Molecular code for melanin-like materials

Scientists have long known that melanin -- the pigments that give color to skin, hair and eyes -- has numerous useful qualities, including providing protection from cancer-causing UV radiation and free radicals, but also electronic conductance, adhesiveness and the capacity to store energy.

To take advantage of these qualities, scientists across the City University of New York (CUNY) have developed a new approach for producing materials that not only mimic the properties of melanin, but also provide unprecedented control over expressing specific properties of the biopolymer, according to a paper published in the journal Science. The discovery could enable the development of cosmetic and biomedical products.

Unlike other biopolymers, such as DNA and proteins, where a direct link exists between the polymers' ordered structures and their properties, melanin is inherently disordered, so directly relating structure to function is not possible. As a result, researchers have been unable to fully exploit melanin's properties because the laboratory-based synthesis of melanin has been thwarted by the difficulty of engineering its disorderly molecular structure.

"We took advantage of simple versions of proteins -- tripeptides, consisting of just three amino acids -- to produce a range of molecular architectures with precisely controlled levels of order and disorder," said lead researcher Rein V. Ulijn, director of the Nanoscience Initiative at the Advanced Science Research Center (ASRC) at the Graduate Center, CUNY. "We were amazed to see that, upon oxidation of these peptide structures, polymeric pigments with a range of colors -- from light beige to deep brown- were formed."

Click here to read full article

Share

Please log in to post comments