ELA CHEMSTRIP
COVID-19

This new molecular diagnostic test for the virus that causes COVID-19 was developed by a strategic partnership between two biotech companies —Chemtest Argentina S.A. and Productos Bio-Lógicos S.A. (PB-L)— and the National Universities of San Martín (UNSAM) and Quilmes (UNQ).

The test kit is entirely manufactured in Argentina from national and imported materials. Over 80% of its components are made in Argentina.

ELA CHEMSTRIP® COVID-19 was designed to amplify a specific region in the SARS-Cov2 genome. This region is present in all the isolates that infect humans.

STEP 1 involves Easy Loop Amplification (ELA). This technique, entirely developed in Argentina, consists of isothermal amplification in a simple loop. This is why the ELA reaction is performed at a constant temperature of 60°C in a dry block heater with heated-lid for 1 hour. It does not require thermal cyclers or sophisticated equipment.

STEP 2 involves the immunochromatographic detection of the amplified products using CHEMSTRIP reactive strips.

If the ELA reaction amplifies the viral genome, this amplicon will flow across the membrane, and two visible purple-red bands will appear after 10 minutes (not more). This means that the result is POSITIVE FOR COVID-19.

If only one purple-red band appears after 10 minutes, it means that the result is NEGATIVE FOR COVID-19.

ELA CHEMSTRIP® COVID-19 can be used in low-complexity labs for the rapid and early detection of SARS-Cov2, using a simpler diagnosis method than conventional real-time PCR. Results are simple to read and easy to interpret. For all these reasons, ELA CHEMSTRIP® COVID-19 is the ideal test for decentralized implementation at healthcare facilities with insufficient infrastructure.

ELA CHEMSTRIP® COVID-19 provides a unique double-control system (reaction and extraction), minimizing false-negative rates.

ELA CHEMSTRIP COVID-19 uses a specific probe for SARS-Cov2 that eliminates the risk of false-positive results. With this method, only the amplified genetic material belonging to this virus can be detected by the CHEMSTRIP reactive strips with a 100% specificity.

Every molecular test based on gene amplification has a potential risk of yielding false-negative results due to issues in the extraction and purification of RNA material from the swab.

In order to minimize this risk, and in addition to the negative and positive controls included in the test kit, ELA CHEMSTRIP COVID-19 incorporates an internal control (RNase P gene) that must be added to the swab at the beginning of the purification process. This guarantees that a negative result is not caused by errors or issues during RNA purification. With this additional control, the sensitivity of the test —including the extraction process— is higher than 95%.

ELA CHEMSTRIP COVID-19 is a diagnostic test with high analytical sensitivity—it detects 25 to 100 viral RNA molecules.

ELA CHEMSTRIP COVID-19 requires simple equipment such as micropipettes, microcentrifuges, a dry block heater with heated-lid (60°C) and timer. It is extremely important to have two different and separate areas to perform the test. The ELA reaction must be carried out in AREA 1; the CHEMSTRIP detection must be performed in AREA 2. To avoid contamination, it is essential that no materials are exchanged between AREA 1 and AREA 2. There must be a unidirectional flow of materials. Once the test is completed, it is advisable that AREA 2 be cleaned with an oxidizing agent such as bleach or chlorinated water. UV light is recommended as decontamination method for tabletop surfaces in AREA 2.