MUHWA 2mL Microcentrifuge Tubes — Graduated, Round Bottom, 500 pcs/Pack

MUHWA 2mL Microcentrifuge Tubes — Round Bottom, Graduated, 500/Pack

These are the tubes you reach for when the protocol says "transfer to a 1.5mL tube" but you know there's going to be boil-over at 95°C if you fill past 1.2mL. The extra capacity of a 2.0mL tube gives you headspace — keep your reaction volume at 1.5mL or below and the tube handles a denaturation step at 95°C without the cap popping open from vapor pressure.

The round bottom matters more than you'd think. After centrifugation at 14,000 rpm, your pellet collects in a tight, visible spot at the very bottom — not smeared up the conical wall the way it sometimes does in skirted tubes. When you're doing small-scale DNA preps or protein precipitations, a visible pellet is the difference between knowing you've got product and guessing. The round bottom also resists cracking better than conical designs at high g-forces — the stress distributes evenly across the curved surface.

Common applications in the lab

These 2mL tubes slide into daily workflows across molecular biology and biochemistry benches. Use them for PCR and qPCR master mix preparation — the 2.0mL volume holds your cocktail plus template comfortably. They work for restriction digests, ligation setups, and small-volume enzyme reactions. In protein work: cell lysate clarification spins, TCA/acetone precipitations, and short-term sample storage at -20°C or -80°C. The round bottom also works well for sonication — the curved geometry transmits ultrasonic energy with fewer dead zones than a conical bottom, useful during chromatin shearing or cell disruption.

Cap design that clicks

The snap cap has an audible and tactile click when it closes properly. You can feel it through your glove and hear it across the bench. Push down until you get that click, and the tube is sealed — the cap won't spontaneously open during a 30-minute incubation at 65°C, and it holds at -80°C without the plastic relaxing and breaking the seal. To open, use the small thumb tab — it's positioned so you can flick it open one-handed with your thumb while holding a pipette in the other hand.

Graduations you can actually read

Molded-in volume marks at 0.5, 1.0, 1.5, and 2.0mL. The graduations are raised, not printed — they don't wash off with ethanol or fade after repeated autoclaving. Under good bench lighting they're visible enough to estimate volume within about 0.1mL. Not a replacement for a pipette, but useful for quick checks: "Do I have about 500µL of supernatant here?"

RNase/DNase-free production

The tubes come certified free of detectable RNase and DNase activity. They're packaged in resealable bags of 500. Open the bag, use what you need, seal it back up — no need to decant into a separate container where they'd pick up dust and nucleases from the air. If your lab is strict about nuclease control, these go straight from the bag into your PCR hood or RNA bench without an intermediate handling step.

Specifications

Centrifugation notes

Always use a rotor that fully supports the tube wall — at 14,000+ rpm an unsupported 2mL tube can deform. Standard 24-place and 30-place microcentrifuge rotors provide this support. If you're spinning at less than 10,000 x g, the round bottom handles it without issue. For phenol-chloroform extractions: the PP resists the organic phase during the short contact time of a spin, but don't store phenol in these tubes long-term — the plastic will slowly swell. Common lab solvents — ethanol, isopropanol, DMSO at typical working concentrations, and mild acids/bases at bench concentrations — are compatible for standard protocol durations. Avoid prolonged contact with concentrated strong acids and chlorinated solvents beyond the brief exposure of an extraction spin.