荧光寿命成像（FLIM）技术基于时间分辨检测模式，能够有效消除组织自体荧光干扰，提升成像质量。氟硼荧染料以其优异的光学特性在荧光寿命成像领域极具应用潜力，但其在生物环境中的聚集猝灭效应限制了它的实际应用。本研究利用空间位阻策略设计合成了荧光染料MP-BDP。通过在氟硼荧染料的meso位引入具有大空间位阻的三甲基苯，同时实现了MP-BDP荧光寿命（4.3 ns vs 2.8 ns）和发光效率（76.7% vs 41.1%）的提升。并且，通过量子化学计算和飞秒瞬态吸收光谱进一步阐明了分子构型对染料发光激发态行为的影响，证明了大空间位阻不仅能够有效抑制构型相关的振动弛豫，提升发光性能，还能够抑制聚集诱导的发光猝灭，使氟硼荧染料在双光子活体荧光寿命成像方面表现出优异的性能。

荧光寿命显微成像（FLIM）已经广泛应用于生命科学研究领域，具有高灵敏和高特异性的特点，在对组织微环境进行定量表征方面具有独特优势，但由于成像速度相对较慢，限制了FLIM的活体应用。近年来，随着光电子器件和人工智能等技术的发展，开启了FLIM活体成像新篇章。介绍通过优化硬件和算法两方面提升时域和频域FLIM技术的成像速度，以及其在生物医学基础研究和临床疾病诊断中的应用研究进展。最后，对活体FLIM成像的未来发展进行展望。

Fluorescence imaging in the second near-infrared window (NIR-II, 900–1880nm) with less scattering background in biological tissues has been combined with the confocal microscopic system for achieving deep in vivo imaging with high spatial resolution. However, the traditional NIR-II fluorescence confocal microscope with separate excitation focus and detection pinhole makes it possess low confocal efficiency, as well as difficultly to adjust. Two types of upgraded NIR-II fluorescence confocal microscopes, sharing the same pinhole by excitation and emission focus, leading to higher confocal efficiency, are built in this work. One type is fiber-pinhole-based confocal microscope applicable to CW laser excitation. It is constructed for fluorescence intensity imaging with large depth, high stabilization and low cost, which could replace multiphoton fluorescence microscopy in some applications (e.g., cerebrovascular and hepatocellular imaging). The other type is air-pinhole-based confocal microscope applicable to femtosecond (fs) laser excitation. It can be employed not only for NIR-II fluorescence intensity imaging, but also for multi-channel fluorescence lifetime imaging to recognize different structures with similar fluorescence spectrum. Moreover, it can be facilely combined with multiphoton fluorescence microscopy. A single fs pulsed laser is utilized to achieve up-conversion (visible multiphoton fluorescence) and down-conversion (NIR-II one-photon fluorescence) excitation simultaneously, extending imaging spectral channels, and thus facilitates multi-structure and multi-functional observation.

自2001年被发明以来，超导纳米线单光子探测器（SNSPD）迅速成长为近红外波段的明星光子探测器，其在近红外波段如1550 nm处系统探测效率超过95%，暗计数率低于1 cps（counts per second），时间抖动优于10 ps，探测速率高于1 GHz，并广泛应用在量子信息领域。近年来，研究人员开始将SNSPD引入到生物领域，以替代在近红外波段具有低信噪比、多后脉冲的半导体单光子探测器。本文将介绍SNSPD的探测原理和性能指标，并系统地阐述SNSPD在生物领域中的应用现状和发展前景。

Apoptosis is very important for the maintenance of cellular homeostasis and is closely related to the occurrence and treatment of many diseases. Mitochondria in cells play a crucial role in programmed cell death and redox processes. Nicotinamide adenine dinucleotide (NAD(P)H) is the primary producer of energy in mitochondria, changing NAD(P)H can directly reflect the physiological state of mitochondria. Therefore, NAD(P)H can be used to evaluate metabolic response. In this paper, we propose a noninvasive detection method that uses two-photon fluorescence lifetime imaging microscopy (TP-FLIM) to characterize apoptosis by observing the binding kinetics of cellular endogenous NAD(P)H. The result shows that the average fluorescence lifetime of NAD(P)H and the fluorescence lifetime of protein-bound NAD(P)H will be affected by the changing pH, serum content, and oxygen concentration in the cell culture environment, and by the treatment with reagents such as H2O2 and paclitaxel. Taxol (PTX). This noninvasive detection method realized the dynamic detection of cellular endogenous substances and the assessment of apoptosis.