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Practical implementation, characterization and applications of a multi-colour time-gated luminescence microscope.

ABSTRACT: Time-gated luminescence microscopy using long-lifetime molecular probes can effectively eliminate autofluorescence to enable high contrast imaging. Here we investigate a new strategy of time-gated imaging for simultaneous visualisation of multiple species of microorganisms stained with long-lived complexes under low-background conditions. This is realized by imaging two pathogenic organisms (Giardia lamblia stained with a red europium probe and Cryptosporidium parvum with a green terbium probe) at UV wavelengths (320-400?nm) through synchronization of a flash lamp with high repetition rate (1?kHz) to a robust time-gating detection unit. This approach provides four times enhancement in signal-to-background ratio over non-time-gated imaging, while the average signal intensity also increases six-fold compared with that under UV LED excitation. The high sensitivity is further confirmed by imaging the single europium-doped Y?O?S nanocrystals (150?nm). We report technical details regarding the time-gating detection unit and demonstrate its compatibility with commercial epi-fluorescence microscopes, providing a valuable and convenient addition to standard laboratory equipment.

SUBMITTER: Zhang L

PROVIDER: S-EPMC4194433 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Practical implementation, characterization and applications of a multi-colour time-gated luminescence microscope.

Zhang Lixin L Zheng Xianlin X Deng Wei W Lu Yiqing Y Lechevallier Severine S Ye Zhiqiang Z Goldys Ewa M EM Dawes Judith M JM Piper James A JA Yuan Jingli J Verelst Marc M Jin Dayong D

Scientific reports 20141013

Time-gated luminescence microscopy using long-lifetime molecular probes can effectively eliminate autofluorescence to enable high contrast imaging. Here we investigate a new strategy of time-gated imaging for simultaneous visualisation of multiple species of microorganisms stained with long-lived complexes under low-background conditions. This is realized by imaging two pathogenic organisms (Giardia lamblia stained with a red europium probe and Cryptosporidium parvum with a green terbium probe) ...[more]

PMID: 25307702

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Practical implementation, characterization and applications of a multi-colour time-gated luminescence microscope.

Publications

Practical implementation, characterization and applications of a multi-colour time-gated luminescence microscope.

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