The significant amount of plastic litter in the form of microplastics (size <5 mm) is garnering attention owing to its potential threat to marine life. Reliable, cost- and time-efficient analysis methods for monitoring microplastic abundance globally are still missing. Several studies proposed a fast detection method by binding the solvatochromic dye Nile Red on the surface of microplastics and using fluorescence microscopy for their detection. All the staining approaches reported so far differ in terms of Nile Red concentration, solvents, and staining procedure. Here, we compare the staining protocols published prior to 2019 and propose an optimized staining protocol. Furthermore, we explore the potential of Nile Red staining in combination with photoluminescence spectroscopy to identify the polymer type and to distinguish plastics from non-plastics.

由于其对海洋生物的潜在威胁，大量以微塑料形式存在的塑料垃圾（尺寸<5毫米）受到关注。仍然缺乏可靠的，成本高效且省时的方法来监测全球塑料微粒的丰度。几项研究提出了一种快速检测方法，方法是将溶剂化变色染料尼罗红结合在微塑料表面上，并使用荧光显微镜对其进行检测。迄今为止，所有报道的染色方法在尼罗红浓度，溶剂和染色步骤方面均不同。在这里，我们比较了2019年之前发布的染色方案并提出了优化的染色方案。此外，