Periodic Reporting for period 1 - PIRO (Phototransient InfraRed Holography (PIRO))
Période du rapport: 2023-05-01 au 2025-10-31
Molecules are the fundamental building blocks of all living matter. Disease is intrinsically linked to molecular malfunction: if undetected, tiny molecular errors can kill an organism. Visualising biology at the molecular level is thus key to advancing diagnostics and treatment. Yet, most current diagnostic imaging techniques only provide indirect molecular information that rarely allows drawing quantitatively meaningful conclusions. The PIRO project aims to overcome these limitations by developing a new vibrationally resolved holographic imaging methodology to enable high-resolution, quantitative, molecular imaging.
Compared to existing approaches, such as photothermal microscopy, a key aspect of PIRO is to shift from so-called “steady-state” heat-observations towards phototransient imaging. This paradigm shift conveniently eliminates heat-diffusion and time-dependent signal scaling effects thus ensuring high-quality, quantitative, vibrational imaging. Combined with phase-sensitive, holographic, widefield read-out the PIRO platform aims at providing truly quantitative, molecularly resolved, imaging at ~200 nm resolution across large fields of view at high throughput.
Technologically, PIRO’s ambitious goals are enabled by several core deliverables:
1. Advanced ultrafast infrared sources tailored for phototransient vibrational imaging.
2. A dedicated phototransient imaging system, the PIROscope, for rapid, high-resolution, label-free infrared imaging.
3. All-optical holographic lock-in schemes for widefield pump-probe imaging at the absolute sensitivity limit.
Enabled by these advances the PIRO project will then explore the fundamentally exciting transition from the transient to the well-studied steady state regime to both provide crucially necessary insight for informed imaging-system design and to uncover novel imaging methodologies based on dynamic observations. Finally, PIRO will take first steps towards enabling vibrationally-resolved phototransient diagnostics focusing on pressing challenges in the context of breast cancer diagnostics and antimicrobial resistance.
Compared to existing approaches, such as photothermal microscopy, a key aspect of PIRO is to shift from so-called “steady-state” heat-observations towards phototransient imaging. This paradigm shift conveniently eliminates heat-diffusion and time-dependent signal scaling effects thus ensuring high-quality, quantitative, vibrational imaging. Combined with phase-sensitive, holographic, widefield read-out the PIRO platform aims at providing truly quantitative, molecularly resolved, imaging at ~200 nm resolution across large fields of view at high throughput.
Technologically, PIRO’s ambitious goals are enabled by several core deliverables:
1. Advanced ultrafast infrared sources tailored for phototransient vibrational imaging.
2. A dedicated phototransient imaging system, the PIROscope, for rapid, high-resolution, label-free infrared imaging.
3. All-optical holographic lock-in schemes for widefield pump-probe imaging at the absolute sensitivity limit.
Enabled by these advances the PIRO project will then explore the fundamentally exciting transition from the transient to the well-studied steady state regime to both provide crucially necessary insight for informed imaging-system design and to uncover novel imaging methodologies based on dynamic observations. Finally, PIRO will take first steps towards enabling vibrationally-resolved phototransient diagnostics focusing on pressing challenges in the context of breast cancer diagnostics and antimicrobial resistance.
1. Fully implemented, optimised and validated an incubator housed PIROscope.
2. Established time-resolved PIROscopy with time delays ranging from femtoseconds to several tens of nanoseconds.
3. Implemented a freely-tunable femtosecond NIR source based on multistage amplification.
4. Devised and realised an integrated all-optical lock-in solution leveraging high-speed GPUdirect capabilities in combination with 100GigE cameras.
5. Performed time-dependent studies following vibrational overtone excitation to uncover transient-to-steady-state dynamics and photoacoustic phenomena.
6. Implemented the necessary assays and protocols to enable PIRO's work on antimicrobials.
7. Implemented a narrowband, freely tunable MIR source (5-10 mum) with a bandwidth of around 10 cm-1: sufficient to implement all PIRO-based imaging applications proposed.
8. Performed systematic measurements of MIR-excited systems (yeast, synthetic particles, chromosomes and bacteria) in air and aqueous environments with the core focus being validating the imaging aspects and implementing hyperspectral applications
2. Established time-resolved PIROscopy with time delays ranging from femtoseconds to several tens of nanoseconds.
3. Implemented a freely-tunable femtosecond NIR source based on multistage amplification.
4. Devised and realised an integrated all-optical lock-in solution leveraging high-speed GPUdirect capabilities in combination with 100GigE cameras.
5. Performed time-dependent studies following vibrational overtone excitation to uncover transient-to-steady-state dynamics and photoacoustic phenomena.
6. Implemented the necessary assays and protocols to enable PIRO's work on antimicrobials.
7. Implemented a narrowband, freely tunable MIR source (5-10 mum) with a bandwidth of around 10 cm-1: sufficient to implement all PIRO-based imaging applications proposed.
8. Performed systematic measurements of MIR-excited systems (yeast, synthetic particles, chromosomes and bacteria) in air and aqueous environments with the core focus being validating the imaging aspects and implementing hyperspectral applications
1. High-speed, GPU-direct enabled, real-time pump-probe hologram demodulation at 10 µrad/s e.g. <1 K temperature modulation using 100GigE technology.
2. Direct observation of coherent photoacoustic signals by photoexcitation of vibrational overtones followed by holography-enabled differential phase measurements.
3. Direct observation of coherent photoacoustic signals by photoexcitation of vibrational transitions followed by holography-enabled differential phase measurements (as 2. but with dramatically increase sensitivity).
4. Large field-of-view high speed MIR-excitation based phototransient imaging (> 200x200 mum); This is a major milestones as it underlines that the applications proposed in PIRO are achievable and realistic.
2. Direct observation of coherent photoacoustic signals by photoexcitation of vibrational overtones followed by holography-enabled differential phase measurements.
3. Direct observation of coherent photoacoustic signals by photoexcitation of vibrational transitions followed by holography-enabled differential phase measurements (as 2. but with dramatically increase sensitivity).
4. Large field-of-view high speed MIR-excitation based phototransient imaging (> 200x200 mum); This is a major milestones as it underlines that the applications proposed in PIRO are achievable and realistic.