I was feeling a bit under the weather, and i thought, let's give myself one of these lateral flow covered tests, just to confirm that i've not somehow picked up covert, even though i am vaccinated, it came back negative such to come regarding cold. However, i thought that these were quite interesting, so i've found out how they work and i'm going to explain how they work. Now, i'm also going to explain how the test is done so to do the test. You get these little dropper bottles and you get a carrier solution here.

You snap this off and you pour the small quantity of carrier solution into this bottle. You then - and this is absolutely the worst bit you get this little cotton tipped swab and you have to stick it into the back of your throat sad throat, that's a tonsil area, i i don't have tonsils, don't know or or that area, and then you rub It around neither side, that's when you gag it just about made me throw up. Then you stick this up your nose and you twirl it round and run the nostrils, but you have to push it right far to the back and you'll, probably sneeze as well. It's very intrusive once you've got your sample of stuff, you place it into that liquid and you press it around to really mix in with that liquid and then once you've done that for about 15 seconds, you squeeze this little plastic tube, and then you drag it Out so it squeezes it off the pad, and you end up with as much of a concentrated dose in there as possible.

I'm keeping this plan, i'm not going to contaminate it, because i i want to keep that test. Then you pop this lid in and you have a little squeezy dropper bottle. Quite clever. You put a couple of drops into this reservoir here and it starts the process of wicking along inside and after about 30 minutes uh, you will have a indication either.

Just the c, a line will appear or t for a positive conformation and the c, which is the confirmation line. But let's take a look inside this bit and see how it does that clue. It's incredibly clever, but strangely simple as well and there's a lot of connections with pregnancy tests are doing the same for a hormone. She popped the lid off.

Let me zoom down in this and just show you actually you know i've taken a picture. I could show you, but i shall zoom down. I shall zoom down and show you what's in here in fact i'll just zoom right up to here, so you can actually see the real thing in a closer vicinity. So here's a pad that takes the liquid.

It soaks along and then it goes to this waste pad here right. Tell you what let's uh, bring a picture and i'll show you the whole process here so inside is this wicking pad and it's formed of multiple materials, multiple layers with chemical, impregnations and parts of it. When you put the carrier liquid in with the potential virus, it lands in this area and absorbs into this large area wicking pad, which is quite thick, and then it starts wicking along this, a blotting paper up to the other end as it does so, it passes Through this zone, when it passes through this zone, it has sort of molecular keys with dye on them and by dye, i'm i'm actually talking like gold molecules. It's a tiny, tiny, infinitively small amount gold, but enough to create this of the red lines that are seen so as it passes through.

If there are the virus particles it latches onto them, with that marker dye, it then continues up through two areas which has mil which have molecular keys. The first area is the test area, and if the molecules do have the virus, then the virus is trapped onto these little test keys and it makes the die visible. At that point, it causes a concentration of the die. It then continues up and there's another set of keys that will just generically latch onto everything and else as it passes, and the whole point of that is to show that the whole process has happened properly, that the chemicals were right and that the whole process did Go through this zone to actually display the test.

The liquid then continues into this pad, and that is just basically the waste pad where it just collects all the residue, and that's fundamentally it just for the fact that these antibodies this these little keys that latch onto that signature will make the line visible. That is fundamentally how the test works. It's very clever, very strong hints of the blotting paper, the sort of the filter paper chromatography. If you remember getting that at school, i don't know if they still even do that anymore, but they've got other versions of these.

That can do multiple tests at once, so you can actually have a whole load of lines that has a liquid pass. That will run a whole load of tests and it's not just things like it's, not just that sort of mucol stuff in the carrier liquid. You can use urine in them. You can also uh extract the when they put blood through it.

They separate the red cells from the white cells, so the actual just the white cells, the color, doesn't interfere with it and that can also be used in similar stuff. Like this, it's very clever, very neat, and you think you know it's so simple, but in reality that simplicity underlies the fact that the scientists have engineered these molecules to lock on to a particular keyed signature of the virus. It makes it very clever. So if you're wondering how these little tests work, that is how they work.

It just seems so simple just that liquid flowing along blotting paper, but the science behind it is incredibly sophisticated and very impressive.