Skip to main content
Log in

Strong acid-assisted preparation of green-emissive carbon dots for fluorometric imaging of pH variation in living cells

  • Original Paper
  • Published:
Microchimica Acta Aims and scope Submit manuscript

Abstract

New green-emissive carbon dots (G-CDs) are described here and shown to be viable fluorescent nanoprobes for the detection of changes in cellular pH values. By using m-phenylenediamine as the carbon source, G-CDs with an absolute quantum yield of 36% were solvothermally synthesized in the presence of strong H2SO4. The G-CDs have an average size of 2.3 nm and display strong fluorescence with excitation/emission peaks at 450/510 nm. The fluorescence intensity depends on the pH value in the range from 6.0 to 10.0, affording the capability for sensitive detection of intracellular pH variation. The nanosensor with excellent photostability exhibited good fluorescence reversibility in different pH solutions, and showed excellent stability against the influence of other biological species. The nanoprobe was successfully used in confocal fluorescence microscopy to determine pH values in SMMC-7721 cells.

Schematic presentation of green-emissive carbon dots (G-CDs) synthesized using m-phenylenediamine and sufuric acid through a solvothermal method for real-time fluorometric monitoring of intracellular pH values. Mechanism can be ascribed to PET process from the electron lone pair in amino group to the CDs.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Scheme 1
Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6

Similar content being viewed by others

References

  1. Kennedy RT, Huang L, Aspinwall CA (1996) Extracellular pH is required for rapid release of insulin from Zn−insulin precipitates in β-cell secretory vesicles during exocytosis. J Am Chem Soc 118:1795–1796

    Article  CAS  Google Scholar 

  2. Janecki AJ, Montrose MH, Zimniak P, Zweibaum A, Tse CM, Khurana S, Donowitz M (1998) Subcellular redistribution is involved in acute regulation of the brush border Na+/H+ exchanger isoform 3 in human colon adenocarcinoma cell line caco-2: protein kinase C-mediated inhibition of the exchanger. J Biol Chem 273:8790–8798

    Article  CAS  Google Scholar 

  3. Zhang X, Lin Y, Gillies RJ (2010) Tumor pH and its measurement. J Nucl Med 51:1167–1170

    Article  CAS  Google Scholar 

  4. Schindler M, Grabski S, Hoff E, Simon SM (1996) Defective pH regulation of acidic compartments in human breast cancer cells (MCF-7) is normalized in adriamycin-resistant cells (MCF-7adr). Biochemistry 35:2811–2817

    Article  CAS  Google Scholar 

  5. Izumi H, Torigoe T, Ishiguchi H, Uramoto H, Yoshida Y, Tanabe M, Ise T, Murakami T, Yoshida T, Nomoto M, Kohno K (2003) Cellular pH regulators: potentially promising molecular targets for cancer chemotherapy. Cancer Treat Rev 29:541–549

    Article  CAS  Google Scholar 

  6. Hou JT, Ren WX, Li K, Seo J, Sharma A, Yu XQ, Kim JS (2017) Fluorescent bioimaging of pH: from design to applications. Chem Soc Rev 46:2076–2090

    Article  CAS  Google Scholar 

  7. Horak E, Kassal P, Hranjec M, Steinberg IM (2018) Benzimidazole functionalised Schiff bases: novel pH sensitive fluorescence turn-on chromoionophores for ion-selective optodes. Sensor Actuat B: Chem 258:415–423

    Article  CAS  Google Scholar 

  8. Bao L, Ding L, Hui J, Ju H (2016) A light-up imaging protocol for neutral pH-enhanced fluorescence detection of lysosomal neuraminidase activity in living cells. Chem Commun 52:12897–12900

    Article  CAS  Google Scholar 

  9. Tantama M, Hung YP, Yellen G (2011) Imaging intracellular pH in live cells with a genetically encoded red fluorescent protein sensor. J Am Chem Soc 133:10034–10037

    Article  CAS  Google Scholar 

  10. Esposito A, Gralle M, Dani MAC, Lange D, Wouters FS (2008) pHlameleons: a family of FRET-based protein sensors for quantitative pH imaging. Biochemistry 47:13115–13126

    Article  CAS  Google Scholar 

  11. Mutuyimana FP, Liu J, Na M, Nsanzamahoro S, Rao Z, Chen HL, Chen XG (2018) Synthesis of orange-red emissive carbon dots for fluorometric enzymatic determination of glucose. Microchim Acta 185:518

    Article  Google Scholar 

  12. Mutuyimana FP, Liu J, Nsanzamahoro S, Na M, Chen HL, Chen XG (2019) Yellow-emissive carbon dots as a fluorescent probe for chromium (VI). Microchim Acta 186:163

    Article  Google Scholar 

  13. Sun YQ, Wang XJ, Wang C, Tong DY, Wu Q, Jiang KL, Jiang YN, Wang CX, Yang MH (2018) Red emitting and highly stable carbon dots with dual response to pH values and ferric ions. Microchim Acta 185:83

    Article  Google Scholar 

  14. Shangguan JF, He DG, He XX, Wang KM, Xu FZ, Liu JQ, Tang JL, Yang X, Huang J (2016) Label-free carbon-dots-based ratiometric fluorescence pH nanoprobes for intracellular pH sensing. Anal Chem 88:7837–7843

    Article  CAS  Google Scholar 

  15. Wang RX, Wang XF, Sun YM (2017) One-step synthesis of self-doped carbon dots with highly photoluminescence as multifunctional biosensors for detection of iron ions and pH. Sensor Actuat B: Chem 241:73–79

    Article  CAS  Google Scholar 

  16. Hou P, Yang T, Liu H, Li YF, Huang CZ (2017) An active structure preservation method for developing functional graphitic carbon dots as an effective antibacterial agent and a sensitive pH and Al3+ nanosensor. Nanoscale 9:17334–17341

    Article  CAS  Google Scholar 

  17. Park SY, Lee HU, Park ES, Lee SC, Lee JW, Jeong SW, Kim CH, Lee YC, Huh YS, Lee J (2014) Photoluminescent green carbon nanodots from food-waste-derived sources: large-scale synthesis, properties, and biomedical applications. ACS Appl Mater Interfaces 6:3365–3370

    Article  CAS  Google Scholar 

  18. Liu DY, Qu F, Zhao XN, You JM (2015) Generalized one-pot strategy enabling different surface functionalizations of carbon nanodots to produce dual emissions in alcohol–water binary systems. J Phys Chem C 119:17979–17987

    Article  CAS  Google Scholar 

  19. Dong YQ, Pang HC, Yang HB, Guo CX, Shao JW, Chi YW, Li CM, Yu T (2013) Carbon-based dots co-doped with nitrogen and sulfur for high quantum yield and excitation-independent emission. Angew Chem Int Edit 52:7800–7804

    Article  CAS  Google Scholar 

  20. Ding H, Yu SB, Wei JS, Xiong HM (2016) Full-color light-emitting carbon dots with a surface-state-controlled luminescence mechanism. ACS Nano 10:484–491

    Article  CAS  Google Scholar 

  21. Wang N, Zheng AQ, Liu X, Chen JJ, Yang T, Chen ML, Wang JH (2018) Deep eutectic solvent assisted preparation of nitrogen/chloride doped carbon dots for intracellular biological sensing and live cell imaging. ACS Appl Mater Interfaces 10:7901–7909

    Article  CAS  Google Scholar 

  22. Wang Y, Lu LL, Peng H, Xu J, Wang FY, Qi RJ, Xu ZA, Zhang W (2016) Multi-doped carbon dots with ratiometric pH sensing properties for monitoring enzyme catalytic reactions. Chem Commun 52:9247–9250

    Article  CAS  Google Scholar 

  23. Sun S, Zhang L, Jiang K, Wu A, Lin HW (2016) Towards high-efficient red emissive carbon dots: facile preparation, unique properties, and applications as multifunctional theranostic agents. Chem Mater 28:8659–8668

    Article  CAS  Google Scholar 

  24. Zhou J, Zhou H, Tang JB, Deng S, Yan F, Li WJ, Qu MH (2017) Carbon dots doped with heteroatoms for fluorescent bioimaging: a review. Microchim Acta 184:343–368

    Article  CAS  Google Scholar 

  25. Jiang K, Sun S, Zhang L, Lu Y, Wu AG, Cai CZ, Lin HW (2015) Red, green, and blue luminescence by carbon dots: full-color emission tuning and multicolor cellular imaging. Angew Chem Int Edit 54:5360–5363

    Article  CAS  Google Scholar 

  26. Lindberg BJ, Hamrin K, Johansson G, Gelius U, Fahlman A, Nordling C, Siegbahn K (1970) Molecular spectroscopy by means of ESCA II. Sulfur compounds. Correlation of electron binding energy with structure. Phys Scr 1:286

    Article  CAS  Google Scholar 

  27. Ge JC, Jia QY, Liu WM, Guo L, Liu QY, Lan MH, Zhang HY, Meng XM, Wang PF (2015) Red-emissive carbon dots for fluorescent, photoacoustic, and thermal theranostics in living mice. Adv Mater 27:4169–4177

    Article  CAS  Google Scholar 

  28. Wang Q, Zhang SR, Zhong YG, Yang XF, Li Z, Li H (2017) Preparation of yellow-green-emissive carbon dots and their application in constructing a fluorescent turn-on nanoprobe for imaging of selenol in living cells. Anal Chem 89:1734–1741

    Article  CAS  Google Scholar 

  29. Shi BF, Su YB, Zhang LL, Liu RJ, Huang MJ, Zhao SL (2016) Nitrogen-rich functional groups carbon nanoparticles based fluorescent pH sensor with broad-range responding for environmental and live cells applications. Biosens Bioelectron 82:233–239

    Article  CAS  Google Scholar 

  30. Hutt JT, Aron ZD (2014) Synthesis and application of ratiometric and “turn-on” fluorescent pH sensors: an advanced organic undergraduate laboratory. J Chem Educ 91:1990–1994

    Article  CAS  Google Scholar 

  31. Wang YY, Yang XF, Zhong YG, Gong XY, Li Z, Li H (2016) Development of a red fluorescent light-up probe for highly selective and sensitive detection of vicinal dithiol-containing proteins in living cells. Chem Sci 7:518–524

    Article  CAS  Google Scholar 

  32. Zhang W, El-Reash YGA, Ding LJ, Lin ZZ, Lian Y, Song B, Yuan JL, Wang XD (2018) A lysosome-targeting nanosensor for simultaneous fluorometric imaging of intracellular pH values and temperature. Microchim Acta 185:533

    Article  Google Scholar 

  33. Wang L, Chen Y (2018) Lanthanide doped carbon dots as a fluorescence chromaticity- based pH probe. Microchim Acta 185:489

    Article  Google Scholar 

  34. Terrones YT, Leskow FC, Bordoni AV, Acebedo SL, Spagnuolo CC, Wolosiuk A (2017) A silica supported tricarbocyanine based pH nanosensor with a large stokes shift and a near infrared fluorescence response: performance in vitro and in live cells. J Mater Chem B 5:4031–4034

    Article  Google Scholar 

  35. Näreoja T, Deguchi T, Christ S, Peltomaa R, Prabhakar N, Fazeli E, Perälä N, Rosenholm JM, Arppe R, Soukka T (2017) Ratiometric sensing and imaging of intracellular pH using polyethyleneimine-coated photon upconversion nanoprobes. Anal Chem 89:1501–1508

    Article  Google Scholar 

Download references

Acknowledgements

The authors acknowledge the financial support by the National Natural Science Foundation of China (No. 21807068, 21373132, 21502109), the Natural Science Foundation of Shaanxi Province (No. 2017JQ2017), and the Project of Shaanxi University of Technology (SLGKY14-08).

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Xiaohui Ji.

Ethics declarations

The author(s) declare that they have no competing interests.

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Electronic supplementary material

ESM 1

(DOCX 3554 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Wang, Q., Yang, H., Zhang, Q. et al. Strong acid-assisted preparation of green-emissive carbon dots for fluorometric imaging of pH variation in living cells. Microchim Acta 186, 468 (2019). https://doi.org/10.1007/s00604-019-3569-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s00604-019-3569-4

Keywords

Navigation