The nicotine in most vapes comes from tobacco leaves, extracted using industrial solvents and purified into a concentrated liquid. A smaller but growing share comes from laboratories, where nicotine is built from scratch using chemicals derived from petrochemical sources, with no tobacco plant involved at all. Both types end up as the same molecule, but they differ in purity, composition, and how they got to your vape.
Nicotine Extracted From Tobacco
The traditional route starts with dried leaves of the tobacco plant, which naturally produces nicotine as a defense chemical against insects. To pull nicotine out of those leaves, manufacturers soak or boil them in a solvent. Water, ethanol, and chloroform all dissolve nicotine effectively. In a common industrial method called acid-base extraction, dried leaves are boiled in water, treated with sodium carbonate to release the nicotine from plant material, then the liquid is made highly alkaline (around pH 12) and mixed with chloroform, which pulls the nicotine into a separate layer that can be collected and concentrated.
This extracted nicotine is over 99% a single molecular form called S-nicotine, the same form your brain’s receptors respond to most strongly. But the extraction process doesn’t produce a perfectly clean product. Other plant alkaloids, phenolic compounds, and even trace heavy metals can carry over. Extracted nicotine also tends to have a hay-like odor and bitter taste, which is why many e-liquid manufacturers add heavy flavoring to mask it.
Nicotine Made in a Lab
Synthetic nicotine, sometimes marketed as “tobacco-free nicotine” or TFN, was first created by chemists in 1904. The process starts with a chemical called ethyl nicotinate, which is derived from niacin (vitamin B3), itself manufactured from petrochemical feedstocks. That starting material goes through a series of chemical reactions: it’s combined with another industrial chemical to form an intermediate compound, which is then converted step by step into nicotine through additional reactions including a final step that adds a small carbon group to complete the molecule.
The catch is that basic chemical synthesis produces a 50/50 mix of two mirror-image versions of nicotine: S-nicotine (the form found in tobacco) and R-nicotine (its mirror image). Tobacco leaves contain over 99% S-nicotine, so this matters. R-nicotine is less well studied, and its health effects aren’t fully understood. Next Generation Labs, a major synthetic nicotine supplier, sells this 50/50 racemic mixture. Other manufacturers, like the German company Contraf-Nicotex-Tobacco, add a purification step that filters out the R-nicotine to produce pure S-nicotine. A newer approach uses engineered enzymes to selectively produce only S-nicotine from the start, avoiding the need for that extra purification.
Why Some Brands Switched to Synthetic
Before 2022, the FDA’s authority over tobacco products was tied to the definition of tobacco itself. If a vape contained nicotine that never touched a tobacco plant, some manufacturers argued it wasn’t a tobacco product and didn’t need FDA authorization. This created a loophole that a number of e-cigarette brands exploited by switching to synthetic nicotine.
That loophole closed on March 15, 2022, when President Biden signed a law amending the Federal Food, Drug, and Cosmetic Act. The updated language gives the FDA clear authority to regulate tobacco products containing nicotine from any source, including synthetic. Products that are identical except for the origin of their nicotine are now treated the same way under federal law.
How Nicotine Becomes Vape Juice
Whether extracted or synthesized, raw nicotine isn’t ready for a vape. It first needs to be processed into one of two forms: freebase nicotine or nicotine salt. This choice shapes how the vape feels in your throat and how quickly nicotine reaches your bloodstream.
Freebase nicotine is the pure, uncharged form of the molecule. It’s created by raising the pH with a base (historically ammonia in cigarettes), which strips a hydrogen ion from nicotine salt and leaves the nicotine molecule “free.” This form is more volatile, meaning it vaporizes easily, but it also produces a harsh throat hit at higher concentrations. That’s why freebase e-liquids typically max out around lower nicotine strengths.
Nicotine salts work in the opposite direction. An organic acid is mixed with freebase nicotine to protonate it, creating a stable salt. Benzoic acid and lactic acid are the most popular choices in commercial e-liquids, though manufacturers also use citric acid, malic acid, and oxalic acid. The result is a smoother inhale even at high nicotine concentrations, which is why pod-style devices like JUUL use nicotine salts. These salts allow concentrations of 5% (50 mg/mL) without the burning sensation that freebase nicotine would produce at the same level.
Synthetic vs. Extracted: What’s Different
At the molecular level, S-nicotine is S-nicotine regardless of where it came from. Your body can’t tell the difference between a molecule extracted from a tobacco leaf and one assembled in a reactor. The practical differences lie in what else comes along for the ride.
Tobacco-derived nicotine can contain trace impurities from the plant, including other alkaloids and heavy metals. Synthetic nicotine avoids those contaminants but introduces a different concern: unless the manufacturer adds a purification step, the product contains 50% R-nicotine, a mirror-image molecule that doesn’t occur in significant amounts in nature and whose long-term effects in humans remain poorly characterized.
There’s also an environmental dimension. Tobacco cultivation accounts for roughly 0.2% of global CO2 emissions, and the crop depletes soil in ways that harm beneficial bacteria and fungi, reducing the productivity of land for future farming. Synthetic production sidesteps agricultural land use entirely and doesn’t depend on weather or growing seasons. For the individual vaper, though, these differences don’t change the experience. The nicotine molecule does the same thing to your brain either way.