与可见光区（400~700 nm）和近红外一区（NIR-I，700~900 nm）荧光成像（FL）相比，近红外二区（NIR-II，1000~1700 nm）荧光成像具有更深的穿透深度、更高的信噪比。开发亮度高、吸收/发射波长长、生物相容性好的NIR-II荧光探针一直是NIR-II荧光成像领域的一个重要研究方向。有机NIR-II荧光探针以其优异的生物相容性和良好的药代动力学特性而备受关注。本文从红移吸收/发射波长、提高荧光量子产率/摩尔吸光系数、改善生物相容性等角度系统总结了近年来花菁类染料、D-A-D小分子、聚合物点等有机NIR-II荧光探针的研究进展，重点介绍了具有代表性的荧光探针在活体NIR-II荧光成像中的应用，最后讨论了有机NIR-II荧光探针迈向临床应用面临的潜在挑战。

The absorption, scattering, and autofluorescence of biological tissues in short-wave infrared region (SWIR, 900–1700 nm) are relatively low, so SWIR fluorescence usually has deeper penetration into living tissues, and can show a higher signal-to-noise ratio when used for imaging in vivo. However, there are few types of organic SWIR fluorescent materials currently. In this work, p-azaquinodimethane (p-AQM) with a quinoid structure is used as the acceptor unit, and carbazole or fluorene with sp3 hybridization are used as the donor units, two conjugated polymers were synthesized. The quinone structure is conducive to the redshift of absorption and fluorescence spectra, and the sp3 hybridization structure is conducive to weakening the aggregation quenching of polymer fluorescence. PF and PCz exhibited absorption peaks of 492 nm and 508 nm, respectively. The emission peaks of the two polymers are 920 nm and 950 nm, respectively, both in the short-wave near infrared region. The quantum yield (QY) of PF and PCz is 0.4% and 0.3%, respectively.

研究了基于供体-受体共轭聚合物双(2-氧代二氢吲哚-3-亚基)-苯并二呋喃-二酮和联噻吩(PBIBDF-BT)薄膜晶体管的氧传感特性。在不同的氧气浓度下, 器件展示了空穴和电子载流子的传感特性, 如源漏电流、迁移率和亚阈值摆幅随着氧从半导体层内吸附/解吸附的过程中被调节。实验结果表明: 随着真空度从0.7 Pa上升到0.08 Pa, 即氧气的体积分数从~5.3×10-6降到~6×10-7, 对于P型传输的迁移率、源漏电流(开态)和亚阈值摆幅分别改变了-52.7%、-51.3%和48%, 而对于N型传输分别改变了42.3%、59.5%和-39%。并且腔室中氧气的浓度从~8×10-7降到~6×10-7,变化了~2×10-7, 相应的P型和N型源漏电流分别变化了-45.9%和31.1%。基于PBIBDF-BT聚合物薄膜晶体管能够实现对氧气的双极性检测和低的氧检测线。