Acrylate-Substituted Thiadiazoloquinoxaline Yields Ultralow Band Gap (0.56 eV) Conjugated Polymers for Efficient Photoacoustic Imaging AITranslate

Basic Information:

DOI：https://doi.org/10.1021/acsapm.1c00464

Chinese Library Classification Number:

Citation Information:

Conjugated polymers have been proven to be full of promising application in photoacoustic (PA) imaging. Generally, the absorption spectra of PA contrast agents lying in the near-infrared (NIR) II window are requisite to eliminate the light absorption and scattering of tissue, skin, and blood. In this concise study, strong acceptor acrylate-substituted thiadiazoloquinoxaline (ATQ) was developed and used to copolymerize with different donors, yielding three NIR II polymers. Results show that (i) ATQ-based polymers can reach an ultralow optical band gap of 0.56 eV; (ii) the ATQ-based polymer nanoparticles have good biocompatibility and high PA signal intensity with a tissue penetration depth up to 10 mm; and (iii) under NIR II laser irradiation, the signal-to-noise ratio of mouse cerebrovascular during in vivo PA imaging enhanced by 10 times after injecting ATQ-based nanoparticles. This work reveals that acrylate-substituted ATQ-based polymers, which can be easily synthesized and functionalized, extend the absorption spectra to longer wavelengths, and decrease the radiative decay rate (kr), are a promising class of NIR polymers for developing efficient PA contrast agents.