23-Feb-2023 - American Chemical Society (ACS)

Carrots: Good for your eyes … and for degradable polymers

Researchers have incorporated a compound derived from β-carotene into a polymer that’s fully degradable

Carrots come in a rainbow of bright colors — red, orange, yellow and purplish black — because of compounds called carotenoids. They help support eye health by reacting with potentially harmful UV light. Interestingly, the molecular structures of carotenoids, such as β-carotene, are similar to the building blocks of some polymers. Now, researchers reporting in the Journal of the American Chemical Society have incorporated a compound derived from β-carotene into a polymer that’s fully degradable.

Polymers and plastics formed from natural, biodegradable ingredients are highly desired for use in consumer products. By using indigo, vanillin and melanin, scientists have created biobased polymers that have electrically conductive properties that are attractive for energy storage, biomedical and sensor applications. Carotenoids are another set of natural compounds expected to transfer charges, but they haven’t been widely tested in polymer design. Another possible benefit is that these compounds break apart in the presence of UV light and certain chemicals. So, Azalea Uva, Angela Lin and Helen Tran wanted to use a carotenoid-sourced compound to make a degradable material that could be selectively broken down with an acid and sunlight.

The researchers combined the carotenoid derived from β-carotene, a 10-carbon dialdehyde, and p-phenylenediamines, a group of compounds used in degradable polymers, to make three different poly(azomethine)s. When dried, the resulting materials ranged in color from black to bright red.

In initial experiments, the team determined that the bright red version — created with p-phenylenediamine containing two hexyl side chains — was the best candidate to test further. The material completely broke down into its original components in acidic solutions, which could potentially be recovered. However, when both acid and artificial sunlight were used, this process sped up. And after an extended period of time, the sample broke down even further into smaller dialdehydes and other compounds. The next step is to evaluate this new fully degradable polymer’s ability to conduct electricity, the researchers say.

Facts, background information, dossiers
  • biodegradable polymers
  • biodegradable materials
More about American Chemical Society
  • News

    New starchy bioplastic could make soggy paper straws a thing of the past

    In the fight against pollution, several regions in the U.S. have banned the use of plastic straws. Alternative materials exist, but most options are either too expensive to scale up, go limp in drinks or taste bad. But now, a team reporting in ACS Omega has developed a new type of bioplasti ... more

    Toilet paper is an unexpected source of PFAS in wastewater

    Wastewater can provide clues about a community’s infectious disease status, and even its prescription and illicit drug use. But looking at sewage also provides information on persistent and potentially harmful compounds, such as per- and polyfluoroalkyl substances (PFAS), that get released ... more

    Are your strawberries bland? Pesticides could be to blame

    Have you ever bitten into a plump, red strawberry, only to find it bland and watery? Certain pesticides might be responsible. A team reporting in ACS’ Journal of Agricultural and Food Chemistry has found that two common strawberry fungicides can impact cellular mechanisms, creating berries ... more

  • Videos

    What Makes Rubber Rubbery?

    Reactions is looking at sports science today. Sports balls owe their reliability to an unusual polymer. Learn about the chemistry of rubber the all-star’s best friend! more

    Why is Olive Oil Awesome?

    Whether you sop it up with bread or use it to boost your cooking, olive oil is awesome. But a lot of chemistry goes on in that bottle that can make or break a product. Take the “extra virgin” standard: Chemistry tells us that a higher free-fatty-acid content leads to a lower grade, less tas ... more

    Detecting nerve agents with the touch of a finger

    There’s a reason why farmers wear protective gear when applying organophosphate pesticides. The substances are nerve agents that are very effective at getting rid of unwanted bugs, but they can also make humans sick. Even more potent, related compounds -- organophophate nerve agents -- are ... more

  • Associations

    American Chemical Society (ACS)

    The American Chemical Society is a nonprofit organization chartered by the U.S. Congress. With more than 163,000 members, ACS is the world’s largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journal ... more