Nanosecond SRS fiber amplifier for label-free near-infrared photoacoustic microscopy of lipids

Photoacoustics

Markus R. Seeger¹  Seemantini K. Nadkarni¹  Brett E. Bouma¹  Gijs van Soest²  Hwidon Lee²  Norman Lippok² 

[1] Wellman Center for Photomedicine, Harvard Medical School and Massachusetts General Hospital, 40 Blossom Street, Boston, MA 02114, USA;Harvard Medical School, Boston, Massachusetts, MA 02115, USA;

关键词: Fiber amplifier;    Photoacoustic microscopy;    Stimulated Raman scattering;    Lipids;    Label-free imaging;    Near-Infrared;   

DOI  :  

来源: DOAJ

【 摘 要 】

Near-infrared photoacoustics receives increasing interest as an intravital modality to sense key biomolecules. One of the most central types of biomolecules of interest are lipids as they constitute essential bio-hallmarks of cardiovascular and metabolic diseases and their in-vivo detection holds insightful information about disease progression and treatment monitoring. However, the full potential of near-infrared photoacoustic for high-resolution and high-sensitivity biomedical studies of lipids has so far not been exploited due a lack of appropriate excitation sources delivering short-pulses at high-repetition-rate, high-pulse-energy, and wavelength around 1200 nm. Here, we demonstrate a custom-built SRS fiber amplifier that provides optical excitations at 1192.8 nm, repetition rates of 200 kHz, pulse durations below 2 ns, and pulse energies beyond 5 μJ. We capitalize on the performance of our excitation source and show near-infrared photoacoustics resolving intrinsic lipid contrast in biomedically relevant specimens ranging from single cells to lipid-rich tissue with subcellular resolution.

【 授权许可】

Unknown