Fluorescence-informed photoacoustic discrimination of multiple chromophores by lifetime mapping optically gated responses

• Type of Material: Article
• Authors: Md S. Islam, Georgia Institute of Technology; Donald VanderLaan, Georgia Institute of Technology; Josie Hickman, Georgia Institute of Technology; Stanislav Emelianov, Emory University; Robert M. Dickson, Georgia Institute of Technology
• Language: English
• Date: 2023-08-01
• Publisher: Elsevier
• Publication Version: Final Published Version
• Copyright Statement: © 2023 The Authors
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): https://doi.org/10.1016%2Fj.pacs.2023.100529
• Title of Journal or Parent Work: Photoacoustics
• Volume: 32
• Start Page: 100529
• Grant/Funding Information: The authors gratefully acknowledge financial support from National Institutes of Health R01EB028916.
• Keywords: Imaging; Triplet-state; Photoacoustics; OADF; Fluorescence; Modulation; Lifetime
• Research Categories: Engineering, Biomedical; Chemistry, Biochemistry

Abstract

Synchronously Amplified Photoacoustic Image Recovery (SAPhIRe) offers improved background suppression using non-linear properties of modulatable contrast agents. Using SAPhIRe, multiple contrast agents in the same absorption window can be detected independently based on their unique triplet-state lifetimes. Here, we have demonstrated the unmixing of rose bengal and eosin Y signals from solution based on triplet-state lifetime mapping using both fluorescence and photoacoustics. Varying the pump-probe delay enables resolution and recovery of fast-decaying rose bengal and of slowly decaying eosin Y modulated photoacoustic signals, resulting from optically gated triplet state residence. Distinct images were reconstructed within tissue-mimicking phantom using the fitting coefficients of triplet-state lifetimes. Fluorescence was used to screen for modulation prior to photoacoustic imaging. The results suggest that lifetime unmixing can be utilized to simultaneously detect multiple pathologies with overlapping spectra using photoacoustic imaging.