Biomolecule in vitro detection

The sensitive in vitro detection of biomolecules is essential in numerous contexts, notably for medical applications, either for efficient pathogen identification or biomarker monitoring. The possibility to achieve high sensitivity with simple devices is thus an important objective to enhance the characterization of environmental samples or the diagnosis efficiency and consequently the prophylaxis or the patient care. For this purpose, we are developing the use of lanthanide-based photoluminescent nanoparticles as ultra-sensitive biological in vitro reporters. These nano-objects, synthesized in the Condensed Matter Physics Lab (Ecole Polytechnique) have remarkable optical properties, including exceptionally high brightness and photostability. We notably design the protocols and the instrumentation for fast multiplexed nitrocellulose-based assay (or Lateral Flow Assays ). Based on this approach, we realize the quantitative detection of multiple pathogens at ultra-high sensitivities (picomolar) for fast tests (Figure).

Top: Doped YVO₄ nanoparticles (absortion and emission of an Eu³⁺ doped particle, TEM image of a YVO₄:Eu nanoparticle, and luminescence of Eu³⁺ and Dy³⁺ doped nanoparticles under UV excitation. Middle: Custom-made detection device based on a smartphone and a low intensity UV excitation and images of multiplex LFA strips for the titration of enterotoxins (SEG, SEH and SEI). Bottom: Calibaration curves of entertoxin detection (black dots) and blind concentration measurements (colored dots)

We are furthermore developing innovative technologies for the ultra-sensitive detection (i.e. in the femto- and attomolar range) of protein and nucleic acids (DNA and RNA) in biological samples, as an alternative to the current usual and/or most sensitive tests (ELISA, ECLIA, Simoa, (q)PCR ,...), by respectively using immunolabeling or hybridization strategies . Based on custom-made instrumentation, we are performing the detection of multiple targets in various environments (aqueous buffers, plasma, cell culture,...), which are the basis of future diagnostic tests.

Right: Schematics of the detection device based on UV excitation and time-resolved collection. Left: Detection of insulin in buffer compare to ELISA performances.

References

F. Mousseau, C. Féraudet Tarisse, S. Simon, A. Alexandrou, C. I. Bouzigues. Multi-titration: the new method for implementing ultra-sensitive and quantitative multiplexed in-field immunoassays despite cross-reactivity. Anal. Chem 95, 13509 (2023)

F. Mousseau, C. Féraudet Tarisse, S. Simon, T. Gacoin, A. Alexandrou, C. I. Bouzigues. Luminescent Lanthanide Nanoparticle-Based Imaging enables Sensitive, Quantitative and Multiplexed in vitro Lateral Flow Immunoassays Nanoscale 13, 14814 (2021)

R. Kuhner, C. Bouzigues, C. Cardone, R. Lestini, A. Alexandrou, R. Vieira Perrella, T. Gacoin. Procédé de détection ultra-sensible à l’aide de particules photoluminescentes. FR2308669 (2023)

P. Preira, M. Richly, C. Bouzigues, A. Alexandrou, T. Gacoin. Test à diffusion capillaire mettant en œuvre des nanoparticules inorganiques photoluminescentes. WO2020/016308A1

P. Preira, M. Richly, C. Bouzigues, A. Alexandrou, T. Gacoin. Procédé de détection ultra-sensible à l’aide de particules photoluminescences WO2019/025618A1

P. Preira, M. Richly, C. Bouzigues, A. Alexandrou, T. Gacoin, R. Mohammedi. Particules luminescentes à base de terres rares et leur utilisation à titre d’agent de diagnostic. WO2018/211109A1