Red-green-blue fluorescent hollow carbon nanoparticles isolated from chromatographic fractions for cellular imaging

Abstract

An as-synthesised hollow carbon nanoparticle (HC-NP) sample has been proved to be a relatively complex mixture, and its complexity can be reduced significantly by high-performance liquid chromatography. An unprecedented reduction in such complexity can reveal fractions of HC-NP with unique luminescence properties. While the UV-vis absorption profile for the HC-NP mixture is featureless, the HC-NP fractions do possess unique absorption bands and specific emission wavelengths. The HC-NP fractions are fully anatomised by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry, displaying their fragmentation mass ion features. The shell thickness and crystal lattices of the selected HC-NP fractions are determined as 6.13, 8.31, 2.22, and 8.66 nm, and 0.37, 0.35, 0.33, and 0.32 nm by transmission electron microscopy, respectively. The fractionated HC-NP show profound differences in emission quantum yield, allowing for brighter HC-NP to be isolated from an apparent low quantum yield mixture. Finally, red, green and blue emissive HC-NP are isolated from the as-synthesised HC-NP sample. They show good photostability and have been demonstrated to be excellent probes for cellular imaging.

Comparative study for N and S doped carbon dots: Synthesis, characterization and applications for Fe3+ probe and cellular imaging

“…These encouraging results prompted us to evaluate the feasibility of N-CDs as a new fluorescent marker for living cell imaging [67][68][69]. For effective cellular imaging, it is required that the selected fluorescent marker possesses not only optical merits but also low cytotoxicity [67].…”

Characterization and Analytical Separation of Fluorescent Carbon Nanodots

“…Later, we adopted RP-HPLC coupled with fluorescence detection (340/440 nm) for the fractionation of C-dots prepared from citric acid and 1,2-ethylenediamine using 10 mM NH 4 Ac (pH 4.5) and MeOH as the mobile phase [91]. Our group further reported the separation of hollow C-dots by the above established RP-HPLC method using UV detection (300 nm) with a binary solvent mixture of MeOH and 10 mM NH 4 Ac buffer (pH 5.5) as the mobile phase [108]. The fractions collected were found to be multicolor emissive, displaying red, green, and blue fluorescence under UV irradiation (365 nm).…”

“…The molecular weight obtained with these matrices was the same and the molecular weights for C-dots and F-C-dots were 267 / and 392 / , respectively. Soon afterward, our group reported the utility of MALDI-TOF MS for the characterization of the surface-attached functionalities on Cdots by examining their fragmentation patterns [91,96,108]. One typical example is the structural elucidation of C-dots obtained by microwave-assisted pyrolysis of citric acid and 1,2-ethylenediamine [91] (Figure 9).…”

“…Currently, chromatographic methods available for the separation of Cdots are anion-exchange high performance liquid chromatography (AE-HPLC) [95,100,101,107], reversed-phase-(RP-) HPLC [91,96,108], and size exclusion chromatography (SEC) [97,109].…”

Successful entrapment of carbon dots within flexible free-standing transparent mesoporous organic-inorganic silica hybrid films for photonic applications

“…These properties have led to a series of potential applications as in light emitting diodes [2,3], solar cells [4,5], sensing [6], catalysis [7], integration in photovoltaic devices etc. [8] and more importantly to a possible breakthrough in biosensing, bioimaging [9][10][11][12][13] and medical diagnosis [14].…”