One pot synthesis of highly luminescent polyethylene glycol anchored carbon dots functionalized with a nuclear localization signal peptide for cell nucleus imaging

Abstract

Strong blue fluorescent polyethylene glycol (PEG) anchored carbon nitride dots (CDs@PEG) with a high quantum yield (QY) of 75.8% have been synthesized by a one step hydrothermal treatment. CDs with a diameter of ca. 6 nm are well dispersed in water and present a graphite-like structure. Photoluminescence (PL) studies reveal that CDs display excitation-dependent behavior and are stable under various test conditions. Based on the as-prepared CDs, we designed novel cell nucleus targeting imaging carbon dots functionalized with a nuclear localization signal (NLS) peptide. The favourable biocompatibilities of CDs and NLS modified CDs (NLS-CDs) are confirmed by in vitro cytotoxicity assays. Importantly, intracellular localization experiments in MCF7 and A549 cells demonstrate that NLS-CDs could be internalized in the nucleus and show blue light, which indicates that CDs may serve as cell nucleus imaging probes.

A carbon dots based fluorescent probe for selective and sensitive detection of hemoglobin

“…A c c e p t e d M a n u s c r i p t 7 The existence of surface functional groups of CDs was studied using FT-IR spectrometry. As (Fig.…”

“…Compared with some conventional semiconductor quantum dots with heavy metal cores, CDs are superior in terms of low cytotoxicity, excellent aqueous solubility, good biocompatibility, broader photoluminescence profiles, and high photostability [4,5]. More attentions have been paid to CDs, including their synthesis and biochemical applications [6][7][8]. Recent studies based on the fluorescence variation of CDs in the detection process, CDs have been utilized to monitor many substances, such as Cu 2+ , Fe 3+ , methylmercury, and thrombin [9][10][11][12].…”

Carbon “Quantum” Dots for Fluorescence Labeling of Cells

“…33 While some accumulation within the cell nucleus was detected, majority of the carbon dots were found to be residing in the cytoplasm and cell membrane. 33 However, most of the reported studies might be considered as being exploratory in nature, and more experiments based on carbon dots of more desirable properties (very bright fluorescence emissions, compactness, etc.) are still needed, especially for broader applications to include stem cells and other special cell lines.…”

Bright-Yellow-Emissive N-Doped Carbon Dots: Preparation, Cellular Imaging, and Bifunctional Sensing

“…2,14 Due to difficulties in the removal of excess polymers, organic small molecules were applied to modify CDs later. [15][16][17][18][19] The relevant studies exhibit that types of functional groups have significant effects on fluorescence QYs of CDs but not emission maxima.…”