IPMA - Portuguese Institute of Sea and Atmosphere, Rua Alfredo Magalhães Ramalho, 6, 1495-165 Algés, Portugal; CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, Avenida General Norton de Matos S/N, 4450-208 Matosinhos, Portugal.
Grupo Química Analítica Aplicada (QANAP), Instituto Universitario de Medio Ambiente (IUMA), Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Spain.
Mar Pollut Bull. 2022 Aug;181:113911. doi: 10.1016/j.marpolbul.2022.113911. Epub 2022 Jul 9.
Potassium hydroxide (KOH) digestion protocols are currently applied to separate microplastics from biological samples, allowing efficient digestion with minor degradation of polymers in a time- and cost-effective way. For biota samples with high-fat content, KOH reacts with triglycerides generating an overlying soap layer, making difficult the digestion and solubilization and subsequent microplastics extraction. Here we studied the addition of Tween-20 in different concentrations to evaluate the effect on the soap layer of post-digested samples. Addition of 10 % of Tween-20 presented higher flow rate during filtration, being set as optimal value. Incorporation of Tween-20 in the extraction procedure increased recovery rates of LDPE, PC and PET and appears to have a protective effect on PC and PET degradation. Tween-20 did not interfere in FTIR spectrum of polymers available in the marine environment. Being low-toxic, makes addition of Tween-20 a simple and economical way to optimize KOH digestion protocols for microplastics extraction.
氢氧化钾 (KOH) 消解方案目前被应用于从生物样本中分离微塑料，以高效、经济的方式在短时间内消解，同时最小化聚合物的降解。对于高脂肪含量的生物样品，KOH 与甘油三酯反应生成上层的皂层，使得消化和解离以及随后的微塑料提取变得困难。在这里，我们研究了添加不同浓度的吐温-20 以评估其对消化后样品的皂层的影响。添加 10%的吐温-20 在过滤时表现出更高的流速，被设定为最佳值。在提取过程中加入吐温-20 提高了 LDPE、PC 和 PET 的回收率，并且似乎对 PC 和 PET 的降解具有保护作用。吐温-20 没有干扰海洋环境中可用聚合物的傅里叶变换红外光谱。由于低毒性，添加吐温-20 是优化 KOH 消解方案以提取微塑料的简单经济方法。
