Ria Vial

Quick Answer: An RIA vial is a small, usually round-bottomed plastic tube used to hold samples and reagents in radioimmunoassay, where the tubes go straight into a gamma counter after the assay. The same vials serve for other immunoassays, serology and small-volume sample handling.

How the Vial Is Used in an Assay

In a typical radioimmunoassay, a fixed amount of antibody and iodine-125 labelled antigen is added to each tube together with standards or patient samples. After incubation the bound antigen is separated, often by precipitating the antibody complex, spinning the tubes and decanting the liquid, and each tube is then placed in a gamma counter. The vial therefore has to hold the reaction and fit the counter’s racks.

Vials in this format are made in polystyrene, which is clear, and in polypropylene, which resists more chemicals and binds some proteins differently. The size most often used is 12 x 75 mm, but the dimensions and material of this listing should be checked against your counter and protocol.

Outside radioisotope work, the same small tubes are used for blood grouping and cross-matching practicals, agglutination tests and preparing cell suspensions. For incubations that need closing, fit a flip-top cap to keep the tubes covered.

Specifications

Applications

• Radioimmunoassay of hormones in research and teaching labs
• Tube-method blood grouping and antibody screening practicals
• Agglutination and precipitation tests in immunology classes
• Preparing small cell suspensions for counting or staining

Care & Handling

• Run radioactive assays in the designated area and follow your radiation safety rules for waste.
• Write sample numbers high on the vial so labels are not lost in a water bath.
• Handle polystyrene vials gently; they crack if dropped or spun too hard.
• Do not autoclave polystyrene vials; discard them after a single use.

Why Choose LabEquip

Immunology and clinical biochemistry teaching labs, blood-bank training courses and research groups running tube-based assays order them in bulk. LabEquip lists them in the Biology Lab Products range; specify size and material through the contact page.

Frequently Asked Questions

Is an RIA vial the same as a test tube?

It is a small test tube made for assay work. These vials are narrower and shorter than standard school test tubes and are plastic so they can be discarded after one use and fit counter racks.

Should I choose polystyrene or polypropylene vials?

Polystyrene is clearer, which helps when reading agglutination or precipitates by eye. Polypropylene resists more solvents and tolerates autoclaving. Some assays specify one material because proteins bind differently to each surface.

Can these vials be used without radioactivity?

Yes. The format is widely used for non-radioactive immunoassays, blood grouping, serology and cell suspension work. The name only reflects the assay they were first made for.

Can the vials be centrifuged?

Yes, at the moderate speeds used in serology and assay separation steps, provided they sit in a suitable centrifuge carrier. Polystyrene is more brittle than polypropylene and can crack at higher speeds.

How are used assay vials disposed of?

Vials from radioimmunoassay go into radioactive waste according to your licence conditions. Vials used with blood or serum are treated as biohazardous waste and autoclaved or incinerated.

Do RIA vials come with caps?

Many are supplied open, with push-on or flip-top caps sold separately for incubation and storage. Whether caps are included in this listing is confirmed at enquiry.

Last Updated: September 2026