Labeling efficiency and toxicity evaluation of CdSe/ZnS quantum dots on Escherichia coli

Jin Yun Zhao, Li Min Jia, Wu Qi Song, Wen Li Zhang, Ying Mei Fu, Ying Zhang, Wen Wu Cao, Ye Sun, Jin Hua Zheng, Feng Min Zhang

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

In comparison with conventional organic dyes, quantum dots (QDs) have unique optical and electronic properties, which provide QDs with a wide scope of prospective application in biology and biomedicine. However, the toxicity of QDs and the fluorescence intensity of labeled bacteria must precede their application in bacterial imaging and tracing in vivo. Here, we show that treatment with CaCl2 significantly improved bacterial labeling efficiency of CdSe/ZnS QDs with the CdSe core size of ∼3.1 nm (relative fluorescence unit (RFU) value and ratio of fluorescent E. coli) with rising CdSe/ZnS QDs concentration in a concentration-dependent manner. At 12.5 nmol/L CdSe/ZnS QDs concentration, labeled Escherichia coli (E. coli) DH5a appeared as short rod-shaped and luminescent with normal size, and the survival rate and ultrastructure did not change in comparison to the control. But the ratio of fluorescent bacteria and RFU were very low. However, the survival rate of transformed E. coli was significantly inhibited by high CdSe/ZnS QDs concentrations (≥25 nmol/L). Moreover, internalization of CdSe/ZnS QDs resulted in ultrastructure damage of transformed E. coli in a concentration-dependent manner (≥25 nmol/L). Therefore, CdSe/ZnS QDs may not suitable for tracing of bacteria in vivo. Moreover, our study also revealed that colony-forming capability assay and transmission electron microscopy could be used to comprehensively evaluate the toxicity of QDs on labeled bacteria. Our findings do provide a new direction toward the improvement and modification of QDs for use in imaging and tracing studies in vivo.

Original languageEnglish (US)
Article number2424
JournalJournal of Nanoparticle Research
Volume16
Issue number6
DOIs
StatePublished - Jun 2014

Fingerprint

Toxicity
Quantum Dots
Escherichia
toxicity
Labeling
Escherichia coli
Escherichia Coli
Semiconductor quantum dots
marking
quantum dots
evaluation
Evaluation
Bacteria
bacteria
tracing
Tracing
Fluorescence
Ultrastructure
fluorescence
Imaging

All Science Journal Classification (ASJC) codes

  • Bioengineering
  • Chemistry(all)
  • Atomic and Molecular Physics, and Optics
  • Modeling and Simulation
  • Materials Science(all)
  • Condensed Matter Physics

Cite this

Zhao, J. Y., Jia, L. M., Song, W. Q., Zhang, W. L., Fu, Y. M., Zhang, Y., ... Zhang, F. M. (2014). Labeling efficiency and toxicity evaluation of CdSe/ZnS quantum dots on Escherichia coli. Journal of Nanoparticle Research, 16(6), [2424]. https://doi.org/10.1007/s11051-014-2424-0
Zhao, Jin Yun ; Jia, Li Min ; Song, Wu Qi ; Zhang, Wen Li ; Fu, Ying Mei ; Zhang, Ying ; Cao, Wen Wu ; Sun, Ye ; Zheng, Jin Hua ; Zhang, Feng Min. / Labeling efficiency and toxicity evaluation of CdSe/ZnS quantum dots on Escherichia coli. In: Journal of Nanoparticle Research. 2014 ; Vol. 16, No. 6.
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abstract = "In comparison with conventional organic dyes, quantum dots (QDs) have unique optical and electronic properties, which provide QDs with a wide scope of prospective application in biology and biomedicine. However, the toxicity of QDs and the fluorescence intensity of labeled bacteria must precede their application in bacterial imaging and tracing in vivo. Here, we show that treatment with CaCl2 significantly improved bacterial labeling efficiency of CdSe/ZnS QDs with the CdSe core size of ∼3.1 nm (relative fluorescence unit (RFU) value and ratio of fluorescent E. coli) with rising CdSe/ZnS QDs concentration in a concentration-dependent manner. At 12.5 nmol/L CdSe/ZnS QDs concentration, labeled Escherichia coli (E. coli) DH5a appeared as short rod-shaped and luminescent with normal size, and the survival rate and ultrastructure did not change in comparison to the control. But the ratio of fluorescent bacteria and RFU were very low. However, the survival rate of transformed E. coli was significantly inhibited by high CdSe/ZnS QDs concentrations (≥25 nmol/L). Moreover, internalization of CdSe/ZnS QDs resulted in ultrastructure damage of transformed E. coli in a concentration-dependent manner (≥25 nmol/L). Therefore, CdSe/ZnS QDs may not suitable for tracing of bacteria in vivo. Moreover, our study also revealed that colony-forming capability assay and transmission electron microscopy could be used to comprehensively evaluate the toxicity of QDs on labeled bacteria. Our findings do provide a new direction toward the improvement and modification of QDs for use in imaging and tracing studies in vivo.",
author = "Zhao, {Jin Yun} and Jia, {Li Min} and Song, {Wu Qi} and Zhang, {Wen Li} and Fu, {Ying Mei} and Ying Zhang and Cao, {Wen Wu} and Ye Sun and Zheng, {Jin Hua} and Zhang, {Feng Min}",
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Zhao, JY, Jia, LM, Song, WQ, Zhang, WL, Fu, YM, Zhang, Y, Cao, WW, Sun, Y, Zheng, JH & Zhang, FM 2014, 'Labeling efficiency and toxicity evaluation of CdSe/ZnS quantum dots on Escherichia coli', Journal of Nanoparticle Research, vol. 16, no. 6, 2424. https://doi.org/10.1007/s11051-014-2424-0

Labeling efficiency and toxicity evaluation of CdSe/ZnS quantum dots on Escherichia coli. / Zhao, Jin Yun; Jia, Li Min; Song, Wu Qi; Zhang, Wen Li; Fu, Ying Mei; Zhang, Ying; Cao, Wen Wu; Sun, Ye; Zheng, Jin Hua; Zhang, Feng Min.

In: Journal of Nanoparticle Research, Vol. 16, No. 6, 2424, 06.2014.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Labeling efficiency and toxicity evaluation of CdSe/ZnS quantum dots on Escherichia coli

AU - Zhao, Jin Yun

AU - Jia, Li Min

AU - Song, Wu Qi

AU - Zhang, Wen Li

AU - Fu, Ying Mei

AU - Zhang, Ying

AU - Cao, Wen Wu

AU - Sun, Ye

AU - Zheng, Jin Hua

AU - Zhang, Feng Min

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N2 - In comparison with conventional organic dyes, quantum dots (QDs) have unique optical and electronic properties, which provide QDs with a wide scope of prospective application in biology and biomedicine. However, the toxicity of QDs and the fluorescence intensity of labeled bacteria must precede their application in bacterial imaging and tracing in vivo. Here, we show that treatment with CaCl2 significantly improved bacterial labeling efficiency of CdSe/ZnS QDs with the CdSe core size of ∼3.1 nm (relative fluorescence unit (RFU) value and ratio of fluorescent E. coli) with rising CdSe/ZnS QDs concentration in a concentration-dependent manner. At 12.5 nmol/L CdSe/ZnS QDs concentration, labeled Escherichia coli (E. coli) DH5a appeared as short rod-shaped and luminescent with normal size, and the survival rate and ultrastructure did not change in comparison to the control. But the ratio of fluorescent bacteria and RFU were very low. However, the survival rate of transformed E. coli was significantly inhibited by high CdSe/ZnS QDs concentrations (≥25 nmol/L). Moreover, internalization of CdSe/ZnS QDs resulted in ultrastructure damage of transformed E. coli in a concentration-dependent manner (≥25 nmol/L). Therefore, CdSe/ZnS QDs may not suitable for tracing of bacteria in vivo. Moreover, our study also revealed that colony-forming capability assay and transmission electron microscopy could be used to comprehensively evaluate the toxicity of QDs on labeled bacteria. Our findings do provide a new direction toward the improvement and modification of QDs for use in imaging and tracing studies in vivo.

AB - In comparison with conventional organic dyes, quantum dots (QDs) have unique optical and electronic properties, which provide QDs with a wide scope of prospective application in biology and biomedicine. However, the toxicity of QDs and the fluorescence intensity of labeled bacteria must precede their application in bacterial imaging and tracing in vivo. Here, we show that treatment with CaCl2 significantly improved bacterial labeling efficiency of CdSe/ZnS QDs with the CdSe core size of ∼3.1 nm (relative fluorescence unit (RFU) value and ratio of fluorescent E. coli) with rising CdSe/ZnS QDs concentration in a concentration-dependent manner. At 12.5 nmol/L CdSe/ZnS QDs concentration, labeled Escherichia coli (E. coli) DH5a appeared as short rod-shaped and luminescent with normal size, and the survival rate and ultrastructure did not change in comparison to the control. But the ratio of fluorescent bacteria and RFU were very low. However, the survival rate of transformed E. coli was significantly inhibited by high CdSe/ZnS QDs concentrations (≥25 nmol/L). Moreover, internalization of CdSe/ZnS QDs resulted in ultrastructure damage of transformed E. coli in a concentration-dependent manner (≥25 nmol/L). Therefore, CdSe/ZnS QDs may not suitable for tracing of bacteria in vivo. Moreover, our study also revealed that colony-forming capability assay and transmission electron microscopy could be used to comprehensively evaluate the toxicity of QDs on labeled bacteria. Our findings do provide a new direction toward the improvement and modification of QDs for use in imaging and tracing studies in vivo.

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