Houston, we have a problem...BE nic titration results

[ambientech]

Vermont Vapor adds citric acid to lower the pH of the base nic they use to make their 35 mg, in order to reduce the smell. I know this for a fact. Some flavors have acids in them and might cause a false reading.

Kinda leaning towards the no nic thing though...nic juice WAS included in the titration, right? Sorry, had to ask.

The more I think about it I vaped 3 times as much of her juice than I do AVE

I feel duped and not too happy about it right now. I wonder how many vendors out there that are doing this ? I am new to vaping and I thought that different flavors was the reason for less throat hit but I am now finding out that it was me being ripped off for less nic and having to buy 3x as much juice. I guess if the vendor doesn't get caught it is a pretty good way to make more money.

 

[Kurt]

Kurt, I went ahead and gave this a try. I added 1ml of 36mg labeled 25%VG/75%VG. 4 drops blue, and roughly 40ml dis water. I'm using a 3ml syringe. I did the test, but found it EXTREAMLY difficult to see the color change because the 'yellow' is basically clear. It goes blue to green to greenish-clear to clear (it you look VERY hard you can see yellow) So I did it again, but only used 10ml water, and 8 drops blue. The yellow was bright as day now. It tested to 35.046mg. I did not read the final volume in the glass. I started off with 2ml of acid in my syringe, and when the solution turned yellow, I stopped, and there was 0.2 ml acid left in the syringe so I used 1.8ml acid. (1.8x19.47=35.046). I did the same test with grad cylinder and result was exact the same (using 2 drops blue). Of course I’m very used to the kit, and I know how to read the markings. So it seems the amount of blue does not effect the amount to much.

I think 10ml water should be enough for 100%VG, (which I don’t have) but if not, could prolly use 20ml water and 12 drops blue maybe? I might try it again with about 20 drops of blue see if the results are off.

One thing noted in the test instructions is the margin of error of reading the cylinder. And the cylinder does come with 0.1 graduations. If someone reads off by .1ml the test will be off 2mg, regardless of the strength of nicotine. So 100 could test at 98, and 10 could test at 8. (Where one is 2% and the other is 20%) That’s why its states margin error +/- 2mg, not +/- 10%.

I can see how a newbie to this could mess up the readings, and they why you want to eliminate the cylinder, and go with the syringe. I kind of agree. There is one draw back to the syringe. It needs to be new and fresh. As a DIY’er after a syringe gets used a while, it starts to get ‘sticky’ and adding drops of .05ml at a time becomes very tough. (plus you have to have a steady hand)

Excellent work! I would not use 12 drops of indicator, however. It is in of itself an acid. too much and the results will be shifted. I have to apologize: I should have done all this in the lab before giving detailed advice. I am giving general titration advice, independent of BB details. As I said, its not an easy one to use, and all indicators have their own optimal ways to use them.

One thing, however, and forgive me if I sound like a jerk, but you got 35 mg, not 35.046 mg. The acid is only 2 significant figures (0.17N, 0.170N would be 3 sig figs). I explain this to my students all the time: just because your calculator tells you many places past the decimal, it doesn't mean you payed for those places, so don't claim them as a measured known. I intend to get to 4 sig figs precision with curves, but this will take some doing, as I have to standardize my acid to 4 sig figs from NaOH standardized to 4 sig figs. Bottom line is you got the labeled nic. Not sure about the 2 mg thing you mentioned, but I will think about it when I am fresher.

I am genuinely impressed with your efforts, however! Nice work!

 

[mjradik]

I think Kurt's getting some sleep, but this is great feedback! That the amount of blue does not affect the result significantly is really useful to know - and other tips.

Key point : feel free to use more drops of blue to see the color better.

It's really encouraging that this test kit works well (for unflavored liquids at least; and some flavoreds)

ps: did you see the posts about using digital weighing scales? A bit more maths, but if you want to be really really accurate ...

Yes, I did see the stuff about the scale. One issue with that is 25/75 pg/vg will weight different from 50/50, 75/25 and so on. So the person has to weight EXACTLY 1 ml of the test liquid first, and can’t go by a ‘standard weight’ of nic juice. Also, which I’ll touch base on in the 4th paragraph, when weighing the 1ml nic, it needs to be EXACTLY 1ml. When measuring weight to 3 decimals, 1ml will weigh differently from 1.05 or 1.1. The only standard will be the weight of the .12N acid. So I would say throw a glass on the scale with 1ml juice, and 10-20ml distilled water, and 8-12 drops blue. Zero out the scale now. Then do the test, and when the solution turns yellow, read the new reading and do the math using the standard .12 acid weight, and get the resulting mg.

Update on the blue factor. I did the test 3 more times using 20ml water (what would be needed for 100% VG I think BUT if 100%VG works with 10ml water I think that would be better, depending on the size of the glass). 8 drops blue was kind of tough to see yellow, but still possible. 12 drops blue, made seeing yellow good. 24 drops of blue made it VERY easy.. looked like dark/dehydrated piss.. lol. The results were 36.993/35.046/36.993. So 1.8ml/1.9ml/1.8ml acid.

So to me, it seems the blue does not have an effect on the outcome at this level. My results varied the way they did I think because I might have added 0.1ml extra NIC in my second test AND/OR accidently added 1-2 extra .05ml drops of acid at the end. Also due to reading the lines on the syringe. (Its late lol)

So, regardless of how the test it done, there still is that +/- .05-.1ml fudge factor. And going back to the weight. Since different PG/VG combinations will weigh differently, the user still has to weigh exactly 1ml, and if he doesn’t measure the 1ml exactly, it still brings in the +/- .05ml fudge factor.

I think the only way to reduce the fudge factor is to increase the amount of nic. I just did the test with 3ml nic juice, and used the multiply factor by 6.49 (19.47/3=6.49 because I tripled the amount of nic.) So I added 3ml nic, 20ml water, 12 drops blue. I ended up adding 5.6ml of acid. 5.6x6.49=36.344. So the result here is the nic strength is 36.344. Looks better. And if my measuring is off a bit, misreading 0.1ml either on the nic or acid, it will only throw off the result by +/- 0.649mg, not about 2mg as in the original method. But now were getting into DVAP’s original method where he used 10ml of juice. Using 10ml juice, and a multiple factor of 1.94712 is FAR more accurate than the scale is. But that wastes a lot of elquid, taking us back to 1ml and a fudge factor of 2, is ‘good enough’ for the averge person.

 

[Kurt]

Intersting. Will look into it in the coming days. I don't think the acid addition is wise as they will not vaporise.

I thought initially that this will still be testable with curves, but the citrate will make the whole thing amphoeteric and buffered.

Yes, you are exactly right. The salts do not evaporate as easily. I think only GC-MS can be accurately used with pH-lowered liquids.

No haven't been drinking. I just get very precise and rather obnoxious when it comes to chemistry wording. I need to get over that a little. Maybe a glass of wine...salut!

 

[progg]

Okay...My take on this situation. SNIP

Okay...This has gotten way way too long.

Pete

With all due respect, on the contrary, what this whole episode proves to me : yes, further vigilance is necessary for this relatively new product(s).

Both the actions of the those involved in ferreting out the tainted product, and the pressure they applied via nongovernmental means, worked. Government oversight does not guarantee detection nor speedy resolutions. It does guarantee loss of freedom.

Well done, to all involved.

 

[mjradik]

One thing, however, and forgive me if I sound like a jerk, but you got 35 mg, not 35.046 mg. The acid is only 2 significant figures (0.17N, 0.170N would be 3 sig figs). I explain this to my students all the time: just because your calculator tells you many places past the decimal, it doesn't mean you payed for those places, so don't claim them as a measured known.

No you don't sound like a jerk. Thank you for that teaching leson I did not know that. Makes PERFECT sence. I'll remember that. So my test I just did with 3ml juice was EXACTLY 36.. right on! So if the result is 24.991 is that still 24? I mean now were picking hairs for what this pertains too, just curious. No average vaporer is going to care if its 24 or 25, or 99 or 100. 'Close enough'. But in the lab'legal world, it really matters I'm sure.

 

[Kurt]

No you don't sound like a jerk. Thank you for that teaching leson I did not know that. Makes PERFECT sence. I'll remember that. So my test I just did with 3ml juice was EXACTLY 36.. right on! So if the result is 24.991 is that still 24? I mean now were picking hairs for what this pertains too, just curious. No average vaporer is going to care if its 24 or 25, or 99 or 100. 'Close enough'. But in the lab'legal world, it really matters I'm sure.

It would be 25. You round up for this one. 24.499 would be 24. And you did not use 3 mL. You used probably 3.0 mL, since you had a line to set it to on the syringe.

If you notice, all my numbers I give are without places past the decimal. technically I got 120 mg for the one result, not 121 mg, but I just realized that. 120 is 2 sig figs, 121 is 3, 120. is 3. You can make a claim to digits only if you can actually measure them. Its not obvious as to why 0.17N would translate to 2 sig figs in the final mgs, but I will try to write something to post detailing these things.

I think if people want to use chemistry methods to test something, they should understand the limitations of the measurements, as well as the limitations of the method itself. But you definitely got good news on your nic tonight, eh? Knowing that, and that you yourself measured it, I bet feels pretty good.

 

[Kurt]

Holy cow, its 3 AM...again!! Time for sleep. Congrats to everyone. We did good this week, all of us.

Good night!

 

[mjradik]

Holy cow, its 3 AM...again!! Time for sleep. Congrats to everyone. We did good this week, all of us.

Good night!

Ditto..... Kurt did you see my post about the 8,12,24 drops of blue, and using 3.0 ml liquid? (with the exception of using decimal places on the result because I didn't see you .12N comment till after) Am I accurate on reducing the 'reading fudge factor' inherent to the test? I don't want to give misleading info?

is there a technical name to the 'multiply factor' I refer too?

I'll be sure to use proper sig fig's/non-decimal places from now on, and i'll go back and update all docs/pages/etc correcting all that... Just to be accurrate. Thanks for all your help.

 

[Circumspice]

It would be 25. You round up for this one. 24.499 would be 24. And you did not use 3 mL. You used probably 3.0 mL, since you had a line to set it to on the syringe.

If you notice, all my numbers I give are without places past the decimal. technically I got 120 mg for the one result, not 121 mg, but I just realized that. 120 is 2 sig figs, 121 is 3, 120. is 3. You can make a claim to digits only if you can actually measure them. Its not obvious as to why 0.17N would translate to 2 sig figs in the final mgs, but I will try to write something to post detailing these things.

I think if people want to use chemistry methods to test something, they should understand the limitations of the measurements, as well as the limitations of the method itself. But you definitely got good news on your nic tonight, eh? Knowing that, and that you yourself measured it, I bet feels pretty good.

OMG... After reading the above, then rereading it... (math is my Achilles Heel)

I am so glad all you chemist types are on our side!!!

THANK YOU!!!

 

[Spazmelda]

Would it be a good idea to start a new thread for people who are doing home testing? I thought about doing this, but my kit hasn't come in yet. It could be a place where we could compare results and techniques. And we could discuss what juices seem to have added acids, etc...

Or does everyone just want to keep all that going in this thread?

I had something else I wanted to say, but I forgot. Oh yes, it was with regards to one company saying that testing was going to at $10,000/month. That is way excessive. This doesn't have to be that rigorous. Like Kinaboo (or someone said) proper procedures with some SMART testing can go a long way towards fixing this problem. A company should not have to test at every single step, but they do need to have testing at the appropriate step(s) and proof of process (so maybe some additional, more rigorous testing while they are developing their methods of mixing, diluting, bottling, etc...) Once the processes are proven, more limited testing would suffice.

IOW- the procedures are as important as the testing. With smart protocols testing does not have to cost an arm and a leg.

 

[Switched]

OK after a few moments of thought, I wonder why the recall is limited to that time frame? If he has tracked down the problem to this time frame, why is he suspending sales now?

IMO so he can get the proper protocols in place to ensure it doesn't happen again and to ensure that he didn't and won't miss any in the future. In all honesty, at this point in time who would buy anything?

Folks need to remember that when the volcano blew, he was pretty much caught with his pants down, that much was obvious (to me anyway) during the interview. He might have sought counsel by then, but I believe he has counsel now and is probably acting on the sage advice of counsel, if not having a second look at himself and his operation. He did himself some serious damage, now it is merely trying to keep the ship afloat after initial damage control. He will need to gain consumer trust once again (bringing the ship in for repairs) before he can put out to sea for smooth sailing once again.

 

[Switched]

What I am thinking is this:

You need:

2 syringes
BB
nic liquid
H2SO4
Distilled water
A tall glass that you can swirl about 40 mL of liquid without splashing

Use syringe to deliver 1 mL on nic liquid to the glass. Add about 20 mL of water. Swirl until completely mixed. Add 2-4 drops of BB, swirl again.

Use other syringe to little by little add H2SO4 to the glass, all the while swirling with the other hand (ideally...certainly swirl until fully mixed after each addition).

When the color starts to JUST turn yellow, you are done. Volume in the formula should be 1 mL + volume of acid added from the syringe graduations.

Kurt's Kitchen Titration.

I have done tons of titrations in my life time on boiler water analysis and boiler feed water etc... and all were conducted in a small white ceramic bowl and never in the cylinder (greater surface area) a small dow corning bowl would be excellent for this. One will see the small change in colour happen instantaneously at the surface when the drop is added - very difficult to see in my opinion in a 10ml cyclinder.

After swirling with the glass stirring stick that one drop will in fact change to the "indicator" colour and maybe just require one more drop or two thereafter (in order to maintain the "indicator" colour) at the proper indication point. I have a test kit on order and will see how that works and will report my findings. IME the test sample should remain clear and if it has gone to a chaulky colour, you have gone too far.

@Kurt
The info above is not for nicotine perse but what I was taught. Am I in the ball park? As stated I will know more when I use my kit and post my findings.

PS: For folks that are colour blind, this kit is totally useless it goes without saying

 

[Sylann]

This is starting to make sense now. I picked up some nic juice from box elder that was lot 256(VG) and 257(PG).

Every time I mixed with the 257 the juice came out wierd and just wrong. Tasted horrible even though I used Kosher VG and PG and top quality flavorings. I just figured I sucked at DYI. Maybe this has something to do with it.....

I did receive the mass E-mail Brad sent out and I sent a response back.

This is pretty scary.

On the brighter side of things maybe there is hope for my DYI abilities after all.

Who is the best vender to go to for top quality nic juice and supplies?

 

[Switched]

Would it be a good idea to start a new thread for people who are doing home testing? I thought about doing this, but my kit hasn't come in yet. It could be a place where we could compare results and techniques. And we could discuss what juices seem to have added acids, etc...

Or does everyone just want to keep all that going in this thread?

I had something else I wanted to say, but I forgot. Oh yes, it was with regards to one company saying that testing was going to at $10,000/month. That is way excessive. This doesn't have to be that rigorous. Like Kinaboo (or someone said) proper procedures with some SMART testing can go a long way towards fixing this problem. A company should not have to test at every single step, but they do need to have testing at the appropriate step(s) and proof of process (so maybe some additional, more rigorous testing while they are developing their methods of mixing, diluting, bottling, etc...) Once the processes are proven, more limited testing would suffice.

IOW- the procedures are as important as the testing. With smart protocols testing does not have to cost an arm and a leg.

Absolutely!

However, if I am not mistaken depending on volume and documented accuracy, I believe there is a minimum of samples required to be tested, and if proper protocols are in place an inspection agency can randomly grad a bottle of liquid and test it - and come up with similar results. I am sure there is a bell curve out there for this. Folks in the know please chime in.

 

[DVap]

is there a technical name to the 'multiply factor' I refer too?

The multiplier to convert acid volume added to reach the titration endpoint to a nicotine concentration doesn't have a name that leaps to mind. It's just a roll-up of all the chemistry and math involved... maybe call it a magic number?

When I developed the methodology on which the test kit is based, I had to match up the pH at titration endpoint with an indicator that would give the required color change within a drop of acid of the point where no more non-protonated nicotine was present. According to the graph I use showing degree of protonation of nicotine -vs- pH, this happens around pH 5.6. BTB leapt to the front of the pack for multiple reasons. It is yellow below pH 6 and blue above pH 7.6, and also possesses the green "warning range". At the concentration used, the amount of excess acid to get from pH 6 to pH 5.6 is quite minimal. Titrating with a meter and plotting acid volume -vs- pH shows this quite dramatically.

The chemistry hiding behind the acid volume required for the color change to yellow is simply moles of hydrogen ion added to the solution to achieve the color change. The moles of H+ added will equal the moles of nicotine present.

The chemist will ask, "How much eliquid was used, how much acid was needed, what was the normality of the acid, and what is the molecular weight of nicotine?". If 5.0 mL of 0.12N (normality being moles H+ per liter) acid was needed to reach yellow for 1.0 mL of eliquid, we have:

(5.0 mL x 0.12 moles H+/L) / 1000 mL = 0.00060 moles H+ required to reach yellow.

This means that the 1.0 mL of eliquid contains 0.00060 moles of nicotine.

The molecular weight of nicotine is 162.26 grams/mole.

So the mass of nicotine represented by 0.00060 moles of nicotine is simply:

(0.00060 moles x 162.26 grams) / 1 mole = 0.097356 grams of nicotine

Then:

(0.097356g x 1000 mg) / 1 g = 97.356 mg

and with 1.0 mL of eliquid used:

97.356 mg/mL

Using 2 significant figures, this gives 97 mg/mL.

It just so happens that 97.356 / 5 = 19.47 (a number familiar to users of the test kit).

If 2 mL of eliquid was used to get the same result, the math would work out to:

97.356 mg / 2 mL = 48.678 mg/mL

So the 19.47 multiplier can be viewed as per mL of eliquid used. (Simply apply the 19.47 multiplier and divide by mL eliquid used).

 

[Spazmelda]

Here's a paper I found the other day about using spectrophotometric determination of nicotine. http://colleges.ksu.edu.sa/Arabic C...ctrophotometric determination of nicotine.pdf

I don't know. Might be another (cheaper) alternative to GC. A spec 20 instrument would be sufficient for this analysis, and they are not that expensive, fairly low tech even. You'd have to do a standard curve each time, but once you get a some nicotine quantitated by another method you'd have enough readily available standard for thousands of assays.

 

[mj64]

I haven't seen this question asked. I assume there are independent laboratories that can perform nicotine % tests as well as chemical analysis of the content of liquids. What is a good resource to find these labs, and what types of certifications should they hold? Google gives me a zillion labs that do blood testing, but I don't really think a medical lab is the right type of place.

 

[kinabaloo]

I think it might be no coincidence that the recall came just after people started to receive their test kits and report findings. Perhaps Brad also received a kit that day.

Certainly the test kit will really change things in vaping land.

There are now thousands of random testers out there - it's a different world now

 

[markfm]

Search on "gas chromatography services".

The perfumers apprentice, a popular flavor source for many, does gc/ms. BE used them in early Nov, at least, to do a test. A link to the results is back around pages 28 - 30 in this thread, one of the emails from Brad; it showed 12.8% nic, which is consistent with what the first pass dilution is supposed to be.