基于DNA折纸模板的铁原子阵列构建及其信息加密应用

在后摩尔时代,突破原有技术极限,进行原子尺度的精准构筑,是当前的重大科学问题.DNA作为具有原子级精准度的生物大分子,能够进行程序性的分子识别,构筑原子数量与位置均严格确定的自组装结构,因此是进行原子制造的理想平台.本文提出基于DNA自组装折纸结构的精准定位能力,构筑铁原子阵列图案,并应用于对信息的加密.实验结果表明,采用类似“信息预置”的方法,铁原子成功实现在DNA折纸不同位置的高效定位,此方法还极大降低了实验工作量,非常有利于多种不同阵列图案的平行制备.利用所构建的铁原子阵列,本文发展了原子阵列DNA折纸加密技术,将密文编码为二进制并用类似盲文斑点的形式在DNA折纸上以特定图案表示,通过单分子成像手段对密文信息进行了读取,而密钥长度可高达700位以上.作为示例,成功地对普通文本及唐诗《登鹳雀楼》进行了加密,证明了此策略的通用性和实用性.

Constructions of iron atoms arrays based on DNA origami templates for cryptography applications

The fabrication of precise arrays of atoms is a key challenge at present.As a kind of biomacromolecule with strict base-pairing and programmable self-assembly ability,DNA is an idea material for directing atom positioning on predefined addresses.Here in this work,we propose the construction of iron atom arrays based on DNA origami templates and illustrate the potential applications in cryptography.First,ferrocene molecule is used as the carrier for iron atom since the cyclopentadienyl groups protect iron from being affected by the external environment.To characterize the iron atom arrays,streptavidins are labelled according to the ferrocene-modified DNA strand through biotin-streptavidin interactions.Based on atomic force microscopy scanning,ferrocene-modified single-stranded DNA sequences prove to be successfully immobilized on predefined positions on DNA origami templates with high yield.Importantly,the address information of iron atoms on origami is pre-embedded on the long scaffold,enabling the workload and cost to be lowered dramatically.In addition,the iron atom arrays can be used as the platform for constructing secure Braille-like patterns with encoded information.The origami assembly and pattern characterizations are defined as encryption process and readout process,respectively.The ciphertext can be finally decoded with the secure key.This method enables the theoretical key size of more than 700 bits to be realized.Encryption and decryption of plain text and a Chinese Tang poem prove the versatility and feasibility of this strategy.