Insect cells could create everlasting paints
Long-lasting, cheap and environmentally friendly paints could be on the way after scientists manufacture unique colour cells from butterflies for the first time.
The paints could be used to make cars that stay shiny forever, make-up that never fades and clothes that never lose their colour.
The vibrant colours you see in a butterfly’s wings are the result of a phenomenon known as structural colouration. Their wings are made up of transparent scales that have intricate shapes. The scales scatter light when it hits them, creating brilliant colours that look different from different angles.
Everyday objects are traditionally coloured using dyes and pigments, which fade over time, whereas objects using structural colouration could retain their vibrancy forever.
Museum researcher Prof Andrew Parker and Dr Helen Townley of Oxford University successfully grew a butterfly wing in the lab so that it had the right structure to produce colour. Prof Parker specialises in biomimetics, the imitation of nature’s structures and materials to solve human problems.
The cells that the team cultured in the lab to produce the wing were from the blue morpho butterfly, Morpho peleides, a striking tropical species that frightens potential predators by flashing its electric blue wings.
'These scales have desirable properties for industry, but are at present too challenging to make,' said Prof Parker.
Artificial structural colouration cells have previously been produced, but they are less intricate and the process is costly and slow. Mass-producing natural structural colouration from insect cells could be a cheaper and faster alternative.
As well as being cheaper to produce, materials that use the colours created by cells would be much more environmentally friendly than traditional dyes and paints that can release toxins into the environment.
Borrowing from nature
The team cultured butterfly cells into a full wing of reflective scales. But during the process of converting cells to scales, part of the original cell was lost, so that the cells couldn’t be used to produce more scales.
This means that butterfly wing cells are not suitable for mass-producing everlasting colours, but Prof Parker believes that this could be possible with cells from other organisms, such as beetles.
Beetles such as the weevil Metapocyrtus sp., which is found in New Guinea and Australia, also display structural colouration, but their colour is achieved using a different kind of cell to the blue morpho.
The material the weevil uses to create the optical effect of structural colouration is the same as that found in the gemstone opal, and can be made in any colour.
Prof Parker hopes to apply the technique used on the butterfly wing to weevils’ cells, which are capable of producing an endless amount of colourant. With a sufficient supply of nutrients and growth hormones, weevil cells could be used to make industrial quantities of everlasting paint.