Carbon Dots for Single-Molecule Imaging of the Nucleolus

Abstract

Carbon dots are newly discovered bright fluorescent biolabeling probes that nonspecifically bind to multiple cellular structures. Here we report yellow-orange emissive carbon dots that spontaneously localize inside the nucleolus of HeLa cells, specifically binding to the RNA. Single-particle measurements of carbon dots show fluorescence-intensity fluctuations with superior brightness and photostability. These optical properties were used for performing blinking-assisted localization microscopy that shows organization of the nucleolar RNA with improved resolution. Our study opens up the opportunity for single-molecule imaging and super-resolution microscopy applications using fluorescent carbon dots.

Carbon Nanodots: A Review—From the Current Understanding of the Fundamental Photophysics to the Full Control of the Optical Response

“…Many authors attribute this tunability to a certain degree of inhomogeneity which typically affects CD samples, caused by the difficulty of tightly controlling the structural characteristics of the product obtained through most synthesis routes. Accordingly, CDs which display an emission independent of the excitation wavelength are considered quite homogeneous [10,18,190].…”

Subgram-Scale Synthesis of Biomass Waste-Derived Fluorescent Carbon Dots in Subcritical Water for Bioimaging, Sensing, and Solid-State Patterning

“… 1 − 4 Fluorescent carbon dots (FCDs), also known as carbon quantum dots or carbon nanodots, are among the most attractive of fluorescent nanomaterials, offering low cytotoxicity, favorable biocompatibility, and high photostability. 5 − 8 Consequently, a variety of synthetic strategies for FCDs have been developed, which can be classified into top-down and bottom-up approaches. 9 − 11 The top-down approach involves the cleavage of carbonaceous materials via acidic oxidation, hydrothermal treatment, or electrochemical exfoliation of carbon materials, such as graphite, graphene, carbon nanotubes, and carbon black.…”

Fluorescent carbon dots as intracellular imaging probes

“…They usually have carbonaceous graphitic core of <10 nm with varying degrees of oxidation (Shi, Li, & Ma, ). These fluorescent carbon nanoparticles can be synthesized from various carbon precursors such as citric acid (He et al, ; Khan, Verma, Chethana, & Nandi, ; Lan et al, ; Liu, Tian, Tian, Wang, & Yang, ; Shangguan et al, ; Shi et al, ; Shu et al, ; Wu, Li, Ling, Huang, & Jia, ; Yang et al, ; Zhang et al, ), activated carbon powder (Chai et al, ), hyaluronic acid (Zhang et al, ), phenylene diamine derivative (Cheng et al, ; Hua, Bao, & Wu, ; Liu, Y., Duan, W., et al, 2017; Song, W., Duan, W., et al, 2017; Xia, Chen, Zou, Yu, & Wang, ), flour (Zhang et al, ), 2‐azidoimidazole (Tang, Lin, Li, & Hu, ), thiomalic acid (Safavi, Ahmadi, Mohammadpour, & Zhou, ), aminosalicylic acid (Song, Y., Zhu, C., et al, 2017), sodium alginate‐tryptophan (Zhu et al, ), neutral red‐triethyl amine (Jiao et al, ), capsicum (Chen et al, ), ethanol (Gao, Ding, Zhu, & Tian, ; Qu, Zhu, Shao, Shi, & Tian, ; Zhu, Qu, Shao, Kong, & Tian, ), (3‐aminopropyl) triethoxysilane (Zou et al, ), malic acid (Zhi et al, ), folic acid (Liu et al, ), and so on. Furthermore, various cost‐effective and simple procedures have been established for their preparation that include solvothermal treatment (Chen et al, ; Zhu et al, ), thermal degradation (Shi et al, ), high temperature reflux (Lan et al, ), microwave‐assisted synthesis (He et al, ; Tang et al, ), pyrolysis (Zhang et al, , ), and oxidative acid treatment (Safavi et al, ).…”