Hong Kong News

Nonpartisan, Noncommercial, unconstrained.
Friday, Mar 29, 2024

How children are spoofing Covid-19 tests with soft drinks

How children are spoofing Covid-19 tests with soft drinks

Some children have found a devious method to get out of school – using cola to create false positive Covid tests. How does it work?

Children are always going to find cunning ways to bunk off school, and the latest trick is to fake a positive Covid-19 lateral flow test (LFT) using soft drinks. [Videos of the trick have been circulating on TikTok since December and a school in Liverpool, UK, recently wrote to parents to warn them about it.] So how are fruit juices, cola and devious kids fooling the tests, and is there a way to tell a fake positive result from a real one? I’ve tried to find out.

First, I thought it best to check the claims, so I cracked open bottles of cola and orange juice, then deposited a few drops directly onto LFTs. Sure enough, a few minutes later, two lines appeared on each test, supposedly indicating the presence of the virus that causes Covid-19.

It’s worth understanding how the tests work. If you open up an LFT device, you’ll find a strip of paper-like material, called nitrocellulose, and a small red pad, hidden under the plastic casing below the T-line. Absorbed on the red pad are antibodies that bind to the Covid-19 virus. They are also attached to gold nanoparticles (tiny particles of gold actually appear red), which allow us to see where the antibodies are on the device. When you do a test, you mix your sample with a liquid buffer solution, ensuring the sample stays at an optimum pH, before dripping it on the strip.

The fluid wicks up the nitrocellulose strip and picks up the gold and antibodies. The latter also bind to the virus, if present. Further up the strip, next to the T (for test), are more antibodies that bind the virus. But these antibodies are not free to move – they are stuck to the nitrocellulose. As the red smear of gold-labelled antibodies pass this second set of antibodies, these also grab hold of the virus. The virus is then bound to both sets of antibodies – leaving everything, including the gold, immobilised on a line next to the T on the device, indicating a positive test.

Gold antibodies that haven’t bound to the virus carry on up the strip where they meet a third set of antibodies, not designed to pick up Covid-19, stuck at the C (for control) line. These trap the remaining gold particles, without having to do so via the virus. This final line is used to indicate the test has worked.

The acidity of many soft drinks and fruit juices can lead to false positives in the Covid-19 lateral flow test but still be negative with a PCR test


So, how can a soft drink cause the appearance of a red T line? One possibility is that the drinks contain something that the antibodies recognise and bind to, just as they do to the virus. But this is rather unlikely. The reason antibodies are used in tests like these is that they are incredibly fussy about what they bind to. There’s all sorts of stuff in the snot and saliva collected by the swabs you take from the nose and mouth, and the antibodies totally ignore this mess of protein, other viruses and remains of your breakfast. So they aren’t going to react to the ingredients of a soft drink.

A much more likely explanation is that something in the drinks is affecting the function of the antibodies. A range of fluids, from fruit juice to cola, have been used to fool the tests, but they all have one thing in common – they are highly acidic. The citric acid in orange juice, phosphoric acid in cola and malic acid in apple juice give these beverages a pH between 2.5 and 4. These are pretty harsh conditions for antibodies, which have evolved to work largely within the bloodstream, with its almost neutral pH of about 7.4.

Even a small change to the chains can dramatically impact a protein’s function


Maintaining an ideal pH for the antibodies is key to the correct function of the test, and that’s the job of the liquid buffer solution that you mix your sample with, provided with the test. The critical role of the buffer is highlighted by the fact that if you mix cola with the buffer – as shown in this debunking of an Australian politician’s claim that mass testing is worthless – then the LFTs behave exactly as you’d expect: negative for Covid-19.

So without the buffer, the antibodies in the test are fully exposed to the acidic pH of the beverages. And this has a dramatic effect on their structure and function. Antibodies are proteins, which are comprised of amino acid building blocks, attached together to form long, linear chains. These chains fold up into very specific structures. Even a small change to the chains can dramatically impact a protein’s function. These structures are maintained by a network of many thousands of interactions between the various parts of the protein. For example, negatively charged parts of a protein will be attracted to positively charged areas.

Many schools in the UK have used regular lateral flow testing to check whether pupils might be carrying the Covid-19 virus


But in acidic conditions, the protein becomes increasingly positively charged. As a result, many of the interactions that hold the protein together are disrupted, the delicate structure of the protein is affected and it no longer functions correctly. In this case, the antibodies’ sensitivity to the virus is lost.

Given this, you might expect that the acidic drinks would result in completely blank tests. But denatured proteins are sticky beasts. All of those perfectly evolved interactions that would normally hold the protein together are now orphaned and looking for something to bind to. A likely explanation is that the immobilised antibodies at the T-line stick directly to the gold particles as they pass by, producing the notorious cola-induced false positive result.

Is there then a way to spot a fake positive test? The antibodies (like most proteins) are capable of refolding and regaining their function when they are returned to more favourable conditions. So I tried washing a test that had been dripped with cola with buffer solution, and sure enough the immobilised antibodies at the T-line regained normal function and released the gold particles, revealing the true negative result on the test.

Children, I applaud your ingenuity, but now that I’ve found a way to uncover your trickery I suggest you use your cunning to devise a set of experiments and test my hypothesis. Then we can publish your results in a peer-reviewed journal.

Newsletter

Related Articles

Hong Kong News
0:00
0:00
Close
It's always the people with the dirty hands pointing their fingers
Paper straws found to contain long-lasting and potentially toxic chemicals - study
FTX's Bankman-Fried headed for jail after judge revokes bail
Blackrock gets half a trillion dollar deal to rebuild Ukraine
Steve Jobs' Son Launches Venture Capital Firm With $200 Million For Cancer Treatments
Google reshuffles Assistant unit, lays off some staffers, to 'supercharge' products with A.I.
End of Viagra? FDA approved a gel against erectile dysfunction
UK sanctions Russians judges over dual British national Kara-Murza's trial
US restricts visa-free travel for Hungarian passport holders because of security concerns
America's First New Nuclear Reactor in Nearly Seven Years Begins Operations
Southeast Asia moves closer to economic unity with new regional payments system
Political leader from South Africa, Julius Malema, led violent racist chants at a massive rally on Saturday
Today Hunter Biden’s best friend and business associate, Devon Archer, testified that Joe Biden met in Georgetown with Russian Moscow Mayor's Wife Yelena Baturina who later paid Hunter Biden $3.5 million in so called “consulting fees”
'I am not your servant': IndiGo crew member, passenger get into row over airline meal
Singapore Carries Out First Execution of a Woman in Two Decades Amid Capital Punishment Debate
Spanish Citizenship Granted to Iranian chess player who removed hijab
US Senate Republican Mitch McConnell freezes up, leaves press conference
Speaker McCarthy says the United States House of Representatives is getting ready to impeach Joe Biden.
San Francisco car crash
This camera man is a genius
3D ad in front of Burj Khalifa
Next level gaming
BMW driver…
Google testing journalism AI. We are doing it already 2 years, and without Google biased propoganda and manipulated censorship
Unlike illegal imigrants coming by boats - US Citizens Will Need Visa To Travel To Europe in 2024
Musk announces Twitter name and logo change to X.com
The politician and the journalist lost control and started fighting on live broadcast.
The future of sports
Unveiling the Black Hole: The Mysterious Fate of EU's Aid to Ukraine
Farewell to a Music Titan: Tony Bennett, Renowned Jazz and Pop Vocalist, Passes Away at 96
Alarming Behavior Among Florida's Sharks Raises Concerns Over Possible Cocaine Exposure
Transgender Exclusion in Miss Italy Stirs Controversy Amidst Changing Global Beauty Pageant Landscape
Joe Biden admitted, in his own words, that he delivered what he promised in exchange for the $10 million bribe he received from the Ukraine Oil Company.
TikTok Takes On Spotify And Apple, Launches Own Music Service
Global Trend: Using Anti-Fake News Laws as Censorship Tools - A Deep Dive into Tunisia's Scenario
Arresting Putin During South African Visit Would Equate to War Declaration, Asserts President Ramaphosa
Hacktivist Collective Anonymous Launches 'Project Disclosure' to Unearth Information on UFOs and ETIs
Typo sends millions of US military emails to Russian ally Mali
Server Arrested For Theft After Refusing To Pay A Table's $100 Restaurant Bill When They Dined & Dashed
The Changing Face of Europe: How Mass Migration is Reshaping the Political Landscape
China Urges EU to Clarify Strategic Partnership Amid Trade Tensions
The Last Pour: Anchor Brewing, America's Pioneer Craft Brewer, Closes After 127 Years
Democracy not: EU's Digital Commissioner Considers Shutting Down Social Media Platforms Amid Social Unrest
Sarah Silverman and Renowned Authors Lodge Copyright Infringement Case Against OpenAI and Meta
Why Do Tech Executives Support Kennedy Jr.?
The New York Times Announces Closure of its Sports Section in Favor of The Athletic
BBC Anchor Huw Edwards Hospitalized Amid Child Sex Abuse Allegations, Family Confirms
Florida Attorney General requests Meta CEO's testimony on company's platforms' alleged facilitation of illicit activities
The Distorted Mirror of actual approval ratings: Examining the True Threat to Democracy Beyond the Persona of Putin
40,000 child slaves in Congo are forced to work in cobalt mines so we can drive electric cars.
×