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One-step Strep-A Rapid Test

Our rapid strep-A test cassettes are widely used in clinical labs as an aid in diagnosis of upper respiratory infectious diseases.

Strep-A Antigen Rapid Test Cassette

Intended Use

Strep-A rapid test Kits, also known as one-step strep A tests, are a lateral flow, one-step immunoassay for the rapid, qualitative detection of Group A Streptococcus antigen in human throat swab specimens. Our rapid strep-A test cassettes are widely used in clinical labs as an aid in diagnosis of upper respiratory infectious diseases such as tonsillitis, pharyngitis and scarlet fever.

Merits of Strep-A Rapid Test

It has been proved that early diagnosis and treatment of Group A Streptococcal pharyngitis can reduce the severity of the symptoms and avoid further complications, such as rheumatic fever and glomerulonephritis. The conventional testing methods used for the detection of these diseases depend heavily on the isolation and subsequent identification of the organism. This process often requires 24 - 48 hours to get the testing result. With one-step strep-A diagnostic test cassettes, we can detect Group A Streptococcal antigen directly from throat swabs, and the preliminary testing result can be got within as short as 5 minutes. In this way, this rapid Strep-A immunoassay test device allows physicians to diagnose and administer therapy immediately, thus help cure the patients and improve the health conditions.

Testing Principle of Strep-A Rapid Test

When testing with a strep-A test cassette, the Strep A antigen from specimen, if any, will react with colored antibody-colloidal gold conjugate to form Strep A antigen-antibody-conjugate compounds. The mixture then moves chromatographically across the membrane to the test line region where rabbit anti-strep A antibody is pre-coated, and compounds are captured by the binded antibody, a pink band thus appear. If there are no antigen in the specimen, the colloidal gold will not accumulate at the test region and no color will emerge, indicating a negative result..

Streptocoaus-A Test Kits: Principle, Packing...

Cat. No. Description (& Details) Specimen PCS/Box Quan. per CTN Quantity (Tests)
STRP 451 Strep-A Test Cassette Throat & Nasal Swab 20 Bulk: 1200 PCS
Boxed: 40 Boxes
How to Use

Strep-A Test Cassette

General Information

(IVD Kit »-» Respiratory Tract Disease -» One Step Lateral Flow Immunochromatographic Assay)

Catalog No.:STRP 451
Description:Strep-A Test Cassette
Category:Respiratory Tract Disease
Specimen:Throat & Nasal Swab
No. of Step:One Step
Reading Time:5 Minutes
Cut Off:250K Organism/Test
Specification:5.0 mm
Quan. or Qual.:Qualitative
Method:Lateral Flow Double Antibody Sandwich

Packing Specification

Tests per Kit:20 Tests
Box Dimension:21.0 * 12.5 * 6.5 CM
Kits per CTN:40 Kits
Carton Dimension:53 * 45 * 36 CM
Tests per CTN (BULK):1200 Tests
Carton Volume:0.085 CBM
GW per CTN (Boxed):14.0 KG
GW per CTN (Bulk):15.0 KG

Materials Provided in the Test Kit

  • Strep-A Ag Cassette in individual foil pouch;
  • Extraction Reagent A: NaOH (5ml);
  • Extraction Reagent B: Acid (5ml);
  • Extraction Reagent C: Oxidation Reagent (5ml);
  • Sterile Throat Swabs: 20PCS;
  • Plastic Pipette for sample transfer;
  • Instruction leaflet for use.


Throat Swab

To collect a throat swab specimen, vigorously rub a rayon throat swab on both tonsillar surfaces and the posterior pharynx.

Remove swab from mouth and insert, tip down, into paper wrapper.

Nasal Swab Specimen

Use the sterile swab supplied in the kit. Insert this swab into the nostril that presents the most secretion under visual inspection.

With gentle rotation, push the swab until resistance is met at the level of the turbinates (less than one inch in the nostril). Rotate the swab three times against the nasal wall.

Or, insert the swab into nostril parallel to the palate and leave in place for a few seconds to absorb specimens.

Throat & Nasal Swab Storage Condition

It is recommended that swab specimens be processed as soon as possible after collection.

If swabs are not processed immediately they should be placed into a dry, sterile, and tightly sealed plastic tube for storage. Swabs can be stored dry at room temperature for up to 24 hours.

Testing Principle of Lateral Flow Double Antibody Sandwich

GICA Double Antibody Sandwich Method Illustration

In the double antibody sandwich lateral flow chromatographic rapid test, two antibodies are used to detect viral protein or antigen.

In the test band region, antibody specific to the target antigen or protein is immobilized. In the end of the membrane strip where the samples are added, another antibody conjugated with colloidal gold particles is embedded.

During the testing process, specimen from the patient is added to the end of the membrane strip. The antibody conjugate particles will resolve into the specimen, where the antibody conjugate will react and bound to the target protein or viral antigen, if present.

This antigen-antibody conjugate complex then moves along the strip to the testing band region, under capillary effect. The immobilized antibody in the test line region then bound to another binding site on the antigen complex, and the antibody-antigen-antibody complex is fixed on test band region.

When the complex congregates, the highly concentrated colloidal gold particles will develop some red or pink color, indicate a positive result.

If there is no target protein or antigen in the specimen, the colloidal gold particles will not congregate and no color will develop, indicating a negative result.

Information | Packing | Specimen | Principle