Nature：分子纳米机器人新突破

zylucky98

# Y! z5 J/ j% A) n% h! i& {* F: t; d9 T8 c8 S  y$ u2 G
Nature：分子纳米机器人新突破生物谷
! e% o$ I" O0 O& T6 s& m  i3 _$ ?
( s6 q. {4 }# I来自南京大学和美国纽约大学的两个小组报告了在研制能够在分子尺度上做有用工作的可编程“纳米机器人”方面所取得的显着进展。- o3 m* a3 Q0 W+ T' I

  ^- O* t' k& m9 A较大的机器人需要一个记忆装置来存放指令，但这些小机器人却是从它们环境中的分子接受指令的。2 u  b, g! u* h2 ^: W/ A- ]$ }

& z6 Y- B8 `) p8 f两个体系都利用了最近几年开发出的两个重要DNA模块：一个是沿DNA轨道行走的DNA“行走者”；另一个是“DNA折纸”。! Y" q7 T1 D$ L
# j4 n* L5 U3 v* B( N9 E
Gu等人演示了一个微型组装线，它能通过将三种不同类型的金纳米颗粒结合起来制造8种可能的复合物。一个“DNA折纸”砖是这个生产线的框架和轨道，一个有三只手、四只脚的“DNA行走者”沿这个轨道行走，生成最终产品，其方式是：在它通过三种不同的载货DNA机器时将所收集的金纳米颗粒连接起来。Lund等人演示的纳米机器人是蜘蛛形状的DNA“行走者”，它们能在一个二维“DNA折纸”景观中感应和改动基质分子轨道，这个景观通过编程来让“行走者”执行诸如“开始”、“跟随”、“转弯”和“停止”等动作。（生物谷Bioon.com）
+ ?& G; {. T* Y1 H2 f5 X( t
3 d; s4 A1 ]6 K  E) R  q8 ^/ d原文出处：9 a  `( x% l" H3 P, I( r- [6 A

' }* j) K6 M( S  V: J# b8 ONature doi:10.1038/nature09026; }5 w% ^2 r! U# M

4 \/ P: t" h; E2 U. z6 h, ^) i1 OA proximity-based programmable DNA nanoscale assembly line
; u" [7 H& S0 Z0 s2 XHongzhou Gu1, Jie Chao2, Shou-Jun Xiao2 & Nadrian C. Seeman1
7 K: H9 B$ R% R2 F( H* n# Q7 u( X0 o- F/ c; D
1 Department of Chemistry, New York University, New York, New York 10003, USA4 s: k$ J% Q8 g* ^  N: }% E
2 State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093, China/ Z7 Z$ `% I' c6 Q# b

+ }0 C4 f/ r- jOur ability to synthesize nanometre-scale chemical species, such as nanoparticles with desired shapes and compositions, offers the exciting prospect of generating new functional materials and devices by combining them in a controlled fashion into larger structures. Self-assembly can achieve this task efficiently, but may be subject to thermodynamic and kinetic limitations: reactants, intermediates and products may collide with each other throughout the assembly time course to produce non-target species instead of target species. An alternative approach to nanoscale assembly uses information-containing molecules such as DNA1 to control interactions and thereby minimize unwanted cross-talk between different components. In principle, this method should allow the stepwise and programmed construction of target products by linking individually selected nanoscale components—much as an automobile is built on an assembly line. Here we demonstrate that a nanoscale assembly line can be realized by the judicious combination of three known DNA-based modules: a DNA origami2 tile that provides a framework and track for the assembly process, cassettes containing three independently controlled two-state DNA machines that serve as programmable cargo-donating devices3, 4 and are attached4, 5 in series to the tile, and a DNA walker that can move on the track from device to device and collect cargo. As the walker traverses the pathway prescribed by the origami tile track, it sequentially encounters the three DNA devices, each of which can be independently switched between an ‘ON’ state, allowing its cargo to be transferred to the walker, and an ‘OFF’ state, in which no transfer occurs. We use three different types of gold nanoparticle species as cargo and show that the experimental system does indeed allow the controlled fabrication of the eight different products that can be obtained with three two-state devices.