The problem of micro- and nanoplastic (short: plastics) pollution is an increasing global issue and therefore several detection methods for plastics, also investigating the chemical nature via spectroscopy and chromatography, have been developed over the years. A new approach for identification and characterization of plastics is fluorescence lifetime imaging microscopy (FLIM) – a microspectroscopic method to detect fluorescence lifetime (τ) of plastics. We tested whether FLIM can be employed for the identification and characterization of plastics. Six types of plastics (ABS, PA6, PET, PLA, PPE, PU), with and without prior heat treatment, were subjected to FLIM with excitation wavelengths of 470 nm and 440 nm. The results provided mean τ (intensity weighted) values of 3.850 (+- 0.033) ns for ABS, 8.143 (+- 0.060) ns for PPE, 3.519 (+-0.090) ns for PET of a bottle from Germany and 3.564 (+-0.126) ns for PET of a bottle from the USA. The combination of mean intensity weighted τ and mean amplitude weighted τ values allowed for the significant differentiation of 52 (94.55 %) of the 55 possible plastic comparisons. Moreover, FLIM showed the potential for the sub-micrometer range plastic characterization, phasor analysis and allows for visual 3D-sectioning of samples that could be important for identification and characterization of plastics in tissue and environmental samples.

微米和纳米塑料（简称：塑料）污染问题是一个日益严重的全球性问题，因此，多年来，已经开发了几种塑料检测方法，还通过光谱学和色谱法研究了化学性质。鉴定和表征塑料的新方法是荧光寿命成像显微镜（FLIM）–一种检测荧光寿命（τ）的塑料。我们测试了FLIM是否可以用于塑料的鉴定和表征。对六种类型的塑料（ABS，PA6，PET，PLA，PPE，PU）进行了预热处理和未进行预热处理，然后分别用激发波长分别为470 nm和440 nm的FLIM进行了处理。结果提供的平均τ（强度加权）值分别为ABS为3.850（+-0.033）ns，PPE为8.143（+-0.060）ns，德国PET瓶为3.519（+ -0.090）ns和3.564（+-美国瓶装PET的误差为0.126）ns。平均强度加权τ和平均幅度加权τ的组合值允许对55个可能的塑料比较中的52个（94.55％）进行显着区分。此外，FLIM显示了亚微米范围的塑料表征，相量分析的潜力，并允许对样品进行可视3D切片，这对于组织和环境样品中塑料的鉴定和表征很重要。