罗丹明B染色法快速测定土壤中微塑料

Determination of microplastics in soil by Rhodamine B rapid staining method

使用罗丹明B对微塑料进行快速染色,在波长为365 nm的紫外光下显示荧光,从而将微塑料在土壤介质中分离。选择聚乙烯、聚丙烯、聚氨酯和聚苯乙烯为试验材料,将乙醇和去离子水作为溶剂,对罗丹明B的着色能力进行研究;对处在不同条件下的微塑料荧光稳定性进行了评价。结果表明,乙醇是溶解罗丹明B的最佳溶剂,在红外光谱检测时罗丹明B染色对微塑料识别无显著影响,对处于不同条件下的微塑料仍保持荧光稳定。在加标回收实验中,ZnCl_(2)浮选液对土壤中微塑料分离效果较好,PE和PS回收率均达到99%以上,PP和PU的回收率均高于97%,同组试验回收率稳定,RSD值均小于2%。

Microplastics were quickly stained with Rhodamine B,which showed fluorescence under UV light at a wavelength of 365 nm,thus separating microplastics in the soil medium.PE,PP,PU and PS were selected as test materials,and ethanol and deionized water were used as solvents to study the coloring ability of Rhodamine B.The fluorescence stability of microplastics under different conditions was evaluated.The results showed that ethanol was the best solvent to dissolve Rhodamine B.Rhodamine B staining had no significant effect on the recognition of microplastics.The fluorescence of microplastics under different conditions is still stable.In the spiked recovery experiment,ZnCl_(2) flotation solution had a good separation effect on microplastics in soil.The recoveries of PE and PS were above 99%,and the recoveries of PP and PU were above 97%.The recoveries of the same group were stable,and the RSD values were all less than 2%.