title: The Mechanisms and Biomedical Applications of an NIR BODIPY-Based Switchable Fluorescent Probe.
abstract: Highly environment-sensitive fluorophores have been desired for many biomedical applications. Because of the noninvasive operation, high sensitivity, and high specificity to the microenvironment change, they can be used as excellent probes for fluorescence sensing/imaging, cell tracking/imaging, molecular imaging for cancer, and so on (i.e., polarity, viscosity, temperature, or pH measurement). In this work, investigations of the switching mechanism of a recently reported near-infrared environment-sensitive fluorophore, ADP(CA)₂, were conducted. Besides, multiple potential biomedical applications of this switchable fluorescent probe have been demonstrated, including wash-free live-cell fluorescence imaging, in vivo tissue fluorescence imaging, temperature sensing, and ultrasound-switchable fluorescence (USF) imaging. The fluorescence of the ADP(CA)₂ is extremely sensitive to the microenvironment, especially polarity and viscosity. Our investigations showed that the fluorescence of ADP(CA)₂ can be switched on by low polarity, high viscosity, or the presence of protein and surfactants. In wash-free live-cell imaging, the fluorescence of ADP(CA)₂ inside cells was found much brighter than the dye-containing medium and was retained for at least two days. In all of the fluorescence imaging applications conducted in this study, high target-to-noise (>5-fold) was achieved. In addition, a high temperature sensitivity (73-fold per Celsius degree) of ADP(CA)₂-based temperature probes was found in temperature sensing.
authors.affiliation: Ultrasound and Optical Imaging Laboratory, Department of Bioengineering, The University of Texas at Arlington, Arlington, TX 76019, USA. bingbing.cheng@mavs.uta.edu.|Joint Biomedical Engineering Program, The University of Texas at Arlington and The University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA. bingbing.cheng@mavs.uta.edu.
authors.forename: Bingbing
authors.initials: B
authors.lastname: Cheng
authors.affiliation: Department of Chemistry, University of North Texas, Denton, TX 76203, USA. venu235@yahoo.com.
authors.forename: Venugopal
authors.initials: V
authors.lastname: Bandi
authors.affiliation: Ultrasound and Optical Imaging Laboratory, Department of Bioengineering, The University of Texas at Arlington, Arlington, TX 76019, USA. shuai.yu@mavs.uta.edu.|Joint Biomedical Engineering Program, The University of Texas at Arlington and The University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA. shuai.yu@mavs.uta.edu.
authors.forename: Shuai
authors.initials: S
authors.lastname: Yu
authors.affiliation: Department of Chemistry, University of North Texas, Denton, TX 76203, USA. francis.dsouza@unt.edu.
authors.forename: Francis
authors.initials: F
authors.lastname: D'Souza
authors.affiliation: Joint Biomedical Engineering Program, The University of Texas at Arlington and The University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA. knguyen@uta.edu.|Department of Bioengineering, The University of Texas at Arlington, Arlington, TX 76019, USA. knguyen@uta.edu.
authors.forename: Kytai T
authors.initials: KT
authors.lastname: Nguyen
authors.affiliation: Joint Biomedical Engineering Program, The University of Texas at Arlington and The University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA. yihong@uta.edu.|Department of Bioengineering, The University of Texas at Arlington, Arlington, TX 76019, USA. yihong@uta.edu.
authors.forename: Yi
authors.initials: Y
authors.lastname: Hong
authors.affiliation: Joint Biomedical Engineering Program, The University of Texas at Arlington and The University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA. ltang@uta.edu.|Department of Bioengineering, The University of Texas at Arlington, Arlington, TX 76019, USA. ltang@uta.edu.
authors.forename: Liping
authors.initials: L
authors.lastname: Tang
authors.affiliation: Ultrasound and Optical Imaging Laboratory, Department of Bioengineering, The University of Texas at Arlington, Arlington, TX 76019, USA. baohong@uta.edu.|Joint Biomedical Engineering Program, The University of Texas at Arlington and The University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA. baohong@uta.edu.
authors.forename: Baohong
authors.initials: B
authors.lastname: Yuan
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D001896:Boron Compounds / Q000737:chemistry; D058948:Cell Tracking; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry; D006801:Humans; D046911:Macromolecular Substances; D057054:Molecular Imaging; D015394:Molecular Structure; D061848:Optical Imaging; D019047:Phantoms, Imaging; D013501:Surface-Active Agents; D014463:Ultrasonography; D014783:Viscosity
chemical_list: C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D001896:Boron Compounds; D005456:Fluorescent Dyes; D046911:Macromolecular Substances; D013501:Surface-Active Agents
keywords: USF imaging; aza-BODIPY; environment-sensitive fluorophore; in vivo fluorescence imaging; near-infrared; switchable fluorescent probe; temperature sensing; wash-free live-cell imaging