TY - GEN
T1 - Upconversion Nanoformulation for Functional Imaging
AU - Chattopadhyay, Surojit
AU - Ghosh, Sandip
AU - Akhtar, Najim
AU - Yang, De Ming
AU - Chen, Chuan Lin
AU - Liu, Ren-Shyan
N1 - Publisher Copyright:
© 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.
PY - 2022
Y1 - 2022
N2 - Upconversion nanoparticles (UCNPs) are excited in the near infrared (NIR) biological transparency window, but emits anti-Stokes shifted photons in the visible that are extremely photostable and ideally suited for biomedical imaging. First, we synthesize a UCNP-mOrange fluorescent protein conjugate that forms a Forster resonance energy transfer (FRET) pair with UCNP as the donor and mOrange as the acceptor to report intracellular pH by fluorescence imaging. The inactivity of the mOrange protein in acidic pH will decrease FRET efficiency making the emission green dominated by the UCNPs. In basic pH, the emission will be relatively orange. This is the first demonstration of ratiometric and self-ratiometric demonstration of intracellular pH imaging by the UCNPs. Next, we show a smart multifunctional nanoformulation of the UCNPs (NaGdF4: Yb, Er- 99mTc) using radioisotope labelling that shows potential for multimodal imaging using fluorescence, CT, and SPECT modalities. Intricate chemistry to engineer the UCNPs resulted in stabilizing the nanoformulation in physiological and aqueous environments with reproducible signal acquisition. This work gathers the expertise of physicists, chemists, and biologists in an interdisciplinary platform.
AB - Upconversion nanoparticles (UCNPs) are excited in the near infrared (NIR) biological transparency window, but emits anti-Stokes shifted photons in the visible that are extremely photostable and ideally suited for biomedical imaging. First, we synthesize a UCNP-mOrange fluorescent protein conjugate that forms a Forster resonance energy transfer (FRET) pair with UCNP as the donor and mOrange as the acceptor to report intracellular pH by fluorescence imaging. The inactivity of the mOrange protein in acidic pH will decrease FRET efficiency making the emission green dominated by the UCNPs. In basic pH, the emission will be relatively orange. This is the first demonstration of ratiometric and self-ratiometric demonstration of intracellular pH imaging by the UCNPs. Next, we show a smart multifunctional nanoformulation of the UCNPs (NaGdF4: Yb, Er- 99mTc) using radioisotope labelling that shows potential for multimodal imaging using fluorescence, CT, and SPECT modalities. Intricate chemistry to engineer the UCNPs resulted in stabilizing the nanoformulation in physiological and aqueous environments with reproducible signal acquisition. This work gathers the expertise of physicists, chemists, and biologists in an interdisciplinary platform.
KW - Bioimaging
KW - Biosensing
KW - FRET
KW - Upconversion nanoparticles
KW - pH sensing
UR - http://www.scopus.com/inward/record.url?scp=85126234853&partnerID=8YFLogxK
U2 - 10.1007/978-3-030-92786-8_5
DO - 10.1007/978-3-030-92786-8_5
M3 - Conference contribution
AN - SCOPUS:85126234853
SN - 9783030927851
T3 - Springer Proceedings in Physics
SP - 35
EP - 42
BT - Future Trends and Challenges of Molecular Imaging and AI Innovation - Proceedings of FASMI 2020
A2 - Lin, Kang-Ping
A2 - Liu, Ren-Shyan
A2 - Yang, Bang-Hung
PB - Springer Science and Business Media Deutschland GmbH
T2 - International conference of Federation of Asian Societies for Molecular Imaging, FASMI 2020
Y2 - 20 November 2020 through 22 November 2020
ER -