Recent Advances of NIR-II Emissive Semiconducting Polymer Dots for In Vivo Tumor Fluorescence Imaging and Theranostics

Abstract

Accurate diagnosis and treatment of tumors, one of the top global health problems, has always been the research focus of scientists and doctors. Near-infrared (NIR) emissive semiconducting polymers dots (Pdots) have demonstrated bright prospects in field of in vivo tumor fluorescence imaging owing to some of their intrinsic advantages, including good water-dispersibility, facile surface-functionalization, easily tunable optical properties, and good biocompatibility. During recent years, much effort has been devoted to developing Pdots with emission bands located in the second near-infrared (NIR-II, 1000–1700 nm) region, which hold great advantages of higher spatial resolution, better signal-to-background ratios (SBR), and deeper tissue penetration for solid-tumor imaging in comparison with the visible region (400–680 nm) and the first near-infrared (NIR-I, 680–900 nm) window, by virtue of the reduced tissue autofluorescence, minimal photon scattering, and low photon absorption. In this review, we mainly summarize the latest advances of NIR-II emissive semiconducting Pdots for in vivo tumor fluorescence imaging, including molecular engineering to improve the fluorescence quantum yields and surface functionalization to elevate the tumor-targeting capability. We also present several NIR-II theranostic Pdots used for integrated tumor fluorescence diagnosis and photothermal/photodynamic therapy. Finally, we give our perspectives on future developments in this field.

Semiconducting polymer dots for multifunctional integrated nanomedicine carriers

“…However, improvements could be made in tap & labeling, surface chemistry, and resistance to photobleaching. The recent research trend has shifted towards a focus on exploring emerging optical materials with emission wavelengths in the near-infrared domain, extending beyond the visible light domain [ 6 , 7 ]. Reflecting the research history of other classic optical materials, emerging trends are likely to emphasize energy conversion, quantum yield, biomimetic material development, and medical application innovation [ 8 ].…”

BODIPY-based near-infrared semiconducting polymer dot for selective yellow laser-excited cell imaging

“…Semiconducting polymer dots (Pdots) are a class of small (usually < ∼30 nm) uorescent probes for in vitro and in vivo imaging, biosensors, optical theranostics, and other biomedical applications. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] Pdots provide ultrahigh brightness, 18,19 excellent photostability, 20,21 low cellular toxicity, 22 good water dispersibility, tunable photophysical properties, and easy bioconjugation. 23 Pdots are also capable of multi-color emission at the single-particle level, with tunable relative uorescence intensities, 24 a capability that is useful for developing spectrallybarcoded probes for multiplexed assays.…”