What are Nicotine Salts
Nicotine salts are a type of nicotine that mimics natural nicotine as it is present in a tobacco leaf. A salt is made when acid reacts with a base (alkali). This is in contrast to free base nicotine that has been chemically modified for quick and efficient delivery into the body and brain for a more powerful nicotine effect. Most people have heard of freebasing of cocaine. Well, the chemical process is similar with nicotine in which it is turned into a more pure form for better absorbability by the body.Since the 60s, large tobacco companies, like Phillip Morris, have been conducting research for ways to increase the delivery of nicotine to the body for a stronger, faster effect in order to make cigarettes more powerful and addictive. They discovered that by freeing the nicotine from the acids naturally present in the tobacco leaf, they could achieve this. So why does it appear that some e-liquid manufacturers are moving backwards by turning free base nicotine into nicotine salts?
Note: This article will not delve deeply into the chemistry of free base and protonated (the opposite of free base) nicotine but will try to give you information in broad terms.
Free Base Nicotine
With traditional cigarettes, Nicotine is present in both the particulate matter and the gas of the smoke. Within the particulate matter, there are three forms of the nicotine – diprotonated, monoprotonated, and unprotonated. The gas phase contains strictly the free base nicotine form. As you can make out, unprotonated means it does not have any protons, hence it is a free base. This form of nicotine is most easily absorbed into the body and brain and provides a quicker and stronger effect.
Free base nicotine is also more lipid soluble and crosses the blood-brain barrier more readily than other forms, leading to the release of dopamine. Scientists indicate that higher levels of free base nicotine entering the lungs correlates with a higher initial strength or kick and addictive potential of the nicotine. (National Institutes of Health 2005).
In its natural form, nicotine, as it is contained within the leaves of the tobacco plant, is not a free base but exists with acid in the form of a salt. This type of nicotine is less absorbable by the body. When certain types of acids are added to free base nicotine, those acids not only turn the nicotine into a salt, but may also help to free the nicotine (into a free base) when heated to a certain temperature – as during vaporization. At least this is the claim of Pax Labs, Inc., which obtained a patent for a nicotine salt in 2015.
Additionally, when nicotine salt, also known as nic salt, is used to make e-liquid instead of the pure free base form, the quality of vaporization supposedly changes; the hit is smoother, making inhalation easier. In the free-base form, nicotine “bites” the throat, as it is very alkaline. But in the initial salt form, a higher concentration of nicotine may be more tolerable for inhalation, allowing the user to experience a stronger nicotine effect without the harshness.
Pax Labs, Inc.
As noted, in 2015 PAX Labs patented their JUULsalts formulation of nicotine salt for use in its e-cigarette device, the JUUL. The compact low temperature device utilizes e-liquid pods that contain high levels of nicotine (in the form of nicotine salts) – 59 mg/ml per pod – intended to match the strength of a traditional cigarette. In general, the e-liquid industry standard for nicotine content ranges from 0-24 mg/ml. Most high wattage vapers use lower nicotine levels because with the powerful sub-ohm devices, they are able to now match the nicotine blood absorption rate of a traditional cigarette (PubMed 2016). “Consumption is different from absorption; the main factors associated with the effects of nicotine are the levels in the bloodstream and the speed of absorption” (National Institutes of Health).
The company claims that they use an outside organization to research their e-liquids. In the patent description, reference was made to the prevailing conclusion that free base nicotine compositions generated greater satisfaction over nicotine salts in a combustion process that involves high temperature. Their patent states that there are conflicting results.
The patent goes on to describe an “unexpected” discovery that certain formulas of nic salts delivered greater satisfaction than free base nicotine with low-temperature vaporization and matched the satisfaction of a traditional cigarette. The Pax website indicates that they add benzoic acid to the JUUL salt e-liquid formula, and their 2015 patent indeed states that “the nicotine salt formulations are formed from an acid with a vapor pressure that is similar to the vapor pressure of free base nicotine at the heating temperature of the device.” In other words, they’ve made it as volatile as possible to be effective in low temperature devices. Furthermore, they discovered that certain nicotine salts (using different acids) yielded better performance than others.
The natural form of nicotine as it exists in the tobacco leaf is by nature more stable and less bio-available to humans.
It’s All in the Type of Acid
According to the patent, the maximum concentration of nicotine in blood plasma and the time taken to achieve the maximum concentration were both achieved by certain nicotine salts ahead of other nicotine salts and free base nicotine, all when delivered through a low-temperature vaporization pathway. In other words, some types of acids worked better than others in terms of creating a nicotine salt with efficient delivery into the body when vaped with a low temperature device.
They found that using acids with particular vapor pressures achieved the highest concentration of nicotine in blood plasma as well as the fastest uptake time. A higher vapor pressure corresponds to a lower boiling or vaporization temperature. The level of nicotine that was achieved by the patented commercial nicotine salt was 5 ng per ml at 1.5 minutes. One and a half minutes was the time measured after the first puff in a series of 10 thirty-second spaced puffs. Among a test of various nic salts as well as free base, the least satisfying was free base.
A heart rate of 1.2 times the norm was achieved 40 seconds after the first puff by the patented nicotine salts composition, while that of the free base composition did so in 110 seconds. In two minutes, a heart rate of 105 to 110 beats per minute was achieved by the patented nicotine salts formulation (also matched by a traditional cigarette), while a nicotine free base formulation only achieved 86 bpm at 7 minutes.
Pros and Cons of Nicotine Salts
- Longer shelf life and less oxidation. Nicotine in its natural state is more stable and less likely to oxidize. Oxidation of nicotine in e-liquids causes an off-flavor and discoloration.
- Possible smoother hit. This is due to the lower alkalinity of the nicotine salts. Alkalinity, e.g., free base, is commonly associated with the “bite.”
- High levels of nicotine. The trend is to offer very high levels of nicotine in these types of salt e-liquids. This may be very helpful for people who are trying to quit smoking. Although it is now possible to match the nicotine uptake of a cigarette by vaping high wattage devices, nicotine salts may provide a way for low wattage devices to match, or surpass the amount of nicotine absorption as smoking a traditional cigarette.
- Less vaping required to achieve nicotine satisfaction. With higher levels of nicotine, less vaping is necessary and the Vaper may put down the device more often resulting in less usage of battery and e-juice. This could provide a noticeable cost savings.
- The high levels of nicotine commonly offered with “nic salts” may also be a disadvantage for some people who do not desire high levels of nicotine. The Pax JUUL, for example, does not offer zero or lower levels of nicotine.
- It is not recommended for high wattage or sub ohm devices.
- At Nude Nicotine, nicotine salts appear to be more expensive than regular nicotine. Whether or not this translates into higher prices elsewhere has not been evaluated by us.
- Uncertain effects of benzoic acid. This is the ingredient that supposedly gives the JUULsalts its desirable qualities. Although benzoic acid is considered to be relatively non-toxic, the following excerpts are for your information.
In conclusion, nic salts may help to fill a market void. Before nicotine salts came around some people may have wondered, “How can we get higher levels of nicotine and absorption (and satisfaction) from a small, discreet, low temperature device?” Perhaps we now have an answer.