They create a temporary tattoo that detects psychoactive substances in drinks.

A team of Korean researchers has developed a temporary tattoo that changes color when it comes into contact with the colorless, odorless drug used, usually dissolved in drinks, to facilitate sexual assaults or robberies.

The adhesive responds within a second to low concentrations of gamma hydroxybutyrate (GHB), a drug known as liquid ecstasy, which is used in cases of chemical submission (for example, to facilitate sexual assault or robbery) and can even cause death.

This new drug (GHB) is almost imperceptible to the taste and leaves no trace of color . Its effect is to induce a state similar to severe alcohol intoxication in the victim, making them extremely vulnerable to non-consensual sex or other crimes.

In recent years , cases have also been reported in large cities where criminals have used this drug to access victims' cell phones, using facial recognition, and steal money from their checking accounts.

Given the rise in these crimes , especially rape, preventive methods have begun to be developed, such as strips that can be placed in drinks and change color when liquid ecstasy is present. However, these tests take several minutes to report their results and are often quite conspicuous, which can pose a danger to the victim.

An anti-rape sticker

That's why a team of scientists from South Korea has developed this rapid-detection, semi-permanent tattoo for GHB that is applied to the skin like a sticker.

To create these stickers, researchers placed a mold over a thin plastic film decorated with designs similar to commercial tattoos, so as not to arouse suspicion.

Into this same container, they poured a gel mixture containing a liquid receptor that turned red when it detected GHB. They then coated the back of the sticker with a diluted glue solution so it could adhere to the skin.

Scientists tested the sticker's ability to detect small amounts of this liquid ecstasy in several common beverages: whiskey, vodka, beer, soju (a Korean alcoholic beverage), and coffee.

In just one second, the temporary tattoo detected the drug across a range of concentrations, and below a level that would lead to severe physiological symptoms: 0.01 micrograms of GHB in 1 milliliter of drink.

"In practice, the user could dip a finger into a drink , touch the drop to the sticker, and see the result in real time," the authors note.

How long does the result last?

The durability and stability of these temporary tattoos were evaluated through mechanical testing (twisting, stretching), environmental exposure (water resistance), and practical handling conditions (adhesion strength and scratch resistance).

The tattoo shows a positive result up to 30 days after detection, which could be important if needed as evidence of tampering.

The researchers claim their sticker technology is cheap and easy to manufacture and could soon be commercialized. Furthermore, it will go unnoticed by mimicking existing popular tattoo designs.

This study was funded by the National Research Foundation of Korea, the National Council of Scientific and Technological Research of Korea, the Ministry of Food and Drug Safety, and the National Center for Nanofabrication of Korea.

Do you want to receive the best content to take care of your health and feel good? Sign up for our free newsletter.