{"id":19726,"date":"2021-01-26T05:39:00","date_gmt":"2021-01-25T23:54:00","guid":{"rendered":"https:\/\/www.revoscience.com\/en\/?p=19726"},"modified":"2021-01-25T22:48:53","modified_gmt":"2021-01-25T17:03:53","slug":"materials-coloured-like-a-peacock","status":"publish","type":"post","link":"https:\/\/www.revoscience.com\/en\/materials-coloured-like-a-peacock\/","title":{"rendered":"Materials coloured like a peacock"},"content":{"rendered":"\n

Melanin-like compounds can be precisely designed and arranged to colour materials using a mechanism similar to that found in a peacock\u2019s feathers. <\/p>\n\n\n\n

Chemist Michinari Kohri of Chiba University in Japan\u00a0reviewed<\/a>\u00a0the latest research on these \u2018melanin-mimetic materials\u2019 and their potential applications for the journal\u00a0Science and Technology of Advanced Materials.<\/em><\/p>\n\n\n\n

Materials inspired by the colour changes in a peacock\u2019s feather could lead to anti-counterfeit and sensing applications.<\/em><\/strong><\/p><\/blockquote>\n\n\n\n

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Scientists are developing materials inspired by the structural colours in a peacock\u2019s feathers.\u00a0Credit: Takashi Tsujino<\/em><\/figcaption><\/figure>\n\n\n\n

Melanin is a dark pigment that gives hair and skin its colour. It is also essential for the bright colours we see in some organisms. When light interacts with the structures of feathers, wings and shells of many organisms, like peacocks, butterflies and jewel beetles, it is scattered, appearing white. <\/p>\n\n\n\n

But when melanin is interspersed within these structures, some of the scattered light is absorbed, producing various colours. Scientists are looking for ways to mimic these so-called \u2018structural colour\u2019 changes of living organisms in synthetic materials.<\/p>\n\n\n\n

\u201cVivid structural colours can be obtained by constructing microstructures containing a light-absorbing black material made of natural or artificial melanin,\u201d says Kohri. \u201cResearch in this area is progressing rapidly worldwide.\u201d<\/p>\n\n\n\n

A leading contender is a compound called polydopamine. It is made of a material naturally found in the body, so it is biocompatible. It is also dark, so it absorbs light like melanin. Scientists found they could control polydopamine\u2019s iridescence \u2013 how much the colour changes as the angle of light hitting it shifts, similar to a peacock\u2019s feather. They achieved this by altering the particle size or by adding compounds that react to a magnetic field.<\/p>\n\n\n\n

\"\"
Melanin and melanin-like compounds absorb some of the light that is scattered from the microstructures within materials. Scientists are finding ways to control this phenomenon to give a variety of iridescent and non-iridescent colours.\u00a0Credit: Michinari Kohri<\/em><\/figcaption><\/figure>\n\n\n\n

Scientists are also investigating particles formed of a polystyrene core and a polydopamine shell. Changing the diameter of the inner core, for example, leads to different colours. Making the polydopamine shell thicker causes the particles to be less closely packed, leading to non-iridescent structural colour, which remains the same regardless of the light angle.<\/p>\n\n\n\n

Scientists have also toyed with controlling colour and angle-dependence by changing the shapes of polystyrene\/polydopamine particles, making them hollow on the inside, and adding multiple coatings to the external shell.<\/p>\n\n\n\n

Polydopamine particles are showing potential for a variety of applications. For example, they can be used as inks to dye fabrics or in cosmetics. They could help prove a product is real versus counterfeit by shifting colour with strong light, wetting, or temperature changes. Finally, scientists have found that adding these particles to rubber causes it to change colour when stretched or relaxed, which could be useful for sensing local stress and strain in bridges.<\/p>\n","protected":false},"excerpt":{"rendered":"

Melanin-like compounds can be precisely designed and arranged to colour materials using a mechanism similar to that found in a peacock\u2019s feathers. <\/p>\n","protected":false},"author":2,"featured_media":19728,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[122,17],"tags":[],"class_list":["post-19726","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-chemistry","category-research"],"featured_image_urls":{"full":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin-200x200.jpg",200,200,true],"medium":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"medium_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"1536x1536":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"2048x2048":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"ultp_layout_landscape_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"ultp_layout_landscape":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"ultp_layout_portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"ultp_layout_square":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"newspaper-x-single-post":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"newspaper-x-recent-post-big":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"newspaper-x-recent-post-list-image":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin-95x65.jpg",95,65,true],"web-stories-poster-portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",461,257,false],"web-stories-publisher-logo":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",96,54,false],"web-stories-thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/melanin.jpg",150,84,false]},"author_info":{"info":["RevoScience"]},"category_info":"Chemistry<\/a> Research<\/a>","tag_info":"Research","comment_count":"0","_links":{"self":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/19726","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/comments?post=19726"}],"version-history":[{"count":0,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/19726\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media\/19728"}],"wp:attachment":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media?parent=19726"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/categories?post=19726"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/tags?post=19726"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}