单分散和单功能化DNA Au纳米集群,具有用于STED成像的增强光学性能
Liqing Qi1,2, Yating Xiao2,3, Xiaoyi Fu2
1Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, 300072, China.
Small (Weinheim an der Bergstrasse, Germany)
|February 22, 2024
概括
在DNA中的超小金纳米集群 (AuNCs) 为刺激排放消耗 (STED) 显微镜提供了更好的性能. 这种新的方法提高了探头的稳定性,光学特性和生物结构的成像分辨率.
科学领域:
- 纳米技术纳米技术
- 生物光子学 生物光子学
- 超高分辨率显微镜的使用方法
背景情况:
- 刺激发射耗尽 (STED) 显微镜的性能在很大程度上依赖于光探针.
- 超小金纳米集群 (AuNCs) 具有有利于STED成像的光学特性,包括大的斯托克斯转移和良好的刺激辐射响应.
- Au NCs的局限性包括多分散性,环境敏感性,以及控制表面功能化的挑战,导致标签密度和异质性差.
研究的目的:
- 通过开发一种精确的表面功能化和改进探针特性来克服STED成像的AuNCs的局限性.
- 为了提高超小AUNC的单分散性,稳定性和光学特性,用于高级显微镜应用.
主要方法:
- 在DNA中封装超小的AuNC,以实现单分散和单功能探针.
- 评估长期稳定性和光性质 (量子产量,光稳定性) 的DNA Au NCs.
- 在生物结构的STED成像中应用DNA化的AuNC,比较与未化的AuNC的性能.
主要成果:
- DNA-caging导致单分散的,长期稳定的Au NCs,显著改善光量子产量和光稳定性.
- 使用DNA化的Au NC进行STED成像,实现了大约40nm的空间分辨率,使得能够清晰地可视化具有高标签密度和同质性的微管结构.
- 开放的Au NCs-DNA合物产生了较低的分辨率 (约. 55nm) 和由于聚合而导致的分辨率差的结构.
结论:
- 一种使用DNA子的新方法精确地功能化和稳定了超小的Au NCs.
- 与传统的Au NC相比,DNA化的Au NC在STED成像中表现出优异的性能,提供了更好的分辨率和同质性.
- 这种方法为先进的超高分辨率显微镜提供了一个有前途的新类光探头.
相关概念视频
Hydroboration-Oxidation of Alkenes
In addition to the oxymercuration–demercuration method, which converts the alkenes to alcohols with Markovnikov orientation, a complementary hydroboration-oxidation method yields the anti-Markovnikov product. The hydroboration reaction, discovered in 1959 by H.C. Brown, involves the addition of a B–H bond of borane to an alkene giving an organoborane intermediate. The oxidation of this intermediate with basic hydrogen peroxide forms an alcohol.
Preparation of Alcohols via Addition Reactions
Overview
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
Acid-Catalyzed Dehydration of Alcohols to Alkenes
In a dehydration reaction, a hydroxyl group in an alcohol is eliminated along with the hydrogen from an adjacent carbon. Here, the products are an alkene and a molecule of water. Dehydration of alcohols is generally achieved by heating in the presence of an acid catalyst. While the dehydration of primary alcohols requires high temperatures and acid concentrations, secondary and tertiary alcohols can lose a water molecule under relatively mild conditions.
Oxidation of Alcohols
In this lesson, the oxidation of alcohols is discussed in depth. The various reagents used for oxidation of primary and secondary alcohols are detailed, and their mechanism of action is provided.
The process of oxidation in a chemical reaction is observed in any of the three forms:
The process of oxidation in a chemical reaction is observed in any of the three forms:
Preparation of Aldehydes and Ketones from Alcohols, Alkenes, and Alkynes
Aldehydes and ketones are prepared from alcohols, alkenes, and alkynes via different reaction pathways. Alcohols are the most commonly used substrates for synthesizing aldehydes and ketones. The conversion of alcohol to aldehyde, which involves the oxidation process, depends on the class of the alcohol used and the strength of the oxidizing agent. For instance, primary alcohol will form an aldehyde when treated with a weak oxidizing agent; however, it gets over-oxidized to a carboxylic acid in...
Reactions of Aldehydes and Ketones: Baeyer–Villiger Oxidation
Baeyer–Villiger oxidation converts aldehydes to carboxylic acids and ketones to esters. The reaction uses peroxy acids or peracids and is often catalyzed by acid. The reaction is named after its pioneers, Adolf von Baeyer and Victor Villiger. The reaction is achieved by a wide range of peracids such as m-chloroperoxybenzoic acid (mCPBA), perbenzoic acid (C6H5COOOH), peracetic acid (CH3COOOH), hydrogen peroxide (H2O2), and tert-butyl hydroperoxide (t-BuOOH).
The carbonyl center is activated by...
The carbonyl center is activated by...


