Heathrow Scientific 15 mL Sterile Conical Tubes - HS4426 Series | DNase/RNase-Free, 3-Year Sterility

The 15 mL conical is the most-consumed sterile tube format in cell biology — used for every cell wash, pellet, resuspension, and sample transfer that moves between the biosafety cabinet and the centrifuge multiple times per day. Heathrow Scientific 15 mL Sterile Conical Centrifuge Tubes (HS4426B, HS4426R, HS4428) are individually gamma-irradiated to SAL 10⁻⁶ with a 3-year sterility expiration, certified DNase/RNase-free by lot, and available in the three configurations that match how labs actually work: natural bulk-wrap (HS4426B) for standard bench use, natural racked (HS4426R) pre-loaded in chipboard racks of 50 for tissue culture and high-throughput workflows, and opaque black (HS4428) for light-sensitive sample processing where a clear tube introduces measurement error that no downstream correction can fix. All three share the same 0.5 mL graduation intervals, 11,000 × g RCF rating, and lot-traceable easy-tear packaging.

Features and Benefits

• Individually gamma-irradiated, 3-year sterility expiration (SAL 10⁻⁶) — the same sterility assurance level as radiation-sterilized medical devices; the 3-year shelf life means bulk case purchases don't expire before use in most lab environments, justifying the per-case cost savings of volume buying

• Leak-proof polyethylene screw cap tested under centrifugal load — cap threads torque-tested to maintain seal integrity up to 11,000 × g; sample loss during centrifugation is a non-negotiable failure mode in clinical, bioprocessing, and regulatory-facing applications

• DNase/RNase-free certified by lot — documentation available — RNA-seq, RT-PCR, and mRNA extraction workflows use 15 mL conicals at critical steps where nuclease contamination at the tube level introduces assay variability that PCR amplification cannot distinguish from sample biology

• 0.5 mL graduation intervals to 15 mL — imprinted, not surface-printed — imprinted graduations survive alcohol wiping, water bath immersion, and autoclave cycles without fading or rubbing off; accurate volume reference at every liquid handling step without re-marking

• Racked format (HS4426R) uses recyclable chipboard — 10 racks × 50 tubes — chipboard racks go straight from storage to biosafety cabinet to centrifuge without intermediate tube handling; reduces single-use plastic waste compared to polypropylene rack formats from other suppliers

• Black configuration (HS4428) blocks visible light at the tube wall — opaque polypropylene protects fluorescent staining panels, luciferase reporter substrates, and bioluminescent samples through centrifugation, incubation, and brief bench storage without foil-wrapping workarounds

• Lot-to-lot traceability with easy-tear packaging — lot number on every bag and rack links to production and certification records; satisfies CLIA documentation, ISO 9001 QMS records, and GMP chain-of-custody requirements for regulated research manufacturing

Specifications

Laboratory Applications

• Cell Culture — Passaging & Washing (Natural, Bulk or Racked) — spin mammalian cells at 300–400 × g for pellet-wash-resuspend cycles during media exchange and passaging; the racked format eliminates tube handling in the biosafety cabinet where both hands are needed for decant and resuspension; the 3-year sterility expiration supports case-quantity purchasing for high-volume tissue culture rooms

• Bacterial Cell Harvest & Lysis — pellet overnight bacterial cultures at 4,000–6,000 × g for plasmid miniprep, protein expression harvest, or competent cell preparation; the 11,000 × g rating handles the high-speed clarification steps in bacterial lysis protocols without tube deformation or cap seal failure

• Clinical Sample Processing — Serum & Plasma Separation — collect whole blood fractions or urine sediment for research assays; the leak-proof cap satisfies OSHA bloodborne pathogen containment requirements; lot traceability supports CLIA documentation for clinical research laboratories

• Immunoassay & Flow Cytometry Sample Prep (Black, HS4428) — fluorescent antibody staining panels for flow cytometry require 30–60 minute incubations at 4°C where photobleaching of PE, FITC, and APC conjugates measurably reduces signal in clear tubes; black conicals maintain staining signal through the full prep-to-acquisition workflow

• Bioprocessing & Seed Culture Scale-Up — 15 mL conicals are the standard seed vessel in microbial and mammalian bioprocessing scale-up trains; DNase/RNase-free certification and lot traceability meet GMP cell banking and process development documentation requirements

Frequently Asked Questions

What is the practical difference between bulk-wrap and racked — when does the format matter?
Bulk-wrap (HS4426B, $160) arrives in a sealed bag — tubes pulled individually as needed; right for bench protocols where you pull 5–20 tubes at a time. Racked (HS4426R, $160) arrives with 500 tubes pre-loaded in 10 chipboard racks of 50 — carry the rack from storage to the biosafety cabinet to the centrifuge without intermediate handling; right for tissue culture rooms and high-throughput processing lines. Both are the same tube, same certification, same price. Format is a workflow decision only.

What is the maximum centrifuge speed I can use with these tubes?
Maximum rated RCF is 11,000 × g for all three configurations. Mammalian cell pelleting (300–400 × g) and bacterial harvest (4,000–6,000 × g) are both well within this range. For applications requiring forces above 11,000 × g, use microcentrifuge tubes or ultracentrifuge-rated formats — 15 mL polypropylene conicals from any manufacturer are not designed for ultra-high-speed centrifugation.

Are these tubes compatible with all standard 15 mL conical centrifuge rotors?
Yes. These tubes conform to the standard 15 mL conical geometry (17 mm outer diameter, 120 mm height) and fit 15 mL rotor positions in Eppendorf, Thermo Fisher, Beckman Coulter, Hettich, and other major centrifuge rotor lines. For non-standard rotors, verify the tube OD and height against your rotor's tube position specifications before use.

The sterility expiration is 3 years — can I trust tubes approaching their expiration date?
The 3-year sterility guarantee is validated for tubes stored correctly — room temperature, away from UV light, in original sealed packaging with intact seals. Tubes meeting these storage conditions and used before the printed expiration date fully comply with their sterility claim. Always inspect the packaging seal integrity before use — any compromised seal voids the sterility claim regardless of expiration date.

Quality Assurance

Heathrow Scientific 15 mL conical tubes are gamma-irradiated to a sterility assurance level of 10⁻⁶ with a 3-year sterility expiration from the date of manufacture. DNase/RNase-free certification is documented per lot with records available for quality and regulatory submissions. The HS4426R racked format uses recyclable chipboard racks. The HS4428 black variant is manufactured in Taiwan to identical certification standards as the natural China-manufactured variants. All tubes comply with ISO general labware standards for polypropylene centrifuge tube geometry and performance.

Academic and Institutional Pricing

LabSupplies.com offers tiered quantity pricing for academic and research institutions. As an authorized dealer, we ship directly from USA inventory.