Optimizing the Synthesis of Red-Emissive Nitrogen-Doped Carbon Dots for Use in Bioimaging (original) (raw)

Carbon Dots as Nontoxic and High-Performance Fluorescence Imaging Agents

Fluorescent carbon dots (small carbon nanoparticles with the surface passivated by oligomeric PEG molecules) were evaluated for their cytotoxicity and in vivo toxicity and also for their optical imaging performance in reference to that of the commercially supplied CdSe/ZnS quantum dots. The results suggested that the carbon dots were biocompatible, and their performance as fluorescence imaging agents was competitive. The implication to the use of carbon dots for in vitro and in vivo applications is discussed.

Naturally Derived Carbon Dots as Bioimaging Agents

2021

The recent advances in nanoscience and technology have opened new avenues for carbon-based nanomaterials. Especially, Carbon dots (CDs) have gained significant attention due to their simple, economic and rapid green synthesis. These materials exhibit excellent water solubility, fluorescence emission, high fluorescence quantum yield, Ultraviolet (UV) to Infrared (IR) range absorbance and high bio-compatibility. Therefore, these materials are widely used for various biological applications including bio-imaging. With the integration and doping of surface passive agents and elements, respectively influenced the enhancement of fluorescence property of CDs. Also, the conjugation of receptor-based targeting ligands leads to targeted bioimaging. CDs in combination with other imaging contrast agents lead to the development of novel contrast agents for bimodal imaging and multimodal imaging techniques. The combination of diagnostic CDs with therapeutic agents resulted in the formation of the...

Carbon dots—Emerging light emitters for bioimaging, cancer therapy and optoelectronics

Nano Today, 2014

Carbon dots represent an emerging class of fluorescent materials and provide a broad application potential in various fields of biomedicine and optoelectronics. In this review, we introduce various synthetic strategies and basic photoluminescence properties of carbon dots, and then address their advanced in vitro and in vivo bioapplications including cell imaging, photoacoustic imaging, photodynamic therapy and targeted drug delivery. We further consider the applicability of carbon dots as components of light emitting diodes, which include carbon dot based electroluminescence, optical down-conversion, and hybrid plasmonic devices. The review concludes with an outlook towards future developments of these emerging light-emitting materials.

Recent advance of carbon dots in bio-related applications

Journal of Physics: Materials, 2020

Carbon dots (CDs) is a kind of carbon nanoparticles with a plentiful of surface functional groups and tunable emission with different excitation wavelength. Broadly speaking, CDs include carbon nanodots, carbon quantum dots, graphene quantum dots, carbonized polymer dots. Due to the unique nature, they are explored for various applications in the bio-related fields such as bioimaging, sensor for ion and (bio)molecules, catalyst, LED and other fields. They are viewed as great alternative tracers to the current fluorescent biomarkers in personalized nanomedicine and surgery operation monitoring. In this review, we summarized the recent progress in the development of CDs, including improvement in fluorescence properties, two-photon fluorescence, and integration with other modalities as theragnostic agents. Specifically, we discussed the preparation of dual-modal imaging agents to improve the accuracy of diagnosis, the combination of imaging and targeting functionality for the effective...

Advances in fluorescent carbon dots for biomedical applications

Advances in Physics: X

Carbon Dots are an emerging class of carbon-based nanoparticles, which since their discovery have attracted tremendous attention because of their exceptional fluorescent, chemical and mechanical properties as well as high photostability and biocompatibility. This unique combination of outstanding characteristics, together with the ease with which they can be synthesized, qualify carbon dots as highly promising materials for applications in electronics and biology, in particular, for biosensing, bioimaging, biotherapy and drug delivery. In this review, we present some of the most recent applications of carbon dots in biology and medicine, concentrating on their fluorescence properties, biocompatibility and efficiency; we also discuss how improvements could prompt their use in human studies. We illustrate how carbon dots, prepared through several facile and costeffective methods by either the bottom-up or the top-down route, can be used for imaging cells and bacteria and as sensing probes of metal cations. Moreover, we explain how their astonishing versatility has given rise to new biotherapy methods especially in the field of cancer theranostics.

Facile Synthesis of Nitrogen-doped Carbon Quantum Dots for Bio-imaging

MATEC Web of Conferences, 2016

Carbon quantum dots (CQD) with fascinating properties has gradually become a rising star as a new nanocarbon member due to its nonthreatening, abundant and inexpensive nature. This study reports on a facile preparation of fluorescent carbon quantum dots (CQD) from iota Carrageenan. CQD from iota Carrageenan was produced by hydrothermal method with a quantum yield (QY) of 16 to 20%. Doping the CQD with nitrogen by the addition of tetraethylene pentamine (TEPE) produced CQD with a QY of 77%. FTIR data confirmed the formation of hydroxyl, carboxylic and carbonyl functional groups as confirmed by the ToFSIMS data due to the presence of nitrogen bonds on the N-CQD produced with TEPE. The CQD and N-CQD produced are crystalline with graphitic structures because of the presence of sp2 graphitic d line spacing with the sizes ranging from 2 to 10nm. To examine the feasibility of using the CQD as nanoprobe in practical applications, labelling and detection of E.coli was performed. The E.coli fluoresced proving CQD as an effective probe in bio imaging application. This study has successfully demonstrated a facile approach of producing CQD with significant high quantum yields to fluorescent CQD for bio imaging applications. This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits distribution, and reproduction in any medium, provided the original work is properly cited.