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Caplugs® Evergreen

50–100 µL Test Tubes, Round Bottom, PS, Natural, BD® Compatible — 222-2036-050 | 25/Bag | Caplugs® Evergreen

50–100 µL Test Tubes, Round Bottom, PS, Natural, BD® Compatible — 222-2036-050 | 25/Bag | Caplugs® Evergreen

Regular price $103.73
Regular price Sale price $103.73
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Quick Reference

Part Number 222-2036-050
Capacity 5.0 mL
Dimensions 12 × 75 mm
Material Polystyrene (PS)
Color Natural
Cap / Closure Two-position snap cap — clicks to vented or fully closed; ships unassembled
Sterility Sterile — individually or bag sterile-packed
Pack Size 25/Bag Unassembled
Key Use Flow cytometry (FACS), serology, blood bank tube testing
Origin Made in USA
Price $103.73/Bag ($4.1490/tube)

Technical Narrative

The Caplugs® Evergreen 222-2036-050 is a 5.0 mL Round Bottom PS Sterile Test Tube with Two-Position Snap Cap, 12 × 75 mm, 25/Bag Unassembled, sterile. The two-position snap cap clicks to two distinct positions: Position 1 (vented/partially open) — allows gas exchange during centrifugation, incubation, or culture; Position 2 (fully closed) — provides a sealed closure for storage, transport, and aerosol containment. Shipped unassembled — tube and caps are in the same bag but not pre-mated; the lab assembles each tube before use. This is the standard specification for bulk clinical serology and flow cytometry labs where assembly cost is preferred over individually pre-assembled units.

PS provides the optical clarity required for direct visual reading of agglutination reactions in tube serology — the test result is observed as a button, partial agglutinate, or dispersed cell pattern against the clear tube wall. PS also provides the low autofluorescence background important for fluorescence-based flow cytometry detection.

Procurement economics: $103.73/Bag, $4.1490/tube. Sterile 222-series round-bottom test tube siblings: 222-2036-05I (5.0 mL 12×75 mm Two-Position Snap Cap Individually Packed); 222-2012-010 (5.0 mL 12×75 mm Open Top 25/Bag); 222-2061-050 (8.0 mL 13×100 mm Two-Position Snap Cap 25/Bag Unassembled). LabSupplies.com ships from USA inventory, typically same business day.

Technical Specifications

Part Number
Caplugs Item #
Capacity 5.0 mL
Dimensions 12 × 75 mm
Geometry Round bottom
Material Polystyrene (PS)
Color Natural
Cap Two-position snap cap — vented and fully closed positions; unassembled
Sterility Sterile — individually or bag sterile-packed
Pack Size 25/Bag Unassembled
Application Flow cytometry, cell culture, serology requiring vented cap
BPA / Phthalate BPA-Free, Phthalate-Free, Latex-Free
Country of Origin USA
Price $103.73/Bag ($4.1490/tube)

5.0 mL 12×75 mm Sterile PS Round Bottom Tube Applications

The is the standard flow cytometry and serology tube. Compatible with the following platforms and protocols.

Application / Instrument Configuration Notes
Flow cytometer (FACS) Standard 12×75 mm tube holder (BD FACSCanto, LSR, Attune, CytoFLEX, etc.) Industry-standard 12×75 mm format — fits all major flow cytometer tube holders
Cell sorter 12×75 mm sample tube position Open-top or snap-cap for sample loading; cap removed for cell sorter nozzle
Tube serology (blood bank) Manual tube agglutination, centrifuge PS clarity for visual agglutination reading
Immunophenotyping Surface marker staining, lyse/wash protocol 5 mL capacity for standard staining volumes (50–100 µL sample + 200 µL reagents)
Cell culture / stimulation Short-term culture in incubator (snap-cap) Two-position snap cap: vented for CO2 exchange, closed for transport
Intracellular staining Fixation/permeabilization protocol PS: compatible with methanol, saponin-based protocols
Centrifugation Cell pellet, up to 600×g wash steps Round bottom: uniform cell pellet; sterile for downstream culture

Chemical Resistance — Polystyrene (PS)

Compatibility reference for PS at typical laboratory conditions.

Reagent / Condition Compatibility Notes
Aqueous buffers / saline Excellent PS compatible across pH 4–10 for standard biological assays.
Serum / plasma / whole blood Excellent Standard clinical and blood bank specimen matrix.
Formalin (10% NBF) Excellent PS compatible with standard fixative for flow cytometry fixation.
Methanol (<100%) Limited Short-term compatible for intracellular staining fixation steps.
Saponin / detergent buffers Good PS compatible with saponin-based permeabilization buffers.
Acetone / chloroform Not Compatible Dissolves PS; do not use.
DMSO (<1%) Good Compatible at concentrations used in cell culture and cryopreservation.
Flow cytometry reagents (FITC, PE, APC, etc.) Excellent PS: low autofluorescence in visible wavelength range for cytometry.

Clinical & Research Laboratory Applications

Caplugs® Evergreen 5.0 mL 12×75 mm sterile PS round-bottom tubes with two-position snap caps (unassembled) serve flow cytometry, cell culture, and serology laboratories requiring the standard 12×75 mm format with a re-sealable vented closure. The two-position snap cap is specified for cell culture and stimulation protocols in the tube format — Position 1 (vented) maintains a partially open cap during incubation in a CO2 incubator or rocker, allowing gas exchange while preventing aerosol contamination; Position 2 (fully closed) re-seals the tube for centrifugation, transport, and storage. The unassembled format is the cost-effective bulk specification for high-volume labs that prefer to assemble tubes at the bench.

U.S. Manufacturing, Quality & Institutional Procurement

Caplugs® Evergreen products are manufactured in the United States under ISO 9001 quality management from FDA-compliant, food-contact-grade resins. BPA-free, phthalate-free, and latex-free, with material-disclosure documentation supporting CAP, CLIA, and ISO 15189 laboratory accreditation audits.

LabSupplies.com is an authorized dealer for the full Caplugs Evergreen catalog and ships directly from USA inventory — typically same business day for stocking SKUs. We offer below retail pricing on volume orders, tiered institutional and academic pricing, and direct support for grant-funded laboratories and government procurement channels. Lab managers and procurement officers can request a written quote or speak with a product specialist directly from our sales engineering team.

Frequently Asked Questions

Are the test tubes sterile?

Yes. Sterile — individually or bag sterile-packed as specified. Maintain sterility until the bag or individual wrapper is opened.

What are the two positions of the two-position snap cap?

Position 1 (partially open/vented): the cap is clicked to the first position, leaving a small gap that allows gas exchange — used during incubation in CO2 incubators, aerobic culture, and centrifugation where pressure equalization is needed. Position 2 (fully closed): the cap clicks to a fully sealed position for storage, transport, and aerosol containment.

What does 'Unassembled' mean for the snap-cap tube?

Unassembled means the tube body and the snap cap are included in the same bag but are not pre-mated. The lab assembles each tube by pressing the cap onto the tube before use. This reduces per-tube cost vs individually pre-assembled units and is the standard specification for high-volume clinical and research labs.

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