This is how the viral video of the antigen test that tests positive with an orange is explained

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to detect coronavirus

have gone viral on WhatsApp and social networks .

This is not something new, and although a few months ago a similar video was already circulating trying to question the

, its impact and dissemination were very limited since they were hardly sold in pharmacies.

Taking advantage of the pull of the tests at Christmas, the

of the tests have resurfaced.

What is seen in the videos?

In case you haven't seen them, they show an anonymous person

.

In other videos they perform the same action with apple juice, urine, tap water and even beer.

While they misuse the test and the

is coming out , they send a message warning the population that they are a scam, they are useless and even encourage them not to get vaccinated.

What's the score?

Although two marked lines appear and we can think that it is positive, in reality

since at no time are the operating instructions of the test being followed.

The reagent liquid inside the box, the buffer, is not used, nor is a nasal sample collected with the

.

It would be like holding a thermometer up to a light bulb and saying you have a fever.

Why are the two lines of the test marked?

The key is in the

.

Although it may not seem like it, these tests are very sensitive since the proteins they contain need very specific conditions to work correctly.

The buffer, the reagent, is responsible for maintaining the sample that we deposit on the test within these optimal conditions, which will correct the pH of the sample so that it is in the appropriate range.

If we use anything as a sample, and on top of that we don't use the reagent,

What is the test reagent for?

The small container with liquid included in the test boxes is an essential reagent for the operation of the test.

Its function is to give the sample a liquid form so that the test paper strip can absorb it (if we bring the swab with the nasal mucosa sample close to the test it will not work) and to prevent the sample from having a pH too acidic or too basic.

But the reagent has a range of efficacy, if we use it with juices or any other very acidic or very basic liquid

Another of the viral images shows an open test where there is only a strip of paper inside.

What is suposed to be?

Precisely what there is, is all there is to be.

We do not need anything else for the test to work, and in reality the plastic casing that covers the strip is nothing more than a piece to make its use more comfortable.

We could paint it in colors or put lights on it, but

What is on that strip of paper?

We all know it as coronavirus antigen test, but its real name is

The strip is made of

and is impregnated with modified antibodies labeled with a colored substance.

The drops of the reagent mixed with the nasal sample are deposited in the lower part of the strip, and the liquid rises by capillarity along the strip.

How does the test work?

As I said, the liquid rises along the strip until it reaches the upper area.

But on that path it will find the

, and if there is a coronavirus in that solution that we have obtained after mixing a sample from our nasal mucosa with the reagent, the virus antigens will bind to those modified antibodies and the virus will appear. colored reaction.

Are similar tests used to detect other things?

Of course it has, and for years.

The operating system is similar to that of rapid tests for many other respiratory viruses such as influenza or syncytial virus, also for rapid HIV tests or even

.

Its operation seems simple, but these tests are a miracle of science in miniature, the result of years of research.

According to the criteria of The Trust Project

Know more

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