry and FACS analysis — the round bottom format and PS optical clarity are standard requirements for fluorescent cell analysis platforms
- Immunofluorescence staining — transparent PS walls allow direct visual inspection of stained cell populations
- Cell sorting — round bottom concentrates sorted populations for downstream recovery
- Hematology sample preparation — the 8.0 mL, 13 × 100 mm format accommodates standard blood-derived sample volumes
- Serological and agglutination assays — round bottom geometry supports consistent reaction pooling
- Specimen collection and clinical transport — threaded screw cap provides superior leak-resistance compared to snap-cap formats
- General laboratory sample storage requiring a sterile, individually packaged tube
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Aqueous buffers / saline | Excellent |
| Dilute acids | Excellent |
| Dilute bases | Excellent |
| Methanol | Compatible |
| Isopropanol | Compatible |
| Acetonitrile | Compatible |
| Aromatic / chlorinated solvents | Not recommended |
| Acetone | Not recommended |
| Autoclave | Not suitable — PS is not autoclavable |
Quality & Procurement
Made in USA at ISO-certified Caplugs® Evergreen manufacturing facilities, these tubes are produced from virgin-grade, FDA-registered polystyrene resin and are certified BPA-free and phthalate-free. Lot-level quality controls ensure consistent tube geometry, wall thickness, and dimensional uniformity across every individually packed unit. LabSupplies.com is an authorized Caplugs® Evergreen dealer, shipping from USA inventory with tiered pricing available for high-volume institutional, clinical, and grant-funded laboratory accounts.
Frequently Asked Questions
Are these tubes sterile, and how is sterility maintained?
Yes — each tube is individually packed in sealed packaging that preserves sterility from the point of manufacture through point-of-use, making them suitable for cell culture, clinical specimen collection, and other contamination-sensitive workflows.
Are these tubes compatible with flow cytometry instruments?
Yes. The 13 × 100 mm round bottom PS format is the standard tube geometry accepted by most flow cytometry and FACS platforms. The polystyrene construction offers the optical clarity required for fluorescent dye and stain compatibility in cell analysis workflows.
Why choose a screw cap over a snap cap for this tube size?
The threaded natural screw cap creates a more secure, leak-resistant seal than snap-cap designs, which is especially important during specimen transport, centrifugation, and storage of liquid samples in an 8.0 mL tube.
Can these tubes be autoclaved or used with organic solvents?
No. Polystyrene is not autoclavable and is not recommended for use with aromatic solvents, chlorinated solvents, or acetone. These tubes are well suited for aqueous buffers, dilute acids and bases, and short-term contact with lower-concentration alcohols such as methanol and isopropanol.