16 mL Round Bottom Test Tubes with Two-Position Snap Caps — PS, Natural, Sterile, 25/Bag (222-2094-050)
These 16 mL polystyrene round bottom test tubes measure 17 × 100 mm and ship sterile, 25 per bag, unassembled — tubes and caps packaged separately for assembly immediately before use. The round bottom geometry concentrates cell pellets and precipitates at the tube base for efficient resuspension and aspiration after centrifugation, while the two-position snap cap enables vented operation for gas exchange during incubation or a sealed configuration for containment during transport. Part number 222-2094-050 is a workhorse format for flow cytometry, FACS analysis, and clinical sample preparation workflows.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 222-2094-050 |
| Volume | 16 mL |
| Dimensions | 17 × 100 mm |
| Bottom Style | Round Bottom |
| Cap Type | Two-Position Snap Cap (Vented / Sealed) |
| Assembly | Unassembled |
| 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 — standard 17 × 100 mm round bottom PS format accepted by most cytometer sample probes
- Immunofluorescence staining — optical clarity of PS supports direct visual inspection and compatibility with fluorescent dyes and stains
- Cell sorting — round bottom concentrates pellets for efficient post-centrifugation resuspension
- Hematology sample preparation — 16 mL capacity accommodates typical blood-based workflows
- Serological and agglutination assays — round bottom format ensures consistent reaction zone at tube base
- Specimen collection and general sample handling requiring a sterile, capped tube with vented incubation capability
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Aqueous buffers / saline | Excellent |
| Dilute acids | Excellent |
| Dilute bases | Excellent |
| Methanol | Compatible — verify concentration and contact time |
| Isopropanol | Compatible — verify concentration and contact time |
| Acetonitrile | Compatible — verify concentration and contact time |
| Aromatic / chlorinated solvents | Not recommended — PS is not solvent-resistant |
| Acetone | Not recommended |
| Autoclaving | Not suitable — PS is not autoclavable |
Quality & Procurement
Made in USA, these Caplugs® Evergreen tubes are produced at ISO-certified facilities from virgin-grade, FDA-registered polystyrene resin that is BPA-free and phthalate-free. Sealed bag packaging maintains sterility from receipt through point-of-use, and lot-level quality controls ensure consistent tube geometry, wall thickness, and dimensional uniformity across every unit in the bag. LabSupplies.com is an authorized Caplugs® Evergreen dealer, shipping from USA inventory with tiered pricing available for high-volume institutional, clinical, and research accounts.
Frequently Asked Questions
Are these tubes supplied already assembled with the caps attached?
No — the tubes and snap caps are packaged separately within the bag and are intended for assembly immediately before use. This unassembled format preserves sterility and prevents cap deformation during storage and shipping.
What does the two-position snap cap do?
The snap cap has two locking positions: a vented position that allows gas exchange for cell incubation workflows, and a fully sealed position for containment during centrifugation or transport. Switching between positions requires no tools.
Are these tubes suitable for use on an automated flow cytometer sample handler?
The 17 × 100 mm round bottom format is the standard geometry accepted by most flow cytometer and FACS sample probes, but you should confirm your specific instrument's tube dimension requirements before switching from your current supply.
Can these tubes be autoclaved or used with acetone-based reagents?
No — polystyrene is not autoclavable and is not compatible with acetone or aromatic and chlorinated solvents. These tubes ship sterile and are intended for single-use applications with aqueous buffers, biological stains, and the other compatible reagents listed in the chemical resistance table above.