CONTEXT

Multicolor imaging of bio-objects by one-photon excited fluorescence usually requires their labeling by various external molecular fluorophores, fluorescent proteins or quantum dots. While the major drawback of quantum dots is their cytotoxicity, organic fluorophores are strongly affected by photobleaching. Moreover, any external fluorescent agents affect the intracellular environment. Thus, developement of a label-free optical approache could be a powerful cell imaging tool. We propose to use silicon-based nanostructured dielectric thin films as luminescent screens for label-free bio-imaging

TECHNICAL DESCRIPTION

The nano-structured silicon-based fluorescent 40-100 nm thin films can be deposited on almost any suitable solid-state substrate. Cells which have to be observed are grown on the films without additional labelling. Specific physico-chemical interactions between different cell compartments and the luminescent screens on which the cells are immobilized, switch on various luminescent mechanisms in the substrates, ensuring multicolour imaging of the studied cells. Thus, subcellular components and/or organelles (nucleus, mitochondria, endoplasmic reticulum, cytoplasm …) can be easily visualized. Intensity of the cell coloration is much stronger than monocolour (green) auto-fluorescence signal of the same cells deposited directly onto the usual glass substrates (cover slips) and observed under the same conditions (excitation intensity and acquisition time).

DEVELOPMENT STAGE

Manufacturing of the «fluo-screen/glass» substrates is perfectly mastered by INL researchers. Current production rate is about 1200 substrates (1,5 cm x 1,5 cm) per hour. This new imaging approach was tested and validated in-vitro with various healthy and cancerous (animal and human) cell cultures.

BENEFITS

Our luminescent screens:

• allow label-free multicolour cell imaging;
• are totally compatible with standard fluorescent microscopy;
• are biocompatible and are friendly to the environment;
• may be disposable;
• have low production cost.

INDUSTRIAL APPLICATIONS

Accessories for bio Imaging systems

For further information, please contact us (Ref 04585-01)