I don't know what PA is??
The Nicotiana rustica Absolute is thick, very sticky, the consistency of pine tar, and if gets on your fingers you can smell it for days! For optimum suspension it must be "cut"(thinned) with grain alcohol, I use 190 Proof 95% EverClear (white lightening). It's the only thing that works effectively, as a solvent.
The way I measure it is to let the vial sit in some hot water for a few minutes so it flows easier, and then use a little 10ml beaker with 1ml markings, and pour it from it's vial into the beaker, and then add my †Ethyl Malto/Grain alcohol solution to mix in the beaker. No muss, no fuss. Very accurate. I got my beaker on eBay for about $10, they're kind of expensive, but they stand up by themselves and are really handy. It's a little bigger around than a pencil, and 8" tall.
I use 2ml of of concentrated rustica to 5ml of EM solution, this is my "tobacco mix". I then add just a tiny "pinch" of pure Menthol (crystal form), not enough to taste it but enough to "cool" the flavor.
I usually make a double or triple batch, that way I don't have to mix a new batch everytime I need juice, I put it in a bottle of it's own, ready to use. By with my recipe, that bottle will make Twenty-one 10ml batches of juice. This flavoring is then subjective, some people like stronger, so you can increase or decrease the ratio of AB:EM to personal taste/aroma, but the ratio of ingredients I used stays fairly true to JCO™.
When I make a 10ml batch of juice (that lasts me about 5-7 days), I use only 1ml of this "mix" to my ECOpure Krystal(36mg/ml nic) +ECOpure Mixer (no nic) to give me 12mg/ml nicotine content, then add ½ml each of Caramel and Hazelnut extract full strength.
ECOpure is VG, by the way, MHO the BEST! Absolute is extremely potent, as you can see from the ratio, and as I said one 15ml bottle of Rustica lasts me a long, long time, more than a year. I'm now working on my second bottle!
I like a nice mild balance of flavor between Rustica/caramel/hazelnut. The hazelnut flavoring is one of the basic flavors in JCO and in Tenn Cured. The "Old" formula, that is. I have no idea what they use now. When it's mixed right, you should be able to just "pick out" each of the three flavors, but one is not more prevalent that the other two. That's "balance"! And Yummy!
†The Ethyl Maltol in grain alcohol is a 12½% solution, that's the strongest you can make it. If you dissolve it in any other liquid the percentage goes down. I use EM to "meld" the tobacco flavor, it soothes the high bitters and enhances the low "grassy" flavor of the absolute. More palatable to me, you really can tell the difference without it. Tobacco without EM is very harsh, and with other varieties of tobacco Absolutes can be severely "ash tray"!