You might have seen the popular TikTok trend of melting a pot of vaseline (petroleum jelly) and putting your fragrances in to make the perfume last longer. Is this a good idea?

What should you really use for this hack?

Personally, I would not use vaseline for this is if were to try this hack. The reason being that vaseline has a smell to it naturally which can affect the smell of the perfume. You never want to mix your fragrance with something with an odor, whether it be natural or added! You'll want to use something with a neutral scent like jojoba oil.

However, it's important to note that not all fragrances will like being mixed with oil. Additionally, this will further dilute the perfume, which can affect the smell more than just the strength. So don't dump your whole perfume in! Try a little bit before you go all in!

What determines the lasting power of a perfume?

The short answer is, application area and the formulation of the fragrance itself. In order to thoroughly explain this, I'll have to show you a little diagram that demonstrates the science behind perfume!

Molecular weight:

As you can see (or read if you're using alt text), the things which are commonly referred to as "top, middle, and base notes" do have a bit of a scientific basis. Although, the cut off for each is subjective. The lasting power of a note is largely determined by the molecular weight of the chemicals that make it up. 

Base notes are mostly made up of chemicals that are heavier. This means that they take a longer time to fly away from the skin. This also means that they take longer to travel to your nose. This is why you smell base notes last!

Likewise, middle and top notes are medium and light weight molecules. 

The amount of aroma chemicals evaporating off the skin at any given time is known as the perfume's "sillage" or its "projection". 

Application area

People are often encouraged to spray perfume on their "pulse points". The reason for this is often to increase projection of the scent since heat makes aroma chemicals more volatile. Therefore, this often decreases the lasting power of a perfume. Personally, I apply perfumes on the pulse points and on my clothes.  My clothes, being much colder than my body, will hold onto each note longer, while my pulse points will increase projection, win-win!

However, the best place to place a perfume that doesn't last is probably the ends of your hair. This is the coolest spot on your body! This is why the scent of your soap or shampoo often lasts much longer on your hair than on the rest of your body.

Does using a perfume primer or thick lotion increase the lasting power of your perfume?

The short answer is, a little bit, but not as much as influencers will have you think. Unfortunately, due to the reasons highlighted above, the only real way to make a perfume last longer is to formulate it to last longer. Getting a perfume to last is one of the most time-consuming parts of developing a perfume. It's pretty easy to make something that smells good, but it's hard to get those good smells to last.

Scientifically speaking, the chemicals will last how long they last. No amount of primers or lotions or "fixatives" will increase the lasting power of a perfume more than a slight amount.

How do primers, lotions, and fixatives work on a perfume?

Primers

Primers might have sticky ingredients, much like a makeup primer. This will make it harder for the chemicals to escape your skin. However, the heat from your body will eventually break this sticky bond and allow the chemicals to escape. How long it holds depends on a variety of factors, including how hot you are, literally. If your pulse points run hot, your perfume might not last as long on you as it does on others.

Primers might also contain mild musks or other base notes to create the illusion that your perfume is still there. However, in reality, these aroma chemicals won't hold down the others in your perfume, they'll just last longer on their own. So, you're actually no longer smelling your perfume, but your primer!

Lotions

You may hear that using a thick lotion or simply moisturizing well will help perfumes last longer. I believe part of the reason for this is because people think their skin absorbs the perfume chemicals because their skin is dry. However it could also be because of the physicality of lotion. Since some lotions are thick, and could help capture the lighter molecules for a short time.

However, this likely isn't as effective as a sticky primer. This part of the article is speculation on my part since there isn't much research that exists on these products. Especially not independent research. My speculation is based on the fact that lotions are designed to be absorbed into your skin and perfumes are not, so they will part ways quickly, depending on how absorbable the lotion is and, of course, how hot your skin is.

Fixatives

Fixatives are marketed towards perfumers, but I have seen a few outsiders asking about them to help their favorite perfume last longer. Unfortunately, fixatives are just marketing! They work much like how scented primers work. The scent in the fixative is what lasts long, not the perfume itself! If you like the idea of using a more base-heavy perfume to layer with your favorite perfume, you might consider just getting 2 perfumes! This isn't always expensive, plenty of perfumers sell layering notes for cheaper than their full bodied perfumes. This will allow you to have control over how your perfume ages, rather than just using a fixative that has generic sheer musks.

If these hacks don't really work, what does?

Here are the things that have worked for me, as a perfumer, backed by science!

• Wear perfume on the ends of your hair or on an accessory that isn't close to the skin.
• They make little perfume necklaces that will have a far slower evaporation rate than your skin.
• Use a sticky primer.
• Use a layering base note that you enjoy!
• Popular layering base notes will be vanilla, cedarwood, sandalwood, sheer musk, and cotton candy.