Idehara Wakaba, Haga Yuya, Tsujino Hirofumi, Ikuno Yudai, Manabe Sota, Hokaku Mii, Asahara Haruyasu, Higashisaka Kazuma, Tsutsumi Yasuo
School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka, 565-0871, Japan.
School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka, 565-0871, Japan; Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka, 565-0871, Japan.
Environ Res. 2025 Mar 15;269:120934. doi: 10.1016/j.envres.2025.120934. Epub 2025 Jan 23.
Microplastics (MPs), defined as plastic particles smaller than 5 mm, have garnered considerable attention owing to their potential biological impact on human health. These particles exhibit a range of physicochemical properties, including size, shape, and surface oxidation. Nile Red is a prominent tool for detecting microplastics, enabling staining for dynamic analyses within biological systems. However, the efficacy of Nile Red staining for surface-oxidized MPs remains unclear. Therefore, we applied Nile Red dye to stain surface-oxidized polyethylene and polyvinyl chloride and observed that both materials were effectively stained, although the fluorescence intensity varied according to different hydrophobic dynamics. Imaging analysis revealed a correlation between the fluorescence intensity score and the degree of surface oxidation, as determined using the carbonyl index calculated from attenuated total reflection-Fourier transform infrared spectroscopy data. Collectively, these findings offer novel analytical approaches for investigating environmental MPs, enhancing our understanding of their behavior and impact.
微塑料（MPs）被定义为尺寸小于5毫米的塑料颗粒，因其对人类健康的潜在生物学影响而备受关注。这些颗粒具有一系列物理化学性质，包括尺寸、形状和表面氧化。尼罗红是检测微塑料的一种重要工具，可用于生物系统内的动态分析染色。然而，尼罗红对表面氧化微塑料的染色效果仍不清楚。因此，我们应用尼罗红染料对表面氧化的聚乙烯和聚氯乙烯进行染色，观察到两种材料均被有效染色，尽管荧光强度因不同的疏水动力学而有所变化。成像分析显示，荧光强度评分与表面氧化程度之间存在相关性，表面氧化程度是根据衰减全反射-傅里叶变换红外光谱数据计算出的羰基指数确定的。总的来说，这些发现为研究环境微塑料提供了新的分析方法，增进了我们对其行为和影响的理解。
