Ok, so I've started building up a stash of Nicotine when the EU decided to limit sales to 20mg/mL and 10mL bottles. That went into effect in 2017, so the stash of 48mg/mL I have is now about 4 years old.
It has discolored somewhat during that time (stored at room temperature but in a dark place in brown 100mL bottles). So I decided to test the nicotine content by doing a weak base / strong acid titration with 0.1M HCl (I'm a chemist by trade and degree, so I know what I'm doing). Triple samples and all, using Bromothymol Blue as the indicator.
Rather surprisingly, it had not lost much, coming in in a tight band at 47mg/mL. So even a somewhat brownish-dicolored juice is still good to use.
To have a comparison sample, I obtained a fresh liter of 100mg/mL from Nicotine Giant. Much to my surprise, it only contained 89mg/mL. I guess I'll write them an E-Mail asking what that's about.
my dumbass read this as snorting nicotine..
Just by mentioning it, you lit a fire under some legislators ass. Laws to follow.
It has always been my understanding that just because nic gets discolored and oxidized that it only effected the taste. I never heard anyone saying that it lost potency.
I've seen a lot of dumbasses, with no actual testing capabilities, assure me it needs to be frozen. I've had 1 liter of freebase and 2 liters of salts doing just fine in clear plastic jars, in Tupperware containers, at room temp, in VG base, for well over 2 years.
Around 2013 I bought bulk 1L of 18mg ejuice for $40.
It tasted like ass, but I kept it around. Fast forward to 2019, I found that juice and gave it a try. By then, I "learned" that storing at room temp for so long would mean very low potency...
Absolutely NOT. Biggest head rush in a very long time after 2 years of vaping at 6mg.
Whenever I'm bored out of my skull, I'll take 15mL and play with that juice by adding different flavors. Actually gotten a couple decent mixes, but it's mainly for fun and didn't record the recipes :(
Did you make your endpoint the green color or the yellow? If your endpoint was the yellow, then you could have also been measuring the neutralization of the oxidized products like cotinine which has a pKa around 4.8.
Green, which should be about neutral. As with good practice, I continued the titration until it turned yellow, but that came very quickly after a few drops.
But even if, that would have only given me a too high a value.
Admittedly, I don't have a calibrated burette at home, so I used my electronic mixing scales (Resolution 10mg). I checked the calibration for those with a small 100uL Eppendorf pipette, which I do have. As they were dead on, and with the density of 0.1M HCl not deviating much from 1, I don't think I have too much error in the titration. With the titrated volume in the 5-6mL region, certainly not 10%.
Yea. You’re doing more than what most people would be lol. I guess that my question in nicotine titration is how accurate it is in distinguishing between different nicotine-like oxidation products. Like, you could have a 48 mg/mL nicotine at the start, but let’s say 10% is oxidized over an amount of time. These oxidation products still have that basic amine and could still be neutralized in a titration. So, you might be still be measuring 48 mg/ml of nicotine, when in reality, some of what is being neutralized is not nicotine and just has a pKa that is similar enough to trip in the titration. But, cotinine pKa is pretty low compared to nicotine, so I would imagine that titration with bromothymol blue would be able to resolve these two compounds. I guess the other question is what are those oxidation products? Cotinine is the natural metabolite in the body, but I haven’t been able to find any resources on nicotine oxidation simply from oxygen in the air. It could be other oxidation products with more similar pKas to that of nicotine. I also ended up talking with the CEO of Nude Nicotine (I think he is pretty active on this sub) and he was telling me that a lot of the times that nicotine will go bad with time is actually due to sulfur containing compounds that could be co-distilled with the nicotine and react with them over time and how pH is a huge factor in these reaction rates. I ended up going down a rabbit hole abs getting lost in my quest to learn what causes nicotine oxidation and bad tasting nicotine.
You're entirely right here. This is just a basic weak base / strong acid titration. Which means that at equilibrium the solution will be slightly acidic, with the pKa of the protonated nicotine base. Which is the same as the pKb of nicotine, 6.
This is why I chose Bromothymol blue. I did have some Phenolphtaleine at home, but that changes color at a slightly basic pH, around 8, so with a weak base it's not really usable.
That being said, the titration reacts on anything in there that's either basic or acidic, it's not specific. But the best one can do at home. For the fresh nicotine solution, you'd at least expect no other by-products in there besides Nicotine itself.
With access to a good organic lab, I'd probably use a GC, with a MS coupled to it to reliably identify the species coming off the column. Nicotine should readily evaporate to allow that and not having to resort to HPLC.
Sadly, a bit expensive for home use.
Did you test the old nic back when it was fresh? The 47mg test means nothing without a baseline. I've tested several 100mg batches and none were 100mg.
It means plenty. Like that the 48mg batch was probably made properly by the mfg and is holding close to its advertised level after 4 years. I'd say thats some good data even if there wasnt a baseline. Sure it could have started at 58mg and lost 10mg over 4 years but at least its CLOSE to what he bought unlike the new batch of 100mg/ml that's testing out at 89mg/ml.
What if that 48 was actually 100 because someone screwed up? I'll give that "means nothing" was a little overboard, but all it tells us is that it is close to where it was supposed to start at. Without knowing what mg it started at, we can only hope it lost only 1mg.
True.
I've made most of my 6mg juice from the 48mg base, BUT I also bought ready-made juice with 6mg on one or two occasions. I think that I would have noticed if my own juice was twice the strength.
Also, I have several batches of 48mg I bought from several manufacturers over time. I didn't test every batch because I didn't want to break open several bottles, but one other I tested (similar age) also came out close to its nameplate concentration.
No, I did not, didn't think about it at the time.
However, if it has degraded over time, it would have been well above 48 when it was fresh, wouldn't it? Hard to believe they'd put too much in it.
That's why I hoped I'd get my baseline from the fresh 100mg stuff.
There's been at least a couple times of companies sending out double the claimed amount. People thought they were getting bad nic when they were actually just getting free nic. You would know if it was double nic if you used out of that bottle before.
I'm sure I would've noticed, yes.
But at the time, 48mg/mL was the maximum amount permitted in Germany (where I got it). 100mg/mL was only available from obscure Chinese vendors. So it's rather unlikely that those vendors also had 100mg/mL in their production line.
wow. I wonder if all the brands have skimped on the nicotine percentages... and THANK you! I have been looking up and down for information on nicotine stored in a drawer and how long it lasts. I do plan on getting a mini-freezer, but right now I just have nicotine in a drawer in amber bottles.
Good to know. I accidentally bought 15 years worth of nicotine (2 100mg 1,000ml bottles) and I’m getting ready to break it down into 100ml amber bottles. I’m going to put it in a locked fridge and remove the light. Hopefully it lasts.
>I’m going to put it in a locked fridge and remove the light.
I'll let you in on a little secret. The light turns off when you close the door.
Yeah, my dumb ass tends to over think things. Haha. Probably should just leave the bottles not in use in the freezer in a black bag as suggested.
I wouldn't. I'd just store the 1000mL bottles in the freezer. If you're paranoid, put them in a black plastic bag first. But there's usually not much light in a freezer when closed ;-)
Breaking it down into smaller bottles only introduces oxygen into the liquid and the bottle, unless you have a N2 tank handy to expel that oxygen from the liquid by bubbling it through the PG for a few minutes.
15 years? I go through 500ml of 100mg nic a year.
I’m at 1.5mg strength. I Vape around 9,000ml a year. I did a calculator and it said 7.5ml/500ml. Is my math way off?
Yearly I’ll need 18 batches of 500ml. 7.5ml x 18 = 135ml/year.
1,000/7.5 = 7.4 years.
I have two of those bottles so close to 15 years.
Everybody is different. I've gone through about 500mL of the 48mg stuff in the last 4 years and I still have 3.5L left. So those original 4L are going to last me a as long as 2L of 100mg/mL, or 28 more years (32 in total).
No idea if the stuff is going to degrade significantly by then or not.
Hi. Thank you for the science! I think the main issue worried about is taste. Will it be harsh and/or peppery after 5, 10, 15, etc. years. Stored properly, I‘ve heard it being fine after 7-8 years. I don’t really think it’s worth worrying about.
I've been mixing from the same plastic 500ml 100mg bottle of nic for a couple of years now, never cooled it and it has been fine. I'm a lazy bastard with no fridge/freezer space and the quality has stayed the same as far as I can tell ( I mean I'm sure it's degraded somewhat, but still) Wonder what I'm gonna do when it runs out...
Has it turned to amber color like mine has?
Yeah I'd say deep amber, quite dark. My juice comes out like the second/fourth pic if you google "bud light in a glass" when mixing 2mls of this in a 50 ml bottle.
No reaction on my ticket to Nicotine Giant yet. Quite disappointing.
Anything yet? I’m just getting into DIY and my first order included a liter of 100mg from Nicotine Giant that’s currently en route to me, so I’m definitely curious about this.
I made the huge mistake of freezing a gallon of 100mg VG based Nic Salts. After three months I shook it vigorously like my typical gallons of freebase stored the same for many years. I decanted 8ozs into a canning jar planning to use some and then seal it with argon. After about 3 Puffs of this juice I found it hard to breathe and my head was spinning. It was also a slightly amber color. I contacted LNW thinking I got bad product and was politely educated on the merits of VG based nicotine stored in freezers seperating and being near impossible to mix at that temp. I was also informed that the nic salts in VG get that color for some reason. To sum it up, it would seem my partial gallon is more an unknown dilution ratio of nicotine because I poured off some pure nicotine that I further screwed up by diluting it before calling LNW. I'LL BE UNFREEZING IT! He, Keith, assured me that the product is well preserved in smaller containers kept cool and dark and all the better with Argon in the headspace. So I won't be tossing the gallon, I'll figure out eventually what the strength is after i remix it with a gallon lab stirrer and then split it up into much smaller bottles for boxes in the basement at 54°F Lesson learned is that VG Nic salts are not Freebase PG! Lol 😂