I decided to first check the claims. I opened bottles of orange and cola juice, and then placed a few drops on LFTs. It was true, after a few moments, I saw two lines on each LFT, which supposedly indicated the presence of COVID-19.
Understanding how the tests are conducted is important. You’ll see a strip called nitrocellulose and a small, red pad hidden beneath the plastic casing of the LFT device. The red pad contains antibodies which bind the COVID-19 Virus. The antibodies are also attached to nanoparticles, which appear as red particles. You must mix the sample with the liquid buffer solution to ensure that the pH is optimal before you drip it onto the strip.
Fake positive results. Mark Lorch is the author.
Fluid wicks the nitrocellulose up and picks the gold and antibodies. If the virus is present, these antibodies will also bind it. More antibodies bind to the virus further up the strip. They are located next to the T for test. These antibodies can’t move because they are attached to the nitrocellulose. The virus is also grabbed by the second set of antibodies as the gold-labeled antibodies are passed over the red smear. The virus then binds to both antibodies, leaving the gold immobilised next to the T, which indicates a positive test.
The gold antibodies that are not bound to COVID-19 continue up the strip, where they encounter a third antibody set, which is not designed to detect COVID-19 and is stuck on the C line (for control). They trap the gold particles without the need to use the virus. This line indicates that the test was successful.
Acid test
How can a soft-drink cause a red T-line to appear? It is possible that soft drinks contain substances that antibodies recognize and bind, similar to viruses. This is unlikely. This is because antibodies are very particular in what they will bind to. The swabs that you use to collect snot from your nose and mouth are full of all kinds of things. These include viruses, proteins, and leftovers of breakfast. But the antibodies ignore it. They won’t react to the soft drink ingredients.
It is more likely that the drinks are affecting the function antibodies. The fluids used, from fruit to cola, all had one thing in common: they were highly acidic. Citric acid, found in orange juice and cola, and malic acid present in apple juice all have pH values between 2.5 and 4 due to their acidity. This is a harsh environment for antibodies. They have evolved to function primarily in the bloodstream with its pH of 7.4.
The buffer is crucial to the proper functioning of the test. It’s what you use with your sample, the liquid solution provided. The buffer plays a crucial role in the test. If you mix cola and the buffer, as demonstrated by debunking an Austrian politician who claimed that mass testing was worthless, then the LFTs will behave as expected: negative for COVID-19.
Without the buffer, antibodies are exposed to the acidic pH levels of the drinks. This has a dramatic impact upon their structure and functionality. Antibodies are proteins made up of amino acids that are attached to each other in long, linear chains. These chains are folded into specific structures. A small change in the chain can have a dramatic impact on a protein. The structure of a protein is maintained by thousands of interactions among the different parts. Positively charged areas will attract negatively charged portions of a protein.
In acidic conditions becomes more positively charged. The delicate structure of a protein is also affected, and the protein no longer works correctly. In this instance, the antibody’s sensitivity to virus is lost.
You might think that acidic drinks will result in a blank test. Denatured proteins, however, are very sticky. All those perfectly evolved interactions which would normally hold the proteins together are orphaned now and searching for something to attach to. The immobilised antibodies on the T-line are likely to stick directly to gold particles when they pass, causing the infamous cola-induced false-positive result.
Can you detect a false positive? When returned to a more favorable environment, antibodies (like many proteins) can refold and regain their function. I washed a test with buffer solution after it had been dripped in cola. Sure enough, the immobilised antibody at the T line regained its normal function, and released the particles of gold, revealing the real negative result.