When textile substrates biodegrade in landfills, the fate of textile colorants is unknown, and potentially poses an ecotoxic threat. In this study, we developed a systematic analytical method to evaluate the biodegradation of reactive dyes, the most common class of dye applied to cotton fabrics. The cotton fabrics were dyed with CI Reactive Blue 19 and biodegraded in soil in a laboratory‐controlled environment over intervals of 45 and 90 days. A dye isolation method using a low concentration of alkali (0.15% sodium hydroxide) was developed and applied (80°C for 1 hour) to isolate intact and degraded dye from the fabric samples. To quantify the intact dye isolated from the fabric samples, a quantification method was then developed using liquid chromatography‐photodiode array detection. The quantification method provided excellent linearity (R² = 0.9997 ± 0.0002), accuracy (% error = −2% ± 4), precision (% coefficient of variation = 2% ± 4) and sensitivity (lower limit of quantification = 0.4 ± 0.2 µg/mL) for concentrations ranging from 1 to 50 µg/mL. After validation, the method was applied and showed a reduction of dye in biodegraded samples (after 45 and 90 days) compared with undegraded control samples (0 days). To characterise the isolated dye degradation product, quadrupole time‐of‐flight tandem mass spectrometry was utilised. Analysis showed that the degradation product was formed by losing a group from the intact hydrolysed form of the dye, creating a more hydrophobic degradation product compared with the intact hydrolysed form of dye.

中文翻译：

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液相色谱-光电二极管阵列检测与高分辨率质谱联用对生物降解纤维素织物上CI活性蓝19的降解研究

当纺织品基质在垃圾填埋场中被生物降解时，纺织品着色剂的命运是未知的，并可能构成生态毒性威胁。在这项研究中，我们开发了一种系统的分析方法来评估活性染料的生物降解，活性染料是棉织物上最常见的染料。棉织物用CI Reactive Blue 19染色，并在实验室控制的环境中在45天和90天的间隔内在土壤中生物降解。开发了一种使用低浓度碱（0.15％氢氧化钠）的染料分离方法，并进行了应用（80°C 1小时），以从织物样品中分离出完整的和降解的染料。为了量化从织物样品中分离的完整染料，然后使用液相色谱-光电二极管阵列检测开发了一种量化方法。定量方法提供了出色的线性度（R ²  = 0.9997±0.0002），准确度（％误差= -2％±4），精密度（％变异系数= 2％±4）和灵敏度（定量下限= 0.4±0.2 µg / mL） 1至50 µg / mL。验证后，采用该方法，与未降解的对照样品（0天）相比，在生物降解的样品中（45天和90天后）染料减少。为了表征分离的染料降解产物，使用了四极杆飞行时间串联质谱。分析表明，降解产物是通过从染料的完整水解形式中失去一个基团而形成的，与染料的完整水解形式相比，生成的疏水性降解产物更多。