');display:flex;inset:0;justify-content:center;position:absolute}.copy-to-clipboard-button[data-copy-state=copy-success]:before{content:url('data:image/svg+xml;utf8,')}.kg-bookmark-card figcaption,.kg-gallery-card figcaption,.kg-image-card figcaption,.kg-video-card figcaption{padding-top:2px;text-align:center;--tw-text-opacity:1;color:rgb(71 85 105/var(--tw-text-opacity,1))}.kg-bookmark-card figcaption:is(.dark *),.kg-gallery-card figcaption:is(.dark *),.kg-image-card figcaption:is(.dark *),.kg-video-card figcaption:is(.dark *){--tw-text-opacity:1;color:rgb(203 213 225/var(--tw-text-opacity,1))}.kg-code-card figcaption{padding-top:2px;text-align:center;--tw-text-opacity:1;color:rgb(71 85 105/var(--tw-text-opacity,1))}.kg-code-card figcaption:is(.dark *){--tw-text-opacity:1;color:rgb(15 23 42/var(--tw-text-opacity,1))}.toc{overflow-y:auto}.toc>.toc-list{overflow:hidden;position:relative}.toc>.toc-list li{list-style:none}.js-toc{overflow-y:hidden}.toc-list{margin:0;padding-left:1.5rem}a.toc-link{color:currentColor;height:100%}.is-collapsible{max-height:1000px;overflow:hidden;transition:all .3s ease-in-out}.is-collapsed{max-height:0}.is-position-fixed{position:fixed!important;top:0}.is-active-link{font-weight:700}.toc-link:before{background-color:#eee;content:" ";display:inline-block;height:inherit;left:0;margin-top:-1px;position:absolute;width:2px}.is-active-link:before{background-color:#54bc4b}.toc-list-item{font-size:.95rem;margin-bottom:.5rem}.toc-link{border-radius:.25rem;color:#333;display:block;padding:.25rem .5rem;text-decoration:none;transition:color .2s ease}.toc-link:hover{background-color:#f3f4f6;color:#1e40af}.toc-link.is-active-link{background-color:#e0e7ff;color:#1e40af;font-weight:600}.toc-link.node-name--H2{font-size:1rem}.content img[width="20"],.content img[width="25"]{display:inline;margin-left:.25rem;margin-right:.25rem}.content table td[colspan="2"]{text-align:center}.content table td img{margin:auto}.first-letter\:uppercase:first-letter{text-transform:uppercase}.hover\:scale-110:hover{--tw-scale-x:1.1;--tw-scale-y:1.1;transform:translate(var(--tw-translate-x),var(--tw-translate-y)) rotate(var(--tw-rotate)) skewX(var(--tw-skew-x)) skewY(var(--tw-skew-y)) scaleX(var(--tw-scale-x)) scaleY(var(--tw-scale-y))}.hover\:border-blue-400:hover{--tw-border-opacity:1;border-color:rgb(96 165 250/var(--tw-border-opacity,1))}.hover\:border-secondary-300:hover{--tw-border-opacity:1;border-color:rgb(203 213 225/var(--tw-border-opacity,1))}.hover\:bg-blue-700:hover{--tw-bg-opacity:1;background-color:rgb(29 78 216/var(--tw-bg-opacity,1))}.hover\:bg-gray-100:hover{--tw-bg-opacity:1;background-color:rgb(243 244 246/var(--tw-bg-opacity,1))}.hover\:bg-gray-50:hover{--tw-bg-opacity:1;background-color:rgb(249 250 251/var(--tw-bg-opacity,1))}.hover\:bg-primary-100:hover{--tw-bg-opacity:1;background-color:rgb(224 242 254/var(--tw-bg-opacity,1))}.hover\:bg-primary-200:hover{--tw-bg-opacity:1;background-color:rgb(186 230 253/var(--tw-bg-opacity,1))}.hover\:bg-primary-50:hover{--tw-bg-opacity:1;background-color:rgb(240 249 255/var(--tw-bg-opacity,1))}.hover\:bg-primary-50\/80:hover{background-color:rgba(240,249,255,.8)}.hover\:bg-primary-700:hover{--tw-bg-opacity:1;background-color:rgb(29 78 216/var(--tw-bg-opacity,1))}.hover\:bg-red-100:hover{--tw-bg-opacity:1;background-color:rgb(254 226 226/var(--tw-bg-opacity,1))}.hover\:bg-secondary-100:hover{--tw-bg-opacity:1;background-color:rgb(241 245 249/var(--tw-bg-opacity,1))}.hover\:from-blue-600:hover{--tw-gradient-from:#2563eb var(--tw-gradient-from-position);--tw-gradient-to:rgba(37,99,235,0) var(--tw-gradient-to-position);--tw-gradient-stops:var(--tw-gradient-from),var(--tw-gradient-to)}.hover\:to-blue-700:hover{--tw-gradient-to:#1d4ed8 var(--tw-gradient-to-position)}.hover\:text-accent-600:hover{--tw-text-opacity:1;color:rgb(217 119 6/var(--tw-text-opacity,1))}.hover\:text-blue-600:hover{--tw-text-opacity:1;color:rgb(37 99 235/var(--tw-text-opacity,1))}.hover\:text-blue-800:hover{--tw-text-opacity:1;color:rgb(30 64 175/var(--tw-text-opacity,1))}.hover\:text-gray-400:hover{--tw-text-opacity:1;color:rgb(156 163 175/var(--tw-text-opacity,1))}.hover\:text-gray-700:hover{--tw-text-opacity:1;color:rgb(55 65 81/var(--tw-text-opacity,1))}.hover\:text-green-600:hover{--tw-text-opacity:1;color:rgb(22 163 74/var(--tw-text-opacity,1))}.hover\:text-primary-600:hover{--tw-text-opacity:1;color:rgb(37 99 235/var(--tw-text-opacity,1))}.hover\:text-primary-700:hover{--tw-text-opacity:1;color:rgb(29 78 216/var(--tw-text-opacity,1))}.hover\:text-secondary-700:hover{--tw-text-opacity:1;color:rgb(51 65 85/var(--tw-text-opacity,1))}.hover\:opacity-90:hover{opacity:.9}.hover\:shadow-lg:hover{--tw-shadow:0 10px 15px -3px rgba(0,0,0,.1),0 4px 6px -4px rgba(0,0,0,.1);--tw-shadow-colored:0 10px 15px -3px var(--tw-shadow-color),0 4px 6px -4px var(--tw-shadow-color);box-shadow:var(--tw-ring-offset-shadow,0 0 #0000),var(--tw-ring-shadow,0 0 #0000),var(--tw-shadow)}.focus\:border-transparent:focus{border-color:transparent}.focus\:bg-primary-50:focus{--tw-bg-opacity:1;background-color:rgb(240 249 255/var(--tw-bg-opacity,1))}.focus\:text-primary-600:focus{--tw-text-opacity:1;color:rgb(37 99 235/var(--tw-text-opacity,1))}.focus\:outline-none:focus{outline:2px solid transparent;outline-offset:2px}.focus\:ring-1:focus{--tw-ring-offset-shadow:var(--tw-ring-inset) 0 0 0 var(--tw-ring-offset-width) var(--tw-ring-offset-color);--tw-ring-shadow:var(--tw-ring-inset) 0 0 0 calc(1px + var(--tw-ring-offset-width)) var(--tw-ring-color);box-shadow:var(--tw-ring-offset-shadow),var(--tw-ring-shadow),var(--tw-shadow,0 0 #0000)}.focus\:ring-blue-500:focus{--tw-ring-opacity:1;--tw-ring-color:rgb(59 130 246/var(--tw-ring-opacity,1))}.focus\:ring-gray-500:focus{--tw-ring-opacity:1;--tw-ring-color:rgb(107 114 128/var(--tw-ring-opacity,1))}.focus\:ring-offset-2:focus{--tw-ring-offset-width:2px}.group:focus-within .group-focus-within\:opacity-100{opacity:1}.group:hover .group-hover\:visible,.group\/level2:hover .group-hover\/level2\:visible{visibility:visible}.group:hover .group-hover\:block{display:block}.group\/item:hover .group-hover\/item\:translate-x-1{--tw-translate-x:0.25rem}.group\/item:hover .group-hover\/item\:translate-x-1,.group\/level2:hover .group-hover\/level2\:translate-x-0{transform:translate(var(--tw-translate-x),var(--tw-translate-y)) rotate(var(--tw-rotate)) skewX(var(--tw-skew-x)) skewY(var(--tw-skew-y)) scaleX(var(--tw-scale-x)) scaleY(var(--tw-scale-y))}.group\/level2:hover .group-hover\/level2\:translate-x-0{--tw-translate-x:0px}.group\/level2:hover .group-hover\/level2\:translate-x-1{--tw-translate-x:0.25rem}.group:hover .group-hover\:-translate-x-1,.group\/level2:hover .group-hover\/level2\:translate-x-1{transform:translate(var(--tw-translate-x),var(--tw-translate-y)) rotate(var(--tw-rotate)) skewX(var(--tw-skew-x)) skewY(var(--tw-skew-y)) scaleX(var(--tw-scale-x)) scaleY(var(--tw-scale-y))}.group:hover .group-hover\:-translate-x-1{--tw-translate-x:-0.25rem}.group:hover .group-hover\:translate-x-1{--tw-translate-x:0.25rem}.group:hover .group-hover\:rotate-180,.group:hover .group-hover\:translate-x-1{transform:translate(var(--tw-translate-x),var(--tw-translate-y)) rotate(var(--tw-rotate)) skewX(var(--tw-skew-x)) skewY(var(--tw-skew-y)) scaleX(var(--tw-scale-x)) scaleY(var(--tw-scale-y))}.group:hover .group-hover\:rotate-180{--tw-rotate:180deg}.group\/bookmark:hover .group-hover\/bookmark\:fill-current,.group\/comment:hover .group-hover\/comment\:fill-current,.group\/like:hover .group-hover\/like\:fill-current{fill:currentColor}.group:hover .group-hover\:fill-black\/75{fill:rgba(0,0,0,.75)}.group:hover .group-hover\:fill-current{fill:currentColor}.group:hover .group-hover\:text-primary-600{--tw-text-opacity:1;color:rgb(37 99 235/var(--tw-text-opacity,1))}.group:hover .group-hover\:opacity-100,.group\/level2:hover .group-hover\/level2\:opacity-100{opacity:1}.dark\:border-primary-400:is(.dark *){--tw-border-opacity:1;border-color:rgb(56 189 248/var(--tw-border-opacity,1))}.dark\:border-secondary-200:is(.dark *){--tw-border-opacity:1;border-color:rgb(226 232 240/var(--tw-border-opacity,1))}.dark\:border-secondary-600:is(.dark *){--tw-border-opacity:1;border-color:rgb(71 85 105/var(--tw-border-opacity,1))}.dark\:border-secondary-700:is(.dark *){--tw-border-opacity:1;border-color:rgb(51 65 85/var(--tw-border-opacity,1))}.dark\:bg-blue-900\/20:is(.dark *){background-color:rgba(30,58,138,.2)}.dark\:bg-gray-800:is(.dark *){--tw-bg-opacity:1;background-color:rgb(31 41 55/var(--tw-bg-opacity,1))}.dark\:bg-gray-800\/95:is(.dark *){background-color:rgba(31,41,55,.95)}.dark\:bg-gray-900:is(.dark *){--tw-bg-opacity:1;background-color:rgb(17 24 39/var(--tw-bg-opacity,1))}.dark\:bg-gray-900\/80:is(.dark *){background-color:rgba(17,24,39,.8)}.dark\:bg-primary-900:is(.dark *){--tw-bg-opacity:1;background-color:rgb(30 58 138/var(--tw-bg-opacity,1))}.dark\:bg-secondary-700:is(.dark *){--tw-bg-opacity:1;background-color:rgb(51 65 85/var(--tw-bg-opacity,1))}.dark\:bg-secondary-800:is(.dark *){--tw-bg-opacity:1;background-color:rgb(30 41 59/var(--tw-bg-opacity,1))}.dark\:bg-secondary-900:is(.dark *){--tw-bg-opacity:1;background-color:rgb(15 23 42/var(--tw-bg-opacity,1))}.dark\:bg-slate-400:is(.dark *){--tw-bg-opacity:1;background-color:rgb(148 163 184/var(--tw-bg-opacity,1))}.dark\:fill-white\/60:is(.dark *){fill:hsla(0,0%,100%,.6)}.dark\:fill-white\/70:is(.dark *){fill:hsla(0,0%,100%,.7)}.dark\:stroke-white\/60:is(.dark *){stroke:hsla(0,0%,100%,.6)}.dark\:text-\[rgba\(255\2c 255\2c 255\2c 0\.5\)\]:is(.dark *){color:hsla(0,0%,100%,.5)}.dark\:text-blue-400:is(.dark *){--tw-text-opacity:1;color:rgb(96 165 250/var(--tw-text-opacity,1))}.dark\:text-gray-100:is(.dark *){--tw-text-opacity:1;color:rgb(243 244 246/var(--tw-text-opacity,1))}.dark\:text-gray-200:is(.dark *){--tw-text-opacity:1;color:rgb(229 231 235/var(--tw-text-opacity,1))}.dark\:text-gray-300:is(.dark *){--tw-text-opacity:1;color:rgb(209 213 219/var(--tw-text-opacity,1))}.dark\:text-gray-400:is(.dark *){--tw-text-opacity:1;color:rgb(156 163 175/var(--tw-text-opacity,1))}.dark\:text-primary-400:is(.dark *){--tw-text-opacity:1;color:rgb(56 189 248/var(--tw-text-opacity,1))}.dark\:text-secondary-100:is(.dark *){--tw-text-opacity:1;color:rgb(241 245 249/var(--tw-text-opacity,1))}.dark\:text-secondary-300:is(.dark *){--tw-text-opacity:1;color:rgb(203 213 225/var(--tw-text-opacity,1))}.dark\:text-secondary-400:is(.dark *){--tw-text-opacity:1;color:rgb(148 163 184/var(--tw-text-opacity,1))}.dark\:text-secondary-600:is(.dark *){--tw-text-opacity:1;color:rgb(71 85 105/var(--tw-text-opacity,1))}.dark\:text-slate-200:is(.dark *){--tw-text-opacity:1;color:rgb(226 232 240/var(--tw-text-opacity,1))}.dark\:text-white:is(.dark *){--tw-text-opacity:1;color:rgb(255 255 255/var(--tw-text-opacity,1))}.dark\:shadow-gray-800\/50:is(.dark *){--tw-shadow-color:rgba(31,41,55,.5);--tw-shadow:var(--tw-shadow-colored)}.dark\:shadow-gray-900\/50:is(.dark *){--tw-shadow-color:rgba(17,24,39,.5);--tw-shadow:var(--tw-shadow-colored)}.dark\:ring-gray-700:is(.dark *){--tw-ring-opacity:1;--tw-ring-color:rgb(55 65 81/var(--tw-ring-opacity,1))}.dark\:ring-secondary-600:is(.dark *){--tw-ring-opacity:1;--tw-ring-color:rgb(71 85 105/var(--tw-ring-opacity,1))}.dark\:hover\:border-secondary-600:hover:is(.dark *){--tw-border-opacity:1;border-color:rgb(71 85 105/var(--tw-border-opacity,1))}.dark\:hover\:bg-gray-700:hover:is(.dark *){--tw-bg-opacity:1;background-color:rgb(55 65 81/var(--tw-bg-opacity,1))}.dark\:hover\:bg-gray-700\/80:hover:is(.dark *){background-color:rgba(55,65,81,.8)}.dark\:hover\:bg-gray-800:hover:is(.dark *){--tw-bg-opacity:1;background-color:rgb(31 41 55/var(--tw-bg-opacity,1))}.dark\:hover\:bg-secondary-700:hover:is(.dark *){--tw-bg-opacity:1;background-color:rgb(51 65 85/var(--tw-bg-opacity,1))}.dark\:hover\:text-accent-400:hover:is(.dark *){--tw-text-opacity:1;color:rgb(251 191 36/var(--tw-text-opacity,1))}.dark\:hover\:text-gray-200:hover:is(.dark *){--tw-text-opacity:1;color:rgb(229 231 235/var(--tw-text-opacity,1))}.dark\:hover\:text-green-400:hover:is(.dark *){--tw-text-opacity:1;color:rgb(74 222 128/var(--tw-text-opacity,1))}.dark\:hover\:text-primary-300:hover:is(.dark *){--tw-text-opacity:1;color:rgb(125 211 252/var(--tw-text-opacity,1))}.dark\:hover\:text-primary-400:hover:is(.dark *){--tw-text-opacity:1;color:rgb(56 189 248/var(--tw-text-opacity,1))}.dark\:hover\:text-secondary-300:hover:is(.dark *){--tw-text-opacity:1;color:rgb(203 213 225/var(--tw-text-opacity,1))}.dark\:focus\:bg-gray-700:focus:is(.dark *){--tw-bg-opacity:1;background-color:rgb(55 65 81/var(--tw-bg-opacity,1))}.dark\:focus\:bg-gray-800:focus:is(.dark *){--tw-bg-opacity:1;background-color:rgb(31 41 55/var(--tw-bg-opacity,1))}.dark\:focus\:text-primary-400:focus:is(.dark *){--tw-text-opacity:1;color:rgb(56 189 248/var(--tw-text-opacity,1))}.dark\:focus\:ring-offset-gray-800:focus:is(.dark *){--tw-ring-offset-color:#1f2937}.dark\:focus\:ring-offset-gray-900:focus:is(.dark *){--tw-ring-offset-color:#111827}.dark\:focus\:ring-offset-secondary-800:focus:is(.dark *){--tw-ring-offset-color:#1e293b}.dark\:focus\:ring-offset-secondary-900:focus:is(.dark *){--tw-ring-offset-color:#0f172a}.group:hover .dark\:group-hover\:fill-white\/75:is(.dark *){fill:hsla(0,0%,100%,.75)}.group:hover .dark\:group-hover\:text-primary-400:is(.dark *){--tw-text-opacity:1;color:rgb(56 189 248/var(--tw-text-opacity,1))}@media (min-width:640px){.sm\:col-span-1{grid-column:span 1/span 1}.sm\:mx-1{margin-left:.25rem;margin-right:.25rem}.sm\:mx-2{margin-left:.5rem;margin-right:.5rem}.sm\:inline{display:inline}.sm\:max-w-screen-sm{max-width:640px}.sm\:grid-cols-2{grid-template-columns:repeat(2,minmax(0,1fr))}.sm\:p-8{padding:2rem}.sm\:px-5{padding-left:1.25rem;padding-right:1.25rem}.sm\:px-6{padding-left:1.5rem;padding-right:1.5rem}.sm\:px-8{padding-left:2rem;padding-right:2rem}.sm\:py-10{padding-bottom:2.5rem;padding-top:2.5rem}.sm\:py-3{padding-bottom:.75rem;padding-top:.75rem}}@media (min-width:768px){.md\:col-span-1{grid-column:span 1/span 1}.md\:h-14{height:3.5rem}.md\:h-96{height:24rem}.md\:w-14{width:3.5rem}.md\:grid-cols-2{grid-template-columns:repeat(2,minmax(0,1fr))}.md\:grid-cols-4{grid-template-columns:repeat(4,minmax(0,1fr))}.md\:flex-row{flex-direction:row}.md\:text-4xl{font-size:2.25rem;line-height:2.5rem}}@media (min-width:1024px){.lg\:invisible{visibility:hidden}.lg\:absolute{position:absolute}.lg\:left-0{left:0}.lg\:col-span-1{grid-column:span 1/span 1}.lg\:col-span-2{grid-column:span 2/span 2}.lg\:col-span-3{grid-column:span 3/span 3}.lg\:row-span-3{grid-row:span 3/span 3}.lg\:row-span-4{grid-row:span 4/span 4}.lg\:row-span-6{grid-row:span 6/span 6}.lg\:mt-2{margin-top:.5rem}.lg\:block{display:block}.lg\:inline{display:inline}.lg\:flex{display:flex}.lg\:hidden{display:none}.lg\:h-\[496px\]{height:496px}.lg\:w-48{width:12rem}.lg\:grid-cols-3{grid-template-columns:repeat(3,minmax(0,1fr))}.lg\:grid-cols-4{grid-template-columns:repeat(4,minmax(0,1fr))}.lg\:grid-cols-5{grid-template-columns:repeat(5,minmax(0,1fr))}.lg\:grid-cols-\[auto_1fr_auto\]{grid-template-columns:auto 1fr auto}.lg\:flex-row{flex-direction:row}.lg\:items-center{align-items:center}.lg\:gap-2{gap:.5rem}.lg\:rounded-lg{border-radius:.5rem}.lg\:p-6{padding:1.5rem}.lg\:px-8{padding-left:2rem;padding-right:2rem}.lg\:py-2{padding-bottom:.5rem;padding-top:.5rem}.lg\:pl-0{padding-left:0}.lg\:text-3xl{font-size:1.875rem;line-height:2.25rem}.lg\:text-5xl{font-size:3rem;line-height:1}.lg\:opacity-0{opacity:0}.lg\:shadow-lg{--tw-shadow:0 10px 15px -3px rgba(0,0,0,.1),0 4px 6px -4px rgba(0,0,0,.1);--tw-shadow-colored:0 10px 15px -3px var(--tw-shadow-color),0 4px 6px -4px var(--tw-shadow-color);box-shadow:var(--tw-ring-offset-shadow,0 0 #0000),var(--tw-ring-shadow,0 0 #0000),var(--tw-shadow)}.lg\:ring-1{--tw-ring-offset-shadow:var(--tw-ring-inset) 0 0 0 var(--tw-ring-offset-width) var(--tw-ring-offset-color);--tw-ring-shadow:var(--tw-ring-inset) 0 0 0 calc(1px + var(--tw-ring-offset-width)) var(--tw-ring-color);box-shadow:var(--tw-ring-offset-shadow),var(--tw-ring-shadow),var(--tw-shadow,0 0 #0000)}.lg\:ring-black{--tw-ring-opacity:1;--tw-ring-color:rgb(0 0 0/var(--tw-ring-opacity,1))}.lg\:ring-opacity-5{--tw-ring-opacity:0.05}.group:focus-within .lg\:group-focus-within\:visible{visibility:visible}.group:hover .lg\:group-hover\:visible{visibility:visible}.group:hover .lg\:group-hover\:opacity-100{opacity:1}.dark\:lg\:shadow-gray-900\/50:is(.dark *){--tw-shadow-color:rgba(17,24,39,.5);--tw-shadow:var(--tw-shadow-colored)}.dark\:lg\:ring-gray-700:is(.dark *){--tw-ring-opacity:1;--tw-ring-color:rgb(55 65 81/var(--tw-ring-opacity,1))}}.gh-post-upgrade-cta{align-items:center;color:#fff;display:flex;flex-direction:column;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Open Sans,Helvetica Neue,sans-serif;font-size:16px;text-align:center;width:100%}.gh-post-upgrade-cta-content{border-radius:8px;padding:40px 4vw}.gh-post-upgrade-cta h2{color:#fff;font-size:28px;letter-spacing:-.2px;margin:0;padding:0}.gh-post-upgrade-cta p{margin:20px 0 0;padding:0}.gh-post-upgrade-cta small{font-size:16px;letter-spacing:-.2px}.gh-post-upgrade-cta a{cursor:pointer;font-weight:500}.gh-post-upgrade-cta a,.gh-post-upgrade-cta a:hover{box-shadow:none;color:#fff;text-decoration:underline}.gh-post-upgrade-cta a:hover{opacity:.8}.gh-post-upgrade-cta a.gh-btn{background:#fff;border-radius:4px;display:block;font-size:16px;font-weight:600;margin:28px 0 0;padding:8px 18px;text-decoration:none}.gh-post-upgrade-cta a.gh-btn:hover{opacity:.92}#search.loading{pointer-events:none}#search.loading i,#search.loading span,#search.loading svg{opacity:0;visibility:hidden}#search.loading:before{animation:search-loading-spin .8s linear infinite;border:3px solid rgba(0,0,0,.1);border-radius:50%;border-top-color:currentcolor;height:20px;margin:-10px 0 0 -10px;width:20px;z-index:1}#search.loading:after,#search.loading:before{content:"";left:50%;position:absolute;top:50%}#search.loading:after{animation:search-loading-pulse 1.5s ease-in-out infinite;background:rgba(0,0,0,.05);border-radius:50%;height:32px;margin:-16px 0 0 -16px;width:32px}@keyframes search-loading-spin{0%{transform:rotate(0deg)}to{transform:rotate(1turn)}}@keyframes search-loading-pulse{0%,to{opacity:.5;transform:scale(.8)}50%{opacity:.8;transform:scale(1.2)}}

德国慕尼黑工业大学近日发布一项研究成果,运用DNA 奈米技术开发出一种可吞噬并中和病毒的基因物质,目前实验已证实对肝炎病毒与腺病毒类型有显著效果,研究团队将继续实验新技术对于冠状病毒的效力。
自从1965年美国生物学家Donald Casper及英国生物物理学家Aaron Klug发现了病毒包膜(Protein Envelopes)的几何原理之后,医学及生物学界便在这项基础上不断地开发对付病毒的各种方式,但至今尚未出现像抗生素之于细菌那样广泛、有效的解方。
由慕尼黑工业大学(Technical University of Munich, TUM)物理系教授Hendrik Dietz 率领的团队,花了多年时间研发这项以奈米工程制造的DNA 物质,作为捕捉病毒的陷阱。
研究团队花费许多时间,使用DNA 折纸技术(DNA Origami),将DNA 物质塑造成一个有开口、中空的二十面体(Icosahedron),只要把与病毒相关的抗原分子整合在这个载体中,就可以透过物理机制将病毒锁在载体内进行中和,并排出体外。
「这项技术最大的挑战,在于如何稳定的做出刚好可以锁住病毒的大小。」Dietz 博士表示,先前的实验中,由于制造技术拿捏不准,总是做得太小以至于病毒塞不进去,等到克服尺寸问题后,二十面体的各个接点都需要使用斜角设计,也花费了团队许多时间掌握技术。
目前团队的病毒陷阱良率已可达95% 以上,因此他们与TUM 病毒研究所(Virology Institute)的Ulrike Protzer 教授团队共同合作,使用腺病毒与B 型肝炎病毒在实验鼠上进行动物试验。
「实验结果显示,只要尺寸正确,即便是陷阱开口比较大,都仍然能有效地困住病毒。」Dietz 教授指出,团队在陷阱中置入了五组可与病毒结合的抗原分子,就可达到80% 的病毒阻绝率,如果将陷阱中的病毒接点数量再扩充的话,应可达到完全阻绝的效果。
病毒陷阱如果成功,将会是医学领域的一大突破,对于现在流行的COVID-19(新型冠状病毒),或是将来出现的各种新病毒,都能够有效应付。
由于这项技术使用DNA 及奈米工程技术,对人体后遗症较少,且有助于制药产业大量生产压低成本,使新的病毒陷阱配方,能够像抗生素一样,为人类健康做出重大贡献。
The Virus Trap: Hollow Nano-Objects Made of DNA Could Trap Viruses and Render Them Harmless
To date, there are no effective antidotes against most virus infections. An interdisciplinary research team at the Technical University of Munich (TUM) has now developed a new approach: they engulf and neutralize viruses with nano-capsules tailored from genetic material using the DNA origami method.
SciTechDailyTechnical University of Munich (TUM)