Dual‐Mode Superresolution Imaging Using Charge Transfer Dynamics in Semiconducting Polymer Dots

Abstract

In a conjugated polymer‐based single‐particle heterojunction, stochastic fluctuations of the photogenerated hole population lead to spontaneous fluorescence switching. We found that 405 nm irradiation can induce charge recombination and activate the single‐particle emission. Based on these phenomena, we developed a novel class of semiconducting polymer dots that can operate in two superresolution imaging modes. The spontaneous switching mode offers efficient imaging of large areas, with <10 nm localization precision, while the photoactivation/deactivation mode offers slower imaging, with further improved localization precision (ca. 1 nm), showing advantages in resolving small structures that require high spatial resolution. Superresolution imaging of microtubules and clathrin‐coated pits was demonstrated, under both modes. The excellent localization precision and versatile imaging options provided by these nanoparticles offer clear advantages for imaging of various biological systems.

High‐Throughput Counting and Superresolution Mapping of Tetraspanins on Exosomes Using a Single‐Molecule Sensitive Flow Technique and Transistor‐like Semiconducting Polymer Dots

“…To achieve high-throughput superresolution mapping of biological structures,t he optical properties of the superresolution probe must be optimized according to the structure.D ue to the small size of exosomes and heterogeneity in exosome surface protein expression, it is difficult to resolve exosome surface structure efficiently using conventional superresolution probes,w hich possess insufficient imaging resolution or low switch-on frequency. [9,11] Here we designed anew class of photoswitching Pdots based on the principle of N-P-N transistors which offers adjustable switch-on frequency( duty cycle) and high localization…”

High‐Throughput Counting and Superresolution Mapping of Tetraspanins on Exosomes Using a Single‐Molecule Sensitive Flow Technique and Transistor‐like Semiconducting Polymer Dots

“…To achieve high-throughput superresolution mapping of biological structures,t he optical properties of the superresolution probe must be optimized according to the structure.D ue to the small size of exosomes and heterogeneity in exosome surface protein expression, it is difficult to resolve exosome surface structure efficiently using conventional superresolution probes,w hich possess insufficient imaging resolution or low switch-on frequency. [9,11] Here we designed anew class of photoswitching Pdots based on the principle of N-P-N transistors which offers adjustable switch-on frequency( duty cycle) and high localization precision. TheP dots were doped with metalloporphyrin derivatives and with phenyl-C61-butyric acid methyl ester (PCBM) to form as taggered ladder-type energy level alignment.…”

Nanoscale Metal-Organic Frameworks as Fluorescence Sensors for Food Safety

“…Fluorescence-based analysis emerged as a promising method to improve safety sensing [3][4][5][6]. Quantum dots, organic fluorescence dyes, and metallic nanoclusters are classical fluorescent materials; however, these materials inevitably showed weakness such as toxicity, poor selectivity and stability, and high costs [7][8][9]. Sensitive, selective, and cheap fluorescence materials are urgently required to design fluorescence sensors.…”