How a lateral flow test strip works (kept simple)
ฝัง
- เผยแพร่เมื่อ 7 ก.ย. 2024
- I wondered how the lateral flow tests strips worked, so after doing a test with one I took it apart.
The deceptively simple interior hides quite complex molecular science. I'm not a molecular biologist, so I've kept the description of operation simple.
There are versions of these strips that can do multiple tests simultaneously, and also versions that are read optically to give a more analogue reading.
(The blood analysis uses the blood-plasma for the test.)
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
www.bigclive.co...
This also keeps the channel independent of TH-cam's advertising algorithms allowing it to be a bit more dangerous and naughty.
#ElectronicsCreators
Not sure if anyone else has said this, but the "C" doesn't stand for "confirmation", it actually stands for "Clive" - the test makers are big fans of the channel.
I thought it stands for control
@@ingolorenzo4158 Oh you sweet summer child.
Clive may not have Covid, but that test shows............Godzilla is pregnant. 😳
😆😂🤣
Yes, the 'C' stands for "Clive". The 'T' stands for "Teardown", because they know Clive will do a teardown on it. And the 'S' stands for "Schematic", because if there is anything in there that you could possibly draw a schematic for, they know Clive will do that too 👍
Cool, but what happens if you run mains current thru it?
This needs to be done as a FU to CVD.
Wrong channel, you want Electroboom for that :D
Much quicker results?
@@john_not_a_replicant this is definitely the right channel for putting 240V across something :)
AND if you do.....How will it taste...???
The second wicking pad at the end isn't incidental. It allows more volume of fluid to pass through the test. If it wasn't there capillary action would stop as soon as the fluid reached the end and much less fluid would act on the test areas.
That right there is engineering at it’s best - take something incredibly complex, and set it up so that anyone can use it. Genius, really.
incredible engineering, shame they are inaccaurate crap.
@@rich302uk They’re not particularly inaccurate - if done correctly, the accuracy rate is very high and the vast majority of people with a positive LFT have Covid (in fact there is now more concern about false negatives from PCRs than false positives from LFTs)
@@nemesis2264 you're exactly right, not sure what the other guy is talking about.
@@nemesis2264 That's like saying thermometers are useless because you saw a video where someone stuck one in a flame and it showed them having a 2000°C fever.
It's designed to give a result for mucus, how it reacts to anything else is irrelevant. It's not claiming to test whether your breakfast has covid.
@@nemesis2264 it tells you not to eat or drink before it for a reason.
"C" actually means "control" in the context of the "control" and 'test" samples in an experiment.
Y’know…I wonder how many people initially thought the C meant „Covid”, and started 💩ing themselves as soon as the line started to show up? 🤣
Makes me wonder why they use letters and not symbols on those. A small graphic of a Covid virus in place of the T and a Control flag symbol (See: Orienteering) in place of the C would avoid any misinterpretation of the letters! 👍🏽
Theres easier Lateral Flow Tests now too. My mum works at a school, she has to do these 2 times a week + 1 extra on the weekend for something else so I'm all to aware of how these are done since she asks me to submit the results to the NHS all the time on her behalf and check she's doing it right.
Thankfully her School provides her with the easier 15m ones, pretty much same as the 30m ones but you only swab your nose and its smaller, requires you to put in 4 drops, as well as having the liquid in the tube already (tube has a foil seal on it). It also requires you to mix it a bit more and use the tube to ring the swab out instead of just brushing the swab on the inner sides. She still has the 30m ones for the weekend tests she does extra too since its a requirement for a group hobby she does.
I'd be glad when it's not required for her to do tests anymore, it's kind of annoying to do 3 times a week.
both my kids do the nose test, provided by the school, twice a week. Lot's of snorting going on :)
@@FrancSchiphorst you're crazy allowing this. Do you know what's in these swabs? One of the components is ethylene oxide which is carcinogenic. The amount of utter ignorance on all of this covid scam beggars belief from masks to vaccines to the fraud of the PCR test.
@@paul756uk2 LOL
@@FrancSchiphorst nothing lol about it pal. Do some research instead of burying your head in the sand. There's no way any child of mine would have one of those stuck up their noses. There's also a very delicate membrane between the nose and the brain which can cause brain damage if the swab is pushed up too far. They're giving the tasks of doing this and jabbing to totally unqualified people. It's no joke. It's sad and unfortunate that most if the population have absolutely no idea of what's going on.
@@paul756uk2 still LOL
For the curious: in the most common rapid test in the US (BinaxNOW), the test comes as a foldable card. One side has a small well, and the other has the test strip. You drop the clean carrier fluid into a well on the test card first, then swab your nose, then wedge the swab into the test so its tip is sitting in the well. You spin the swab a few times so it's well mixed with the carrier solution. Then you fold the card over so the wick is sandwiched against the soaked swab. The fluid flows through and you read the markers through a window on the outside of the card. Same basic technology, just a different way of doing it.
Captain Fwiffo?!
Thanks that's interesting. Do you get your tests for free? I know medical costs are an issue over there so it was nice to see the vaccine being given out free.
@@Chenty91 Tests are provided by the state or employers where they're needed for the job. Some local governments administer some PCR tests for free. Otherwise we buy the assay tests ourselves; they're about 12 dollars at local drugstores.
C = Control. This is the manufacturers self test that ensures that the contents of the kit are working properly. How do I know? I'm a Lab guy. 30 years of working in labs in the US its MT(ASCP) or CLS(ASCP) by designation.
It was "a Lab guy" that released Covid into the world... Hmmmm, so it was you.
Pregnancy tests (at least the 2line versions) use the same concept. One line is the control, and indicates that the test worked. The other (“2 lines”) is the actual result.
@@orac229 good one! Funny joke... LOL
You need to be a lab guy to know this. It's not rocket science.
@@hamaneenee your comment reminds me of that Mitchell & Webb sketch when a rocket scientist and brain surgeon meet.
Excellent explanation for the masses! Worked in a medical test kit company (actually purifying the antibodies from goat serum), and this is a good explanation.
P.S., the membrane is usually made from PVDF or nitrocellulose. Or similar.
Nitrocellulose ? Isn't that otherwise known as Gun Cotton ? Is it wise to tell Clive that he might have something explosive there ? 😉
@@JAJAJA99999 purifying antibodies from it.
Edit: Goats are one of many animals that are used for antibody test kit generation. Goats, sheep, donkey, rabbit, mouse, even chicken are all used. The chicken antibodies are usually purified from egg yolks (100% serious).
It doesn't go up like flashpaper.
@@BigClive Ha, ha ha! Brilliant! I knew you wouldn't be able to resist! Keep it up, big fella!
@@Newlife-ol6pk I don't know about *this* test, but in general terms you produce a pure protein that you want to detect. In this case, probably a protein on the surface of the virus. The protein is then prepared for injection into the donor animal, just like a vaccine. The animals are injected and this elicits an antibody response. Then, you take the same protein and immobilize it on chromatography resin, and use that to pull out the specific antibodies you want. So, while there will always be some cross reactivity, you can have a relatively specific antibody for your test strips.
Can confirm as a science teacher, we do still do chromatography experiments using filter paper and ink!
Who stole Mr Smiths apple and left this note!
***lightbulb pings on*** I suddenly get why they're called a "lateral flow" test now!
Lightbulb moment 💎
What an amazing design! Have been wondering how these worked, thanks Clive.
Thanks Clive.
It's very impressive but I think it's about time somebody developed a non-invasive test that is about as cheap as this and just as accurate. Either that or a suitable blood test (that's 'invasive' of course but a pinprick is far more pleasant than ramming a swab up your nose or down your throat).
It's not that amazing, it only works 40ish % of the time.
They don't work ! It was invented in 1984 ! It does NOTHING to test Covid !!!
@@chompchompnomnom4256 This 40% claim was from the earliest study that is not even cited anymore. More recent research finds accuracy of LFT tests to be above 80% in symptomatic cases and 90-95% at the peak of infection. Less sensitive to asymptomatic cases.
I've done so many of these my gag reflex has improved considerably. My husband however has the biggest most dramatic strop to to the throat swab and then with the nasal swipe he just clenches up on my wrist (he, as a veterinary nurse cannot do it himself) and sneezes several times. Weirdly in other situations he has no gag reflex but that tiny swab, far too much.
I do love the quick simplicity of them, they became a part of life and I don't mind as it really is a quick, simple test.
Also, welcome to the 2021 cold club, I've not had one for 4 years and had it for 4 days this year. Isolation really did ruin our day to day defence systems. I was not used to being ill and man did that suck being ill with a simple thing like a cold again, forgot how crap they are.
I recently visited my dad and in his 60s now, he has really embraced the home testing scene. He has no major health issues but like to test his blood sugar, cholesterol and check his blood pressure on a weekly basis. The other day he was desperate to show me his blood sugar kit and wanted to test me. I hated the idea of that thing that pricks your finger so much and ended up making a right fuss about using it. My dad was taking the mick out of me for being a wuss. Fast-forward to my dad needing to travel recently and take a LFT for the first time. He's totally dancing around and making stupid noises as he swabs himself. Way worse than me with the pricker or lance or whatever it's called! I had to give him some grief in return for that.
@@WadeWomersley I’ve got one now and it’s floored me. I’ve done a stack of COVID tests and they’re all negative do it’s not that. Everyone else in the house has had it and they felt like shit for days.
Don’t have to worry about the gagging now, for the last couple of months NHS England (so this does depend where you are) have been sending out nose only tests that also have a shorter 15m development time …
I just got my first set of the new ones - they’re so much easier! Pre-filled vial, only the nose swab required, and 15 minutes to result - amazing improvement.
Im a pharmacy tech and we do the NAAT tests. Id love to see the inside of that machine but those things are really expensive.
For what I've read it does pretty much the same thing. It heats up a chemical that breaks apart everything but the smallest stuff and it filters thru sand-like stuff. Then a special bead of some metal (maybe an alloy) sticks to just the target virus. We have kits for Covid, Flu, and Strep, so it must be a different metal for each. So neat.
th-cam.com/users/mikeselectricstuffvideos
he does those type of teardowns worth a look over there
You are the first to refer to it as NAAT, thank you for giving me hope in the worle XD
Hi Clive bit of a heads up for your viewers, on the blue box's check the use by date as some are close to being out of date and if you use them they can give a false reading .... also a date can be found on the sachet holding the plastic test strip ..
@@walterbishop1697 but wouldn't putting beer or lemon into the test invalidate any test results? Don't do that if you're trying to use it to test for covid.
@@walterbishop1697 If it test positive after drinking beer or lemon juice, then I would be worried.
Also (personally) I recommend trying to get the FlowFlex ones instead of the NHS Test & Trace branded ones. Some local authorities give them out, or you can get them by collection/delivery (seemingly dependant on location).
About a month ago younger brother caught Covid (likely from his school), and first tested positive on a FlowFlex test. He chose to do one daily after one of his classmates tested positive. He repeated on one of the school-provided NHS T&T tests, and it read negative. Repeating FF, he tested positive again. He was worried about false readings, and repeated for each over the course of the day, eventually testing positive on 3 FF tests and negative on 3 NHS T&T tests, then a day later testing positive on a PCR test.
I presume the FlowFlex tests are more sensitive, as both were well in date (until 2023), and were both performed exactly to the instructions.
@@walterbishop1697 "There can't be positive cases if they're never tested!"
Now this is some 4D Chess level Covid prevention.
@@walterbishop1697 they are not supposed to test acids like lemon juice, it is silly to try that.
I got one of these tests a week or two ago. The lady at the pharmacy asked me if I wanted saliva or blood based test, and I went for the latter, because of the pharmacist's recommendation.
Test is pretty much the same, but obviously different a bit, because of the different sample being collected. They give you an alcohol-soaked cleaning pad to clean your fingertip, a spring loaded lancet to sting yourself, a plastic pipette to get the blood from your fingertip and place it onto the test, and some liquid to put two drops of onto the test area after the blood. Apart from the control strip, there were two strips labeled IgG and IgM and if any of these two appearing would indicate a positive test result.
I had to go to a dedicated testing site to get tested. The day I got there, I was just getting over a cold, and when they went through my nose to swab it made my eyes water and the junk in my sinuses clear. I'm not sure what it is about the swab, but I hadn't breathed that clearly in well over a week. Even better than a netti pot!
Lol!
Roto Rooter... Roto Rooter...
I need one!
And it showed you had a Coronavirus! That's it. Because Colds are ALSO Coronaviruses. As are influenzas.
So it DOES NOT DIFFERENTIATE. You need a virological BLOOD TEST to do that.
So, if you have even a normal Cold when ylu have a test (as you had), it will react.
But, because Covid -19 is all the rage, THAT'S what you got! Why do you think that, in 2020, there were 0% influenza figures??
@@chrismaguire3667 actually, it came back negative, sooo...... Yeah...
Thanks Clive, had wondered what those 'lateral flow' tests the UK media kept on talking about were. Now I know that's just the 'quick tests' as we call them on the continent.
Is there anything that you can't disassemble and give us a detailed explanation of how it works? You always do a great job to get the point across in your videos. Thanks
The female of the species. 😂🤣😂
Nukes
Clive? Haha Hell no!
Get him a tesla we can have a series longer than lotr
@@coolbrotherj I guarantee if he could get his hands on it he would be able to go into detail about how it works. The hardest part about nukes is getting the materials to make them.
I think the 'C' might stand for "Control" instead of "confirmation", but I could be mistaken
It probably is.
'C' stands for Clive, Big Clive, of course!! :-D
S is for sample, T is for test, and yes C is for control
@@BigClive The booklet says control line region, they work in a similar manner to the pregnancy tests sold in poundland and other higher priced shops.
@@paulroberts01 They actually work in the exact same way, you just use different antibodies for the lines and conjugate (or "molecular keys attached to dye.")
As someone who has never had a "test", it baffles me that so many people talk about shoving swabs up their nose/down their throat regularly like its perfectly normal. Still, it is fascinating to see how they work.
It baffles me that some people can still have their head this far into the sand.
@@TheFool2cool Really? I've never had a test either. Single, retired and basically don't go out. Fully vaccinated, never had any symptoms, never had any of the few people I interact with warn me that they might have exposed me - why would I need to be tested?
@@FurrBeard Yeah well not everyone can sit at home and do nothing. my whole family has to work, my kids have lot's of contact with people and the test weekly.
No symptoms doesn't mean not infected. i got infected (no jabs for my age at that time) and didn't even know it. it was my daughter who told me to get tested because she had direct contact with an infected person. but it was a collegue who actually got me infected. So tell me why wouldn't i get tested it takes 15 minutes.
@@drood78 Furr Bear is simply saying that they don't feel they would need to be tested. Nothing to do with you so go and get tested as many times as you want because nobody cares.
Let's put a dual-core 32 bit microcontroller, a fancy optical light guide, LEDs, optical sensors and a lithium button cell into this one-time use disposable test unit - and you have created a lot of electronics waste and the item which TheSignalPath took apart this summer.
I would prefer Clive's non-overkill version...
"Even though I am vaccinated"
You can catch COVID while vaccinated btw, and it still hits you hard. It just less lethal
Totally. I have a friend who is fully vaccinated and is very careful where he goes, but caught Covid last week and is stuck in bed with what feels like a bad case of flu. I'm just glad he was vaccinated because otherwise he would probably have been seriously ill. I've had the first two jabs and am lined up for my booster in a few weeks.
@@rpdom But you have no way of knowing that at all. Family of 4 all had Covid (no one jabbed), kids recovered after ONE DAY and both adults were no worse than double jabbed friends. Swine flu felt 100% worse TBH! What's the long term plan with these vaccines? New jab every 6-12 months? Totally impractical. The pharma companies are laughing all the way to the bank (& the research in many cases was funded by the TAX PAYER)
The vaccine is not designed to keep you from getting infected. None are.
It's designed for your body to recognize and gear up for when it encounters the virus "in the wild" and limit disease (think "DIS-Ease"). Because your body can now recognize the virus for the threat that it is, when you get it, your body can go right on after it immediately.
It's like studying up for an exam at school. Once you have hit the books, when exam day comes, you can hammer through it in no time. You might not ace the test (you might still have some symptoms), but you'll be in and out in no time.
Some bodies walk into an exam without studying... and odds actually are they will do okay. But there is a percentage of people that this "exam" out and out kills. That's the problematic part that scared the medical profession.
At least initially, there was little the doctors could do but watch, but there are a lot of tricks to helping patients survive now.
Still, it's quite a gamble in my opinion to walk into an exam without studying for it - especially when "study" takes longer to get to and from, than it does to actually get the jab.
@@hoojchoons2258 I did say "probably". I can't be certain the vaccine saved them, but in general many tests from different places have concluded that the vaccine is very likely to reduce the effects of Covid at least. There will always be cases where it doesn't, but I'd rather not take the chance.
@@hoojchoons2258 go spew your consipracy shit somewhere else. i already know you're lying. mRNA is in development for decades.
> I'm not a molecular biologist, so I've kept the description of operation simple.
I'm neither, and I find the description good enough to make it "it ain't magicks aye!" - which we do need. Thanks Clive!
That’s nice, but what happens when you carbonate the serum with a Sodastream first?
Simple in the sense that you probably need a few Nobel prizes to understand how the biochemistry works... but yeap...looks like that felt tip pen, acetone and blotter paper stuff from school. Very clever! Thx for the teardown.
Thank you for disseminating this information. You are truly a boon to humanity Clive :)
Misinformation, he's a traitor to humanity.
The latest ones are nostrils only.
The liquid is also already sealed in the test tube.
Tricky to get hold of in the UK - I was told by 119 operator that you can use the throat/nasal test kits and just do the nose swab. This is the internet don't take my word for it! Ring 119 or ask your chemist etc.
Had one last week (UK), nose only. Still wondering as to how accurate these are...
My kids have had several version and some have liquid in the tube, some use the system in this video. Just depends on the brand.
@@skysurferuk 20% false negative rate, 0.01% false positive rate, if done correctly.
hi all,
just think yourselves lucky there is a small group of the population that have had the pleasure of doing those tests every two days :), oh what fun that is.
best regards
Simon
Two a week for me. Just had a false positive too which has screwed my short break royally.
🙄
These are the older kits that were replaced by slightly different test kits a few months back. A few small improvements were made - the buffer liquid is now already in the dropper with a foil seal on top, you only have to swab your nostrils now so no tonsil swab, and the tests only take 15 minutes instead of 30.
That sounds like the FlowFlex tests, and I don’t think they’ve completely *replaced* the (NHS) Xiamen Biotime ones - I’ve been issued two FlowFlex kits, then more Xiamen ones after that.
Personally I think I prefer the Xiamen ones. The nasal-only FlowFlex swab seems like an improvement, but doesn’t work so well (And probably won’t give as accurate a reading) for those of us who have trouble with ever-blocked noses! 😇
I was (wondering) and now I know! 😁
Taking them quite regularly.
You wouldn't have thought he'd be a bewildered soul.
Ah, I've done more than enough lateral flow tests in my life and most of them were MRSA tests (after hospital stays as we now live with MRSA) and 2 for the Hokey-Cokey (
I did the antibody test too and they didn't warn us that the so called "needle" was basically a stanley knife blade on a spring. I remember thinking "they better not lose this because I am NOT doing that again".
The lateral covid tests are the easy ones. The medial and vertical ones though? Oof. What a nightmare. Slaynt vie!
"it's very intrusive" 😂😂😂😂 one way of putting it haha
I used to work on the production line as a QA making these , you'd be very shocked on the low hygiene standards in the "clean room"
Glad there are test options other than PCR which can effectively be done at home. So cool.
Amazingly simple but yet so advanced! Glad we have science to come up with sollutions like these.
Enjoy science while it lasts, some people are trying to legislate against it.
It took me so long to realise that "lateral flow test" was because the specimen flows laterally through the test strip, instead of it being like a small strip you dunk in the solution.
You actually showed using the test BETTER than the muppets i have seen using them that have been trained in their use.
Good job.
That has got to rate as one of the best "public information" videos since their inception...very appreciated and shared.The versions that were sent out if requested via .Gov had to be returned for test results BUT could only be posted in certain Royal Mail post boxes...I live in central London,ie by Waterloo Station and there are loads of post boxes but the nearest one acceptable for returned LFT's was 1.3 miles from my home address...and as someone with mobility issues that was an issue. Also the cotton bud,after taking the throat and nasal sample had to be snapped before being locked in the phial. The indentation indicating where it should be snapped left it too long to get into the phial...a text let you know the results...LOTS of piss balling around...liked the usability of the test you had a lot more...as ever Clive best wishes from South East London lalala
Technically you could've used any post box as long as it was still to be collected that same day - the "Priority Postboxes" are simply post boxes that are part of a later collection route and the rest of the post boxes are collected by the Posties while doing their delivery, so collections could be made from those any time after 9am depending on area.
@@_Steven_S Hey thanks for getting back...nonetheless it was a pain...I went into the main post office in Walworth Rd really expecting to be able to dispatch it there...no way, another half mile down the road to the post box outside Marks"n"Sparks!!! 👍"s up ⚠️
Great timing - I took one yesterday that was positive (as was the follow up PCR)!
I took one of these when my symptoms started Wednesday and again today after receiving a positive PCR this morning from a test on Sunday and neither indicated.
Various styles now, I'm getting quite a collection of the shells because we take several tests a week for work, care home visits, fun (?), etc. Must be a re-use for these, along with my ever growing HDPE milk carton top collection.
Tip, they’re still very effective just up your nose, 10 seconds up each nostril. Confirmed with PCR test. I can’t stuck one in my throat without throwing up!
The newer ones don't even ask you to swab your throat, just your nose, and they complete in 15m not 30m
I am just taking those PCR Test. I think the straw they use to poke nostril is the worse, I'm trying hard not to sneeze because suddenly my nose throw out a bunch of liquid 😂 and I don't even know what those one made of, because I didn't see any cotton around it unlike the one they use to swab throat, and the point shape had many bulging part that make it even more triggering to sneeze out.
And just swabbing up the nose is permitted for those with a sensitive gag reflex 👍
It's not been well communicated but is in the guidelines. Everyone seems to think it has to be throat and nose, but nose only is also acceptable. 👍
I have a couple of blood typing test kits that use this lateral flow technique to perform their function.
"YOO-reen." Clive takes the piss out of it!
In the last week I have done several lateral flow tests and two PCR tests.
I have remained steadfastly negative despite my teenage daughter and then my wife catching the dreaded lurgy.
I figure that being a travelling technician and having not really stopped going out throughout the pandemic due to the key/essential nature of my work, I have maybe developed a better immunity than many ... as well as being vaccinated of course.
In the meantime, it's the spare bedroom for me, just in case.
Quite possibly you've built up natural immunity 👍 The 'super cold' that's doing the rounds now is quite likely to be a result of so many of us staying isolated and not being in day-to-day contact with others' germs so our immune systems were slightly unprepared.
The idea of natural immunity seems to have been shunted aside lately but it does exist and nature understands it - mothers pass on antibodies through their breast milk!
I did learn how to do plate chromatography in high school chemistry as well (graduated in 2013 in France)
We even did it in primary school on filter paper and with felt pens - the teacher wanted to show us that a plain color in a felt pen is made up of a lot of different dyes.
In order to do this experiment you take a piece of filter paper, draw with the pen on the paper and then let a drop of water wick from one side through the color markings.
I actually am a biomedical scientist, or hospital lab tech if you prefer. What you are actually doing is looking for pathogens in all the right places.
To the tune of "sticking that thing into your nose and then rubbing the tip against the bits of your airway that is bordering the lower parts of the brain".
The rationale here being that this area is normally kept scrupulously clean of microorganisms by your immune system, so if any pathogen is currently infesting your respiratory system, this is the place where it would be reenacting the Normandy invasions. If you do this correctly while perfectly healthy, it's uncomfortable as all hell, if you do it while even remotely sick there's about 75% odds the swab is going to be covered in blood when it comes out.
"if you do it while even remotely sick there's about 75% odds the swab is going to be covered in blood" specifically with Covid or is that the case for many other corona viruses or even other illnesses in general? Sorry for the question in laymen's terms.
@@Stigstigster It's the case when any nasty virus or bacteria manages to push far enough into no man's land to show up in this area. It has more to do with the fact that there's an inflammation going on where there should be none than what kind of pathogen is involved.
@@Reddotzebra Understood. Thank you.
Glad you're not infected. Also glad that you're this curious and explanatory. ;D
IT'S A JOKE at best !
@@gertjanvandermeij4265 what exactly is a joke?
If you think that makes you gag, then try gastroscopy without a sedative. That one was an experience I don't want to repeat (although doing it without a sedative did mean I could drive myself home).
nb. chromatography works on an entirely different principle and it is very much still in use.
There is no way I'm sticking a swab down my throat (I've no tonsils to swab anyway) then up my nose (sneezing snot all over the place), thank you!!
I sometimes think that the jokers who come up with these tests have a warped sense of humour!
I have an Idea you could do a video on. A reverse engineering of the Tassimo single serve coffee pod system.
I have to say, rather than "am I infected?" Tests, we need some thing like this which can detect relevant "T" and "B" cells long after vaccination and/ or infection.
Assuming this is like SARS (now SARS1) where tests have indicated persistence of T-cells and therefore a robust defence, 17 years and counting after the outbreak, such a test would give a true indication of both the percentage of infection, and likely ongoing immunity (due to all causes) in a population.
Current advertised tests are so cosy and labour intensive as to be impractical for mass distribution.
i recognise your name? Do you comment on the TWiV channel? i am a regular, well i never miss a live broadcast and doing the courses with vincent
Hope your cold is better. I like that you chose to post this in the same week that I used one... Only mine had two lines.
In that case you need to retest?
@@rogerstarkey5390 technically yeah. You can get a false positive with the lateral flow tests so I also had a PCR one.
@@D-S-9 And are you well? I hope so and I wish you all the best.
@@Stigstigster wow, thanks for asking. Clive has the best community. I'm doing better than a lot of people, but it really is kicking my backside. And to top it all off, I can't smell my whisky!
I do one of these twice a week. Nice to see them get the Big Clive treatment!
The film "Idiocracy" ... Has now become a reality.
I like when people use simple tap water or even soft drinks on this things. Very interesting method when used properly to detect specific molecules but not as accurate as they "sell" it for TV race.
Thank you again.As we have come to appreciate . A concise in-depth explanation of the inner workings of new tech we may come across.
I was under the weather in September with a bout of influenza-like symptoms, so I decided to get an anti-body test when I recovered. Turned out my unpleasant, but hardly life-threatening flu was in fact the dreaded variety that Google does not want you to mention. Natural immunity for the win!
Unless you have some other health problem, it's extremely unlikely to kill you or even make you particularly sick. For this purpose, just being old counts as a health problem.
About the end of April 2020 I came down with a mightily nasty bought, fever, chills, muscle aches, tiredness, the lot. It was rather scary the first night, as I'd never had real chills before. At times I wash shivering so hard I couldn't operate my hands in any useful way. I was noticeably sick for four days, then rather irritated and bored for another 10 while I waited out my quarantine.
Though natural immunity is actually considerably less effective than the vaccines at preventing re-infections, so best get vaccinated. It’s effects are unpredictable, but one thing that is consistently true across all ages is that it is considerably more likely to kill you or put you in hospital than the completely different influenza virus (at least the common circulating strains).
@@Zveebo Mortality rates for the disease in question (mustn't upset Google's algorithm) are on par with other SARS-like influenzas at 0.01%.
Mammals have relied on natural immunity for millions of years, and in this case I am more inclined to rely on that than on a rushed, half-tested concoction from big pharma.
@@kimvibk9242 Honestly, you have every right to not get the so called vaccine. The government and media have clearly succeeded in dividing people and making the people who did as they were told and got the so called vaccine to turn against anyone that is a critical thinker and made their own mind up about it.
Big Clive and Nile Red Collab where you harvest the gold from these?
There would only be a molecular level.
Yeah,BigClive, That never stopped NileRed before....
I was expecting a connection to the house mains and flickering lights.
Or swelling, steaming hot dogs.
I was disappointed there was no capacitive dropper.
I followed the NHS video for staff which does not use the back of the throat bit, just both nostrils 10 turns each. Makes me sneeze a lot but no gaging. Other half has worked her butt off though all the lockdowns and still works bloody hard.
I wouldn't do one.
@@JamesSmith-vz8yr good for you…?
@@ARSZLB Noser4p3 Zach.....
Brilliant explanation, they should definitely be left for the full passage of time and be sure to allow your juices to ferment in the liquid for best results.
It's actually specified that you DON'T leave them too long.
20 minutes for the "double swab", 15 minutes for the "nasal only"
Ooor, you can always read the Manuel for the individual/respective manufacturer and do as they are designed to be used 👍
@@IcecalGamer I tried reading the Manuel, but he became upset from the unwanted attention.
@@rogerstarkey5390 The full passage of time then? (sorry, i am remiss. "As recommended by the manufacturers instructions")
@@stuartliddle7228 Thank you for taking my setup 🤣
My own story is that i am part of house hold where two people tested positive PCR tests and I tested negative.
So I took lateral assay through out the week every day to make sure I wasn't infected. Come this Saturday as part of the Welsh rules I had to have have another PCR test to which I tested positive.
That Saturday I tested my self with a lateral assay test which came back positive. The night before it came back negative.
So although these lateral assey tests are great you must remember unless your producing a enough viral load you will get false negatives. However if you get a positive result it's very likely true because they rare give out false positives.
So what your saying is if I save all my tests and collect everyone else's, I can melt them down to get a gold bar and become rich?
We're talking nanoparticles, you'd need millions of tests and then you'd have a shit ton of waste to dispose of.
@@tncorgi92 I know, I'm just being silly
The amount of gold is absolutely microscopic. Literally just molecules.
@@tncorgi92wouldn't be all the same plastic type, and just paper, the gold recovery would be recovered, by burning with acid or just fire, in a Kilns the paper part, and separating the mesoscopic gold/paper/ash soup/added to some-sort of acid and collect what floats or sinks, and repeat, that should be gold dust, in amounts, worth melting down to a small gold bar, if, (as an example jewellery workshops collect all there dust for recycling, looking for looking little parts or gold or silver, in the dust) so there is a system, already setup, to recover micro sized gold dust)
Hey ya Clive. Just stopping in to say hi and how much I appreciate you and your channel. 🤎🧡🖤🤍
You should checkout the electronic covid tests kits, the electronics are totally unnecessary, but possibly hackable? the ones I've head of use a 32bit mcu
Lemme guess, they're the same thing as those "digital" pregnancy tests that are just a standard one but with a light sensor on the testing bit?
@@kiefac Yep. It was SignalPath that did the tear down.
I’ve used one of those, from a company named Ellume. The actual test components are very similar to any other lateral-flow test strip, except that the antibodies are tagged with fluorescent dyes; the PC board includes a couple of UV LEDs and some photosensors, and a ridiculous unnecessary apparatus that allows the device to send the results to your phone via Bluetooth. Silly thing was MUCH harder to use than a simple strip.
Apparently you can play Doom on those.
@@fluffycritter But what can you do with the mysterious microchips Bill Gates has hidden in the vaccines? There must be millions of them floating about waiting for some ingenious hacker to repurpose them! :-)
my kids' school just sent these home. thanks for the information. greetings from nova scotia.
We have something similar in beekeeping for testing for American foulbood a bacteria infection that kills bees. Thank you for showing how they work
How on Earth do you get the stick up the bees nose?! 😮😂
@@Pugjamin very slowly
@@Pugjamin no the pupa turns into goo and you add the samples to a bottle with some steel shot to mix it up then drip it on the test strip
The fact that these types of lateral flow tests are so common is why S Korea had so much COVID testing so fast. It isn't the most reliable thing, but cheap and easy.
It's been a long, long time since I've kept bees. It's great that there's a test for AFB now. Is there also a treatment?
Back in the dark ages (1980s) we had to go by our sense of smell. Infected pupae smell like glue. If we found it, our only recourse was to cyanide the bees and burn the affected hives. Nasty disease.
I googled about covid test in feces. And one manufacturer stated that their test could be done in throat, nasal and feces.
You need to sample from 6 places around the stool
It seemed like it was just an ordinary rapid test. In Norway I got some ordinary Siemens rapid test. If I get a positive nasal test for covid-19 I will try it on my feces also.
My siemens has a filter on the top part of the droplet sample tube.
Don't take anything from a company that has no liability for its own products.
Clive, just to note, there are two types of kit now, the latest version doesn’t require a throat swap.
Correct - You can use a papaya, a goat or engine oil, and it still produces a positive result.
I don't know about a goat or engine oil, or even a papaya, but I do know that acid reacts with the antibodies in the strip and causes a positive result - it is due to the way that the test works, so a lemon will produce a positive result.
Well, if you gag, at least you know you've gotten the swab to the right part of the throat.
I think we're looking at two different effect: The pad wicking the solution along is a form of chromatography, which separates out the contents by various physical properties. The visible binding keys are probably anti-body based, as they are in the similar pregnancy tests. Being able to cheaply make monoclonal antibodies in industrial quantities ha been one of the greatest benefits biology has given us in the last 70 years.
Here in Canada, I didn't do any sort of chromatography until a couple of courses in university. The first time was paper chromatography in organic chemistry lab, where we weren't separating sugars for identification (we had pure sugars and were putting only one in each track) but we had to explain why different sugars moved different distances. (The short version is that different sugars interact with the substrate and the carrier solvent differently, based on the number and arrangement of hydroxyl groups and and other groups on the molecule.) The other was an upper year genetics lab, when we used it for DNA sequencing, which is done with a gel electrphoresis form of chromatography and some incredibly nasty chemicals that will kill you horribly if you get contaminated with them. (I was almost killed by a completely different part of the course, where we did basic genetic engineering of bacteria. This exposed me to bacteria with multiple antibiotic resistance genes, which became no END of fun when I developed severe bronchitis later in the semester. I forgot to tell my doctor about that exposure until the second round of antibiotics failed to kill off the infection. Then, he put me on Ciprofloxacin, the go-to antibiotic for that kind of problem and it cleared the infection just fine. Rough on the gut, but there's ways to mitigate that. Good thing I like yogurt and don't mind live culture ones.)
I've got some dextrose, glucose, and sucrose. Now I want to see what they look like on blotting paper and see if I can tell a difference after developing. Thanks for the idea to keep me 'not bored' on a Monday evening.
The latest lateral flow tests my local area, Suffolk, are giving out tests that only need a nose swab, no gagging with scraping the back of the mouth.
I've had that cold, it laid me low for a week. Horrible thing, I'm still coughing a bit 2 weeks later
It’s not a cold
Maybe it's a toomah.
I been having small coughing fits the last 18 months now lol. Its hard to tell if it's covid or asbestos caught up with me
@@qwaszx2 lol colds are caused by rhinovirus’, COVID19 is caused by a virus in the family Corona, literally an entirely different thing.
If you’re going to have such a strong opinion at least bother to do the bare minimum and check you know what you’re talking about.
@@qwaszx2 all common colds are caused by rhinovirus’ by definition. I’m not confusing influenza with common colds at all. Also COVID 19 is the name of the disease not the virus. The symptoms of this Corona virus may be mild, moderate or severe but never a common cold because again, common colds are caused by rhinovirus’
In Germany we have mostly tests that only need a swap from the first part of the nose, so only 2-3 cm or so into the nose. 15 minutes later you have the results.
Also for kindergarten we get free lolly tests two times a week. A bigger swap which you only swap in the mouth to collect saliva. Works way better for small kids.
We have those (Flowflex) in the UK now too.
@@xRepoUKx Was going to say that the description seemed like one of those Flowflex ones I used a few days ago here for the first time. Its swab pokey bit didn't expect to be nearly as far in the nose as the one shown here. And compared to the procedure described here I can really appreciate that the fluid was pre-filled, only had to tear off the seal and insert sample, then many of the same steps including putting the dropper lid on it.
Only vaguely heard of the lolly ones before, I can definitely see the benefits in that with young children that are often already moving their head out of the way or protesting when they see the wet washing mitt approaching after dinner before they are allowed to leave the table. Not sure how well small swabs going into the mouth and/or nose will go down with them.
Finally: COVID-19 ASMR.
Thank you, my friend! Stay safe and well. 👍
I find the eye on side of the tested nostril just tears up, after having done them multiple days in a row. The sneezing is easy enough to suppress but a couple times I nearly sneezed violently on a nurse.
The ones here only need sticking the swab in for 2.5 centimeters and twisting it 5 times against the middle plate of the nose. It is fairly okay if doing it yourself.
Interesting, just read a book about the Covid tests. The swab has to be nylon, not cotton. One company in Italy was the biggest producer, so big problem early on.
I absolutely hate doing the swab bit, I’ve done 4 or 5 of those tests. I don’t mind doing it though, I think it’s incredibly cool that we have them and the vaccines and all the rest.
I had to do one and I damn nearly threw up when trying to get at the tonsil area. Highly unpleasant to do. I do agree that it is really cool that we can use such a simple test for so many applications though.
I am both surprised and happy. After seeing the title and watching the video I though to my self that the comments would be awash with remarks from certain individuals who think that COVID is a Government lie. Surprised, there isn't. I'm happy that the quality of viewer of Big C is of a high standard.
Also that those 'molecular keys' are specific enough that they can tell SARS-CoV-2 from other 'common cold' virus - even in mixed company
coronaviruses are not similar to the "common cold" so... probably, yes.
@@ryanjcole From WIki (for simple ref point) 'common cold' : "The most commonly implicated is a rhinovirus (30-80%), a type of picornavirus with 99 known serotypes. Other commonly implicated viruses include human coronaviruses (≈ 15%), influenza viruses (10-15%), adenoviruses (5%), human respiratory syncytial virus (RSV), enteroviruses ... " While I did not intend to do a tutorial.. because the SARS-CoV-2 is a Human Created Frankenstein virus with at least five animal GoF addons , my point is that there is a soup of general virus family of 'common cold'. I have no idea which of the GoF or natural attachment points they used for the SARS-CoV-2 test.
@@goofybrained6929 "Human Created Frankenstein virus" Please expand!
@@goofybrained6929 Going to go out on a limb and say the spike proteins since those seem to be pretty conserved. Then again I have not actually confirmed this so take it with a grain of salt.
Perfect timing! Me and the Wife each took one of these quick tests today as many at work are catching the "C"...The results say we both won a 14 day vacation in our home and only our home...Stay safe out there everyone, this is not much fun.
Would you like me to send you a strip that I use to test my INR readings at home? They're quite sophisticated.
Very interesting. I've had a number of RT-PCR tests, but I've only had one what they called a rapid antigen test, which I believe is a lateral flow test.
There was a positive covid case at our other office, so the people on the same level had to get tested and quarantine for 2 weeks, however since we're considered an essential service the people on the other levels only had to quarantine for 3 days as long as they got a negative PCR test, then get LFT tested daily (work days) for the next 2 weeks. But because they moved some of those people to our office, they had to set up a testing station there for them to get tested. And on the last day of the 2 weeks, everyone else on site had to return a negative LFT test to certify the workplace covid-free.
But the silly part is that they basically they had to pay for an ambulance and two healthcare workers to sit around in our carpark all day, every day for two weeks just to do the testing. They wasted an entire ambulance and two healthcare workers for 2 weeks during the peak of the pandemic, when the tests are so simple anyone can do them. Boggles the mind.
Thankfully I've been lucky. Been going in to the office full time since basically the end of our first lockdown in July 2020, catching public transport and everything, and haven't had so much as a cold, let alone tested positive for covid. It's surprising how less frequently you get sick when basically everyone's forced to wear a mask 24x7.
The ambulance and presumably associated qualified staff for it might have been a bit overkill imo. But in that situation I wouldn't say that "so simple anyone can do them", you'd want a decent sample to be collected and if you take random people to do it or have people do it to themself it could lead to inadequate test results that don't represent the actual situation.
There was definitely room for a better option if you'd ask me, don't know where, when and in what climate it was. But it shouldn't be too hard to instead have a tent or maybe one of those portable things seen near work sites if a tent isn't suitable. Then the public health organisation of the area just needs to have sufficient people that got a bit of basic training that know how to collect the sample and process it. Might require a few qualified healtcare workers initially to train them, but it's not that complex the right people skills might even end up more important.
Oh and definitely noticed the being sick less frequently thing during most of the year, my work has changed to working from home when it first started here. Even in normal times I don't really go to many places so I've missed out on many of those mild but inconvenient things last year. Periodically having dinner at my parents where either my brother and/or sister is present typically with 2 or more of the associated niece and nephews is a very reliable way to have an interesting time a few days later. As much as I enjoy not being sick I don't think we'll be avoiding those forever unless someone manages to come up with a practical vaccine for those, which seems unlikely given the variety of things out there and relatively low severity.
Plasma, not white blood cells. 🙂
Ah, that sounds right. I'm definitely not a biologist.
@@BigClive Neither am I. Like you I have a broad range of interests. :)
A very timely video for me, as I needed to take one of these recently and was wondering how it managed. Though luckily mine only required some shallow nasal swabs.
i'm not going to pretend i'm an expert, but i've heard from several sources that covid19 lives deeper back in the nose/throat and so it's way more concentrated there, so i'm wondering, are your "shallow swab" tests accurate enough?
@@ThorNado77 I’ve used 3 different brands of these lateral flow tests. The instructions with the 3 I’ve used all said to just put it 2.5cm up or until you feel resistance. Some of them also ask you to swab your tonsils before swabbing your nostrils.
How did you figure all this out?
I went on a Google hunt.
that cool. very interesting. I like excellent explanation for the masses! I think "C" = control and "T" = Test..
Thats the older revision test, in the new one the carrier solution is already in the bottle, with foil lid :)
It’s not based on age, just which producer they come from.
New version also is nose only, so no more gagging!
@@Pugjamin Nope, the nose ones only became available more recently. The old style ones are being phased out as supplies are used up, though you may still get them for a while.
I've been doing that type of test once or twice a week for a few months and it does get easier to accommodate the invasive nature of the probing. Now I don't notice any discomfort.
imagine a deadly virus so deadly you need to test to confirm you have it and not just a normal cold...
Yes. Because you might not have symptoms, but your nan will die if you go near her. The test is not for you, it's to protect others.
@@DaedalusYoung i have a chronic illness, cant have the jab for medical reasons, very low immune system. flu 5 years ago almost killed me again no jab, i caught covid this year and it was absolutely nothing to write home about, my nana is actually healthier than me . but again covid aint shit. loose weight eat healthy get sunshine and live your life,
@@DaedalusYoung The jab wont stop you killing your gran if she's going to die from it, it does'nt stop the spread of Covid - only reduces the symptoms and less likely to spread but does'nt stop it, you must lock yourself away and never come out !!
@@customcutters You were lucky then. There's still on average 120 people dying. Just because you had no ill effects, doesn't mean that everybody else has the same response.
@@custommadeknives We're not talking about the jab. We're talking about the test.
Used one yesterday just to check like you, I was also wondering how it was really working 😁
Were you feeling ill?
@@JamesSmith-vz8yr yes, looks like it's just a cold ¯\_(ツ)_/¯
@@cuteraptor42 It's always just a cold mate.... (they are lying to you 💉🐑)
@@JamesSmith-vz8yr Careful now. Waking them up too quickly can be harmful. Need to do it gently.
@@haywoodyoudome Some people are beyond help mate....
The interesting thing about the Urine Strips is they test for unusual things like Specific Gravity and the presence of Leukocytes from leaking Kidneys. Chemical tests are one thing but some of the tests are much more 'mechanical' in nature.
One of my friends worked in an old folks home and sent his mate a piss stick with the message “if it goes black you’ve got about three weeks”. He’s still alive so presumably it didn’t.
Those are colorimetric tests not LFAs
I have some of the dip-in test strips. They're quite impressive in the number of tests they perform simultaneously.
biomolecular TLC!!! this is so cool
Funny how you need to shove the sample wand up into your brain, but it's so contagious you need to stay 6 feet away and cover your face, unless you are a politician at cop26.
I hadn't thought about all the cop26 junket freeloaders being huddled together. One can only hope......
I am waiting for the scientific community to announce that this entire thing has just been a giant double-blind trial with a placebo 'cure', because it feels like none of the statistics actually support the theory that what we're doing has made any meaningful overall impact.
I should point out there is one which only requires both nostrils rather than choking yourself, which is vastly preferable (still sneeze a lot though). Forgot which brand that was, NHS do hand them out but I think only in schools, my daughter brought some home
I got some of those through the standard NHS online request. Think they’re more expensive so are only used when the other version is low/out of stock
Interesting. Here in Germany, nostril tests are standard while some tests, especially for young children, offer the alternative to sweep inside the mouth. Since literally all tests come from some Chinese factories and look more or less the same, I wonder if there is really any difference in the test material, or just some regulatory reasons, why we don't choke ourselves. 🤷
@@gisobo There are a couple of differences between that test and the one Clive looked at here, the liquid is already in the dropper and that's sealed with foil, says to use 4 drops not 2, and I think it says 15 minutes not half an hour. The one Clive has there does say you can use only a nasal swab but it'll probably be less accurate. Also that one tells you to blow your nose before administering the test, whereas the nostril only one I have doesn't.
Sophisticated and amazing science, yet there are twats that still think it is all fake. Great video @Clive, and stay safe mate!
In the version I’ve been supplied by work, the solution is already in the dropper tube, with a foil cap to peel off (with some difficulty) before use. Also, the instructions only ask you to swab both nostrils, not the throat. And the result only takes 15 minutes.