Conjugated/nonconjugated alternating copolymers for enhanced NIR-II fluorescence imaging and NIR-II photothermal-ferrotherapy

Abstract

Conjugated polymers hold great promise for NIR-II fluorescence imaging (FI)-guided NIR-II photothermal therapy (PTT) due to the advantages of easily modified chemical structures and adjustable NIR absorption. However, to achieve...

A selenium-based NIR-II photosensitizer for a highly effective and safe phototherapy plan

“…The development of BBTD-based D-A-D fluorophores operating within the NIR-II range has been widely studied, 46,55,56 but just a few of them exhibit a long emission wavelength beyond 1100 nm. [57][58][59][60] Another strategy to adjust the photophysical properties of fluorophores is by introducing heavy atoms into the fluorophore molecules. The heavy-atom effect is attributed to spin-orbit coupling and results in the T 1 → S 0 radiative processes.…”

“…The heavy-atom effect is attributed to spin-orbit coupling and results in the T 1 → S 0 radiative processes. 36,61 The effect may induce emission enhancement, 58 emission wavelength changes, and even an increase in phototherapeutic efficiency. [62][63][64][65][66] As a heavy atom, the introduction of selenium (Se) would increase the singlet-triplet (S-T) conversion process and result in more non-radiative decay.…”

Activatable Janus Nanoparticles for Precise NIR‐II Bioimaging and Synergistic Cancer Therapy

“…[23] NIR-II imaging has a higher spatial resolution (≈10 μm), deeper penetration depth of biological tissue (>2 cm), less tissue scattering, and negligible tissue autofluorescence. [24][25][26][27] Compared with other NIR-II fluorescent nanoprobes (e.g., carbon nanotubes, quantum dots, rare earthdoped nanoparticles, and organic dyes), [28][29][30][31] Ag 2 S nanoparticles, benefiting from their high quantum yield, size-dependent emission property, and good biocompatibility, exhibit outstanding in vivo bioimaging for monitoring tumor growth, in situ tracking of transplanted stem cells and imaging-guided precision tumor manipulation. [32] The identification of tumor-positive lesions with in vivo fluorescent bioimaging is mainly dependent on signal-to-background ratio (SBR).…”

Conjugated Polymer Coupled with Nonconjugated Segments for NIR-II Fluorescence/NIR-II Photoacoustic Imaging-Guided NIR-II Photothermal Therapy

“…Moreover, for the low band gap NIR-II absorption conjugated polymers, the nonradiative decay is much stronger than radiative decay and consequently encounters problems with the low NIR-II fluorescence quantum yield. To address these issues, Wu and Tang groups synthesized aggregation-induced emission segments containing conjugated polymers that increase the NIR-II FL. ,− Our group has developed a series of weak electron donor-doped conjugated polymers that enabled NIR-II FL imaging-guided NIR-II PTT therapy. − However, these developed conjugated polymers have low solubility in organic solution and formed π–π stacking interactions between polymers in the aggregated state of water-soluble nanoparticles (NPs), significantly reducing the NIR-II FL imaging quality. Hence, a significant challenge remains to develop NIR-II absorption conjugated polymers with promising antiquenching capability for performing NIR-II FL and NIR-II PA imaging-guided NIR-II PTT of tumors.…”