I need to make some kidney stones and not in  the traditional way, because I wanna try out   a potential home remedy for preventing them.

That's great, we got calcium oxalate crystals.

Kidney stones come in a couple of  different types.

You have calcium stones,   you have uric acid stones, you have cystine  stones, and you have struvite stones,   and all of those describe what it's made  out of.

And so yes, I also did wonder what   struvite was.

So let me lemme show you that.

Struvite is magnesium ammonium phosphate,   and it turns out you only get this kind of stone  if you've had a UTI with a type of bacteria   that turns urea into ammonia through an  enzyme called urease.

Biology is wild.

We're not talking about that.

What we care  about today are the most common type of kidney   stones called calcium stones.

These are typically  things like calcium phosphate or calcium oxalate,   or sometimes a little bit of both.

So what I'm  gonna be trying to make today are calcium oxalate   stones.

And I had a plan to do this.

So my plan  was to mix calcium chloride with sodium oxalate   and then get out calcium oxalate and salt.

This  is what I wanted, that's the calcium oxalate.

However, when I opened up my package from Amazon,  I did have calcium chloride, that's great.

But   then instead of the sodium oxalate, they sent  me sodium perborate tetrahydrate, what's that?

I noticed because it had a lot more  danger, danger warnings on it than   I anticipated.

So now we have is calcium  chloride plus sodium perborate.

and that,   do you know what that makes, 'cause I don't?

I don't know what that makes and I'm not gonna   find out.

You can figure that out if you  want to.

We're not experimenting with this.

And so we improvise because I don't throw  things out.

And so I have a leftover bag of   oxalic acid from the antifreeze video,  ethylene glycol, because I was showing   the terrible things that happen in your body if  you drink antifreeze, which is basically kidney   stones just everywhere.

Anyway.

So now what  we have is calcium chloride plus oxalic acid,   and those together will also make calcium  oxalate.

But instead the other product will   be hydrochloric acid instead of just sodium  chloride, which I'm a lot less excited about,   so thanks, Jeff Bezos, just making  me make hydrochloric acid over here.

Did I balance this right?

Calcium, calcium,  two chlorides, one chloride.

Oh, oh,   no.

Two HCL.

Now we're balanced.

So this  is called a precipitation reaction.

The   ions in the solution are so concentrated  that when they combine, they're no longer   soluble.

Oxalic acid is a pretty weak acid and  it won't totally dissociate in water right away,   but as the calcium starts precipitating out  with the oxalate that's available, more of   it will dissociate to replace it.

Yeah, oh yeah,  that's working.

I love it when chemistry works.

This is not in the script, but I'm adding  it in because I think it's kind of cool   to understand here.

So oxalic acid, you know,  when it's just sitting in that bag like that,   has this kind of structure.

However, when you put  it into water and we talk about that dissociation,   what happens is that you get oxalate.

And so we  lose these two hydrogens.

What a funky looking   molecule, right?

And the reason why this works is  because actually those negative charges are shared   between the two oxygens.

So sometimes you  can also write it like that, so that like   these two oxygens are sharing that negative  charge, and these two oxygens are sharing that   electron kind of thing.

And so this is the like 2  negatively charged oxalate that then our calcium   can just like hang out by.

So that's how this  oxalate is binding to this calcium, cool?

Cool.

About two years ago, I woke up in the middle of  the night and thought that my body was trying   to implode, and it turns out that I had a  kidney stone.

And if you've had one too,   you know that you wanna try to avoid  getting another one.

Now I heard that   one way to prevent them was to put lemon in  your water.

But like do you know how little   lemon juice there is in a slice of lemon?

It's  1.62 grams, but I also got two seeds in there.

Stomach acid is like 1.5 to 3.5 pH, lemon juice  is about two, so like could adding just a slight   amount of acid to your stomach actually have any  effect on your kidney stones?

That didn't seem   right.

And actually that is right, because it  has nothing to do with the acidity of the lemon,   mostly.

So typically when you have  too much calcium in your diet,   what happens is that your kidneys just  flush out all that extra calcium in your   urine because that is what your kidneys do.

They  take all the stuff that your body doesn't need,   stuff like urea and ammonia and extra minerals  and vitamins and toxins and electrolytes,   and all that kinda stuff that is too much in  excess in your blood, and it gets rid of it.

But the way that it works is super cool, and  I love the way that the nephron works, because   what it does is you have a bundle of capillaries  called the glomerulus, great name.

So your kidney   pushes all the blood into the glomerulus at high  pressure.

And what happens is that everything   other than like big proteins in your blood gets  pushed out into a space called the Bowman's space,   which I also think is a great name.

So you have  your blood, everything other than big chunky   proteins gets pushed out, and then your body  decides selectively what it wants to put back in.

So all these extra salts and ions and junk end up  in your urine, including things like calcium and   oxalate, which make our calcium oxalate stone.

At normal levels, both of these ions just get   diluted in your urine and excreted out.

However,  if the levels get too high, either because you're   dehydrated or maybe there's something funky  going on with your metabolism, they can come   together to create these crystals, basically  what's happening right here in this tube.

So what about the lemon?

The lemon juice could  stop it because of something called citrate.

You're probably familiar with citric acid,  which is what gives lemons their tang.

However,   when citric acid dissociates into its anionic  form in something like physiological blood levels,   you get citrate.

Citric acid, citrate.

Very  similar to the oxalic acid and oxalate we talked   about before.

So we have citric acid which  dissociates into the anionic citrate.

Now,   once again, we've lost these hydrogens off of  these OH groups, and now they have a negative   charge.

And you might be wondering why an  OH group can just like lose a hydrogen,   that doesn't happen in something like an  alcohol, right?

And again it is because   there's actually resonance structures  happening here between this O and this O-.

So here, this double bond O, OH, this is a  carboxyl group, and this can donate those   Hs because of the way that that electron can be  shared between the double bond and O and the O-.

So again, you could also draw this carboxyl  group that's lost a hydrogen here with this   resonance structure.

So actually these two would  be sharing this negative charge, and same thing   with this carboxyl group here and that one there.

So they're sharing that electron.

I feel like if   you're actually a chemistry professor, you must  have to spend so much time like perfecting your   handwriting.

And again, citrate is how citric acid  exists at normal physiological pH.

So if you're   drinking lemon juice, your body is dealing  in citrate.

And so doctors will sometimes   actually prescribe citrate drugs to patients  who have recurrent kidney stones because this   negatively charged citrate can actually go around  in your urine and bind to free-floating calcium,   preventing it from binding to the oxalate  and forming calcium oxalate kidney stones.

Citrate is a chelator, a name for an organic  molecule that binds to metal ions like calcium.

'Cause remember you could look at  this and it has a 3- charge on it,   so it combines to positively charge calcium  ions.

Okay, so at the top we have our kidney   stone equation where calcium and oxalate  come together to form calcium oxalate   kidney stones.

But if we add citrate into the  equation, now we can also get calcium citrate,   and that will push the equilibrium of this  top reaction to the left away from the kidney   stones.

So now we are getting fewer kidney  stones, which is a positive thing, we like   that.

So now let's try it in my little kidney  stone test tube.

All right, maybe we need more   than five mil.

I think that's not helping.

For  kicks and giggles.

Does not look very different.

So actually I think everybody just needed a  minute to work.

So I think there's actually   a pretty clear difference between citrate, no  citrate, and also all the precipitate in here was   starting to fall out of solution, so you couldn't  see the difference.

But like citrate, no citrate,   crystals, no crystals, kidney stones, no kidney  stones.

Okay, now that these have been sitting for   a bit, I think there is a clear difference between  the sort of straight kidney stone reaction and the   one with citrate.

I think you can tell like a  big difference.

The citrate really prevented   that precipitation.

But let's look for some  crystals.

And yeah we have... That's great,   we got calcium oxalate crystals.

But what I'm  gonna put next to this is the one with citrate.

Without citrate, with citrate, there's  just like dust that was on the slide.

So drinking lemon juice, lemonade, and even some  store-bought mixes can increase the amount of   citrate in your urine, decreasing your chance of  getting kidney stones.

Now drinking lots of those   fluids also means that you can be extra hydrated.

And did you know that you were supposed to be   producing like between 2 and 2 1/2 liters of urine  per day?

That's a lot of urine, that's a lot of   pee.

I mean, I've never measured, I'm not going  to measure.

I don't like where this is going.

Okay, so being properly hydrated means that the  concentration of all the things we're worried   about is lower, so lower chance of making  stone.

But not every citrate containing   juice seems to work the same way.

For example,  in some studies, orange juice seems to have the   most protective effect against kidney stones,  but grapefruit juice could actually increase   your risk of getting kidney stones, weird.

We're gonna try all three anyways.

Also,   remember how I said it was mostly not about the  acidity?

Ironically, some of these acidic juices   can actually make your urine more alkaline.

When that same citrate hits your liver,   it can be metabolized into bicarbonate, which  is alkaline.

That bicarbonate could make your   urine less acidic and prevent a different  type of stone, uric acid stones.

Less acid,   less acid stones, makes sense.

So it's not all  about the acidity, but it does play some role.

So obviously I ran this experiment three more  times.

I have equal parts calcium chloride and   oxalic acid in these tubes and then I added lemon  juice, grapefruit juice, and orange juice.

And   to prove that it is not just acid that makes the  difference, I also made one with vinegar.

Oh yeah.

We do have crystals.

Here's the thing that I think  is interesting though with the lemon one, is that,   do you see these like sort of diamond-shaped  crystals?

I don't think we saw many of these   sort of diamond shapes before, which reminds  me of more of like a tetrahedral crystal,   something like salt.

Okay, and now we go to  orange.

There's so much other junk in orange   juice.

It said no pulp, but there's for sure a  pulp in here.

These crystals are so much bigger.

Look at these like diamond tetrahedral crystals.

There are different shapes in here, so I do wonder   if it's forming other stuff, kind of cool.

Next up, we got grapefruit juice and vinegar,   not together.

It's hard, right, 'cause there's  definitely pulp in here too.

It's funny, I don't   see any of those like tetra... Oh, there is one.

All right, there's some tetrahedral crystals in   here too.

It's really hard to do a one-to-one  comparison of like more or less crystals with   this.

Yes or no is pretty easy, but like I don't  have the precision here to really say if one has   more or less.

Let's grab vinegar, we got those  calcium oxalate crystals.

Vinegar didn't solve it.

Now obviously I am not that kind of doctor and  you should not take medical advice from a random   YouTube video.

But if you happen to be a Falcon  tube with a recurrent problem of kidney stones,   I would recommend citrate and orange  juice.

When I wrote this, I actually wrote,   "I'm not a doctor," and then I was like,  "No, I am.

I'm just not that kind of doctor."

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