{"id":3179,"date":"2015-11-04T17:15:28","date_gmt":"2015-11-04T17:15:28","guid":{"rendered":"http:\/\/www.kurzweilai.net\/?p=266138"},"modified":"2015-11-05T18:19:37","modified_gmt":"2015-11-05T18:19:37","slug":"a-new-3-d-printing-method-for-creating-patient-specific-medical-devices","status":"publish","type":"post","link":"https:\/\/hoo.central12.com\/fugic\/2015\/11\/04\/a-new-3-d-printing-method-for-creating-patient-specific-medical-devices\/","title":{"rendered":"A new 3-​​D printing method for creating patient-​​specific medical devices"},"content":{"rendered":"
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The 3D magnetic printing process systematically aligns and selectively polymerizes groupings of voxels (volume “pixels”) programmed to have specific reinforcement orientation within each layer of printed material based upon a shifting field. The 3-D printer build plate peels after a layer is complete to print additional layers. (credit: Joshua J. Martin et al.\/Nature Communications)<\/p><\/div>\n

Northeastern University engineers have devel\u00adoped a 3-D printing process that uses mag\u00adnetic fields to shape com\u00adposite materials (mixes of plas\u00adtics and ceramics) into patient-specific biomedical devices, such as catheters.<\/p>\n

The devices are intended to be stronger and lighter than cur\u00adrent models and the cus\u00adtomized design could ensure an appro\u00adpriate fit, said Ran\u00addall Erb<\/a>,\u00a0assis\u00adtant pro\u00adfessor in the\u00a0Depart\u00adment of Mechan\u00adical and Indus\u00adtrial Engi\u00adneering<\/a>.<\/strong><\/p>\n

The magnetic field enables the engineers to con\u00adtrol how the ceramic fibers are arranged, allowing for con\u00adtrol of the mechan\u00adical prop\u00ader\u00adties of the mate\u00adrial. That con\u00adtrol is crit\u00adical if you\u2019re crafting devices with com\u00adplex archi\u00adtec\u00adtures, such as cus\u00adtomized minia\u00adture bio\u00admed\u00adical devices. Within a single patient-specific device, the cor\u00adners, the curves, and the holes must all be rein\u00adforced by ceramic fibers arranged in just the right con\u00adfig\u00adu\u00adra\u00adtion to make the device durable.<\/p>\n

This is the strategy taken by many nat\u00adural com\u00adpos\u00adites from bones to\u00a0trees. Fibers of cal\u00adcium phos\u00adphate, the min\u00aderal com\u00adpo\u00adnent of bone, are nat\u00adu\u00adrally ori\u00adented precisely around the holes for blood ves\u00adsels to ensure the bone\u2019s strength and sta\u00adbility to enable, say, your femur to with\u00adstand a daily\u00a0jog.<\/p>\n

Aligning fibers with magnets<\/strong><\/p>\n

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The 3D magnetic-printer setup. A digital light processor (DLP) photo-polymerizes resin with UV while a magnetic field is simultaneously applied via electromagnetic solenoids. (credit: Joshua J. Martin et al.\/Nature Communications)<\/p><\/div>\n

Erb ini\u00adtially described the role of magnets in the composite-making process in a 2012\u00a0paper<\/a>\u00a0in the journal\u00a0Sci\u00adence.\u00a0<\/em>First the researchers \u201cmag\u00adne\u00adtize\u201d the ceramic fibers by dusting them very lightly with iron oxide, which has been FDA-approved for drug-delivery appli\u00adca\u00adtions.<\/p>\n

They then apply ultra-low mag\u00adnetic fields to indi\u00advidual sec\u00adtions of the com\u00adposite material — the ceramic fibers immersed in liquid plastic — to align the fibers according to the exacting spec\u00adi\u00adfi\u00adca\u00adtions dic\u00adtated by the product they are printing.<\/p>\n

In a\u00a0video<\/a>\u00a0accom\u00adpa\u00adnying the\u00a0Sci\u00adence<\/em>\u00a0article, you can see the fibers spring to atten\u00adtion when the mag\u00adnetic field is turned on. \u201cMag\u00adnetic fields are very easy to apply,\u201d says Erb. \u201cThey\u2019re safe, and they pen\u00ade\u00adtrate not only our bodies but many other materials.\u201d<\/p>\n

Finally, in a process called \u201cstere\u00adolith\u00ado\u00adg\u00adraphy,\u201d they build the product, layer by layer, using a computer-controlled laser beam that hardens the plastic. Each six-by-six inch layer takes a minute to complete.<\/p>\n

Using mag\u00adnets, the new printing method aligns each minus\u00adcule fiber in the direc\u00adtion that con\u00adforms pre\u00adcisely to the geom\u00adetry of the item being\u00a0printed.<\/p>\n

\u201cIf you can print a catheter whose geom\u00adetry is spe\u00adcific to the indi\u00advidual patient, you can insert it up to a cer\u00adtain crit\u00adical spot, you can avoid punc\u00adturing veins, and you can expe\u00addite delivery of the contents.\u201d<\/p>\n

The engineers’ open-access paper<\/a>\u00a0on the new tech\u00adnology appears in the Oct. 23 issue of\u00a0Nature Com\u00admu\u00adni\u00adca\u00adtions. <\/em><\/p>\n

Custom-designing neonatal catheters<\/strong><\/p>\n

Erb <\/strong>has received a $225,000 Small Busi\u00adness Tech\u00adnology Transfer grant from the National Institutes of Health to develop neonatal catheters with a local com\u00adpany. \u201cAnother of our goals is to use cal\u00adcium phos\u00adphate fibers and bio\u00adcom\u00adpat\u00adible plas\u00adtics to design sur\u00adgical implants.\u201d<\/p>\n

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Neonatal preemie with catheters (credit: March of Dimes Foundation)<\/p><\/div>\n

The new technology is especially valuable for prema\u00adture babies (“preemies”) in neonatal care units, some weighing just a bit over a pound, with plastic tubes snaking through their nose or mouth, or dis\u00adap\u00adpearing into veins or other parts of the body. Those tubes, or \u201ccatheters,\u201d are how the babies get the nec\u00ades\u00adsary oxygen, nutri\u00adents, fluid, and med\u00adica\u00adtions to stay alive.<\/p>\n

The problem is, today\u2019s catheters only come in stan\u00addard sizes and shapes, which means they cannot accom\u00admo\u00addate the needs of all pre\u00adma\u00adture babies. \u201cWith neonatal care, each baby is a dif\u00adferent size, each baby has a dif\u00adferent set of prob\u00adlems,\u201d says Erb.<\/p>\n

Worldwide, “15 million babies are born too soon every year” and of those, “1 million children die each year due to complications of preterm birth,” according to a report<\/a> by the World Health Organization. This data was cited in the “March of Dimes Premature Birth Report Card<\/a>,” issued today (Nov. 5) by March of Dimes. “Babies who survive an early birth often face serious and lifelong health problems, including breathing problems, jaundice, vision loss, cerebral palsy, and intellectual delays,” the March of Dimes report noted.<\/p>\n

The report provides rates and grades for major cities or counties in each U.S. state and Puerto Rico. It also provides preterm birth rates by race and ethnicity. The U.S. preterm birth rate ranks among the worst of high-resource countries, the March of Dimes says.<\/p>\n

\n

Abstract of\u00a0Designing bioinspired composite reinforcement architectures via 3D magnetic printing<\/em><\/strong><\/p>\n

Discontinuous fibre composites represent a class of materials that are strong, lightweight and have remarkable fracture toughness. These advantages partially explain the abundance and variety of discontinuous fibre composites that have evolved in the natural world. Many natural structures out-perform the conventional synthetic counterparts due, in part, to the more elaborate reinforcement architectures that occur in natural composites. Here we present an additive manufacturing approach that combines real-time colloidal assembly with existing additive manufacturing technologies to create highly programmable discontinuous fibre composites. This technology, termed as \u20183D magnetic printing\u2019, has enabled us to recreate complex bioinspired reinforcement architectures that deliver enhanced material performance compared with monolithic structures. Further, we demonstrate that we can now design and evolve elaborate reinforcement architectures that are not found in nature, demonstrating a high level of possible customization in discontinuous fibre composites with arbitrary geometries.<\/p>\n","protected":false},"excerpt":{"rendered":"

Northeastern University engineers have devel­oped a 3-D printing process that uses mag­netic fields to shape com­posite materials (mixes of plas­tics and ceramics) into patient-specific biomedical devices, such as catheters. The devices are intended to be stronger and lighter than cur­rent models and the cus­tomized design could ensure an appro­priate fit, said Ran­dall Erb, assis­tant pro­fessor in […]<\/p>\n","protected":false},"author":13,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[45,48,55,43],"tags":[],"class_list":["post-3179","post","type-post","status-publish","format-standard","hentry","category-biomedlongevity","category-electronics","category-nanotechmaterials-science","category-news"],"_links":{"self":[{"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/posts\/3179"}],"collection":[{"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/users\/13"}],"replies":[{"embeddable":true,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/comments?post=3179"}],"version-history":[{"count":2,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/posts\/3179\/revisions"}],"predecessor-version":[{"id":3189,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/posts\/3179\/revisions\/3189"}],"wp:attachment":[{"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/media?parent=3179"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/categories?post=3179"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/tags?post=3179"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}