Photoluminescence properties of N-doped carbon dots prepared in different solvents and applications in pH sensing

Yang, Mei; Li, Baoyan; Zhong, Kailiang; Lu, Yun

doi:10.1007/s10853-017-1700-7

Cited by 55 publications

(39 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…9 plots the size distribution histogram of CDs-b, which varies from 6 to 18 nm with average diameter of 11.9 nm, lager than that for most CDs ever reported. [37][38][39][40] Unexpectedly, the size of CDs-b outside the dialysis bag is bigger than that of CDs-s inside the dialysis, which is different from what we commonly see. As we all know, dialysis bag is designed according to the molecular weight cut-off to separate the particles with different molecular mass.…”

Section: Optical Properties Of Green Emissive Cds-ocontrasting

confidence: 70%

The synthesis of green fluorescent carbon dots for warm white LEDs

Zheng

Wang

et al. 2018

RSC Adv.

View full text Add to dashboard Cite

show abstract

Section: Optical Properties Of Green Emissive Cds-ocontrasting

confidence: 70%

The synthesis of green fluorescent carbon dots for warm white LEDs

Zheng

Wang

et al. 2018

RSC Adv.

View full text Add to dashboard Cite

show abstract

“…As reported by Yang et al, the fluorescence of CDs enhanced along with pH value increasing from 1.48 to 7.56, then slowed down when the pH reaches the values more than 8 [52]. This may be due to the deprotonation of surface groups of CDs at high pH values, and might form a new surface state [52]. As shown in Figure 1a(ii), the fluorescence lifetime of the CDs solutions with different pH values (pH = 2.6-8.6) increased linearly with the increase of the pH in the range of 1.6-3.7 ns.…”

Section: Fluorescence Characteristics Of Cds In Different Ph Solutionssupporting

confidence: 62%

“…The fluorescence intensity gradually increased with the increasing pH values, while the fluorescence intensity decreased a little when the pH exceeded 8.0. As reported by Yang et al, the fluorescence of CDs enhanced along with pH value increasing from 1.48 to 7.56, then slowed down when the pH reaches the values more than 8 [52]. This may be due to the deprotonation of surface groups of CDs at high pH values, and might form a new surface state [52].…”

Section: Fluorescence Characteristics Of Cds In Different Ph Solutionsmentioning

confidence: 57%

Carbon Dots for Intracellular pH Sensing with Fluorescence Lifetime Imaging Microscopy

et al. 2020

View full text Add to dashboard Cite

The monitoring of intracellular pH is of great importance for understanding intracellular trafficking and functions. It has various limitations for biosensing based on the fluorescence intensity or spectra study. In this research, pH-sensitive carbon dots (CDs) were employed for intracellular pH sensing with fluorescence lifetime imaging microscopy (FLIM) for the first time. FLIM is a highly sensitive method that is used to detect a microenvironment and it can overcome the limitations of biosensing methods based on fluorescence intensity. The different groups on the CDs surfaces changing with pH environments led to different fluorescence lifetime values. The CDs aqueous solution had a gradual change from 1.6 ns to 3.7 ns in the fluorescence lifetime with a pH range of 2.6–8.6. Similar fluorescence lifetime changes were found in pH buffer-treated living cells. The detection of lysosomes, cytoplasm, and nuclei in living cells was achieved by measuring the fluorescence lifetime of CDs. In particular, a phasor FLIM analysis was used to improve the pH imaging. Moreover, the effects of the coenzymes, amino acids, and proteins on the fluorescence lifetime of CDs were examined in order to mimic the complex microenvironment inside the cells.

show abstract

“…Fluorescent carbon dots (CDs) are a unique class of spherical nano-meter sized objects contributing to the most recent advances in the fields of sensors, [1][2][3][4][5][6] biosensors, [7][8][9][10] bioimaging, [11][12][13][14] drug delivery, [15][16][17][18] light emitting devices, [19][20] and photocatalysis. [21][22] Apart of their high fluorescent quantum yields, their use in diverse applications is based on their facile fabrication and a broad set of cheap precursor materials, their water solubility, low toxicity and good biocompatibility, as well as their favorable energy and charge transfer properties.…”

Section: Introductionmentioning

confidence: 99%

Supramolecular-Enhanced Charge Transfer within Entangled Polyamide Chains as the Origin of the Universal Blue Fluorescence of Polymer Carbon Dots

et al. 2018

View full text Add to dashboard Cite

The emission of a bright blue fluorescence is a unique feature common to the vast variety of polymer carbon dots (CDs) prepared from carboxylic acid and amine precursors. However, the difficulty to assign a precise chemical structure to this class of CDs yet hampers the comprehension of their underlying luminescence principle. In this work, we show that highly blue fluorescent model types of CDs can be prepared from citric acid and ethylenediamine through low temperature synthesis routes. Facilitating controlled polycondensation processes, the CDs reveal sizes of 1-1.5 nm formed by a compact network of short polyamide chains of about 10 monomer units. Density functional theory calculations of these model CDs uncover the existence of a spatially separated highest occupied molecular orbital and a lowest unoccupied molecular orbital located at the amide and carboxylic groups, respectively. Photoinduced charge transfer between these groups thus constitutes the origin of the strong blue fluorescence emission. Hydrogen-bond-mediated supramolecular interactions between the polyamide chains enabling a rigid network structure further contribute to the enhancement of the radiative process. Moreover, the photoinduced charge transfer processes in the polyamide network structure easily explain the performance of CDs in applications as revealed in studies on metal ion sensing. These findings thus are of general importance to the further development of polymer CDs with tailored properties as well as for the design of technological applications.

show abstract

Photoluminescence properties of N-doped carbon dots prepared in different solvents and applications in pH sensing

Cited by 55 publications

References 42 publications

The synthesis of green fluorescent carbon dots for warm white LEDs

The synthesis of green fluorescent carbon dots for warm white LEDs

Carbon Dots for Intracellular pH Sensing with Fluorescence Lifetime Imaging Microscopy

Supramolecular-Enhanced Charge Transfer within Entangled Polyamide Chains as the Origin of the Universal Blue Fluorescence of Polymer Carbon Dots

Contact Info

Product

Resources

About