ECsens, Department of Analytical Chemistry, University of Granada, 18071, Granada, Spain.
Unit of Excellence in Chemistry Applied to Biomedicine and the Environment of the University of Granada, Granada, Spain.
Mikrochim Acta. 2023 Mar 27;190(4):160. doi: 10.1007/s00604-023-05723-0.
Two colorimetric nanostructured sensor phases (Color-NSPs) for the determination of low concentrations of acid vapors in the atmosphere of paper storage rooms have been designed and characterized. The acid vapor determination is based on the color change that occurs in polyaniline (PANI) in the presence of acids when it goes from its emeraldine base form (blue) to its emeraldine salt form (green). To synthesize the Color-NSPs, two methods have been used, a one-step method performed by grafting polyaniline onto a cellulose membrane (Cellu-PANI) and a two-step method in which in the first step, polyaniline is grafted onto the surface of polymeric nanoparticles (NPs-PANI), and in a second step, NPs-PANI are immobilized into the pores of a nylon membrane (Nylon-NPs PANI). The response of the sensors versus acid vapor was measured by color coordinates with a photographic camera. A linear response range from 1 ppmv to 7 ppmv was found for both sensors, and the detection limits were 0.95 ppmv (1.2 % RSD) and 0.40 ppmv (0.8 % RSD) for Cellu-PANI and Nylon-NPs PANI, respectively. In addition, both sensors showed complete reversibility and a short exposition time (5 min). The potential applicability of the Color-NSPs in the control of the exposure of paper heritage collections to outdoor- and indoor-generated gaseous pollutants was demonstrated by determining acid vapors in museums. The method was validated with an external reference method; the paired test was applied, and p-values greater than 5% were obtained, indicating an excellent correlation and showing that the Color-NSPs reported are simple, fast, and an economical alternative to control and protect cultural heritage materials in indoor environments.
两种用于测定纸张储存室大气中低浓度酸蒸气的比色纳米结构传感器相（Color-NSP）已被设计和表征。酸蒸气的测定基于在酸存在下聚邻苯二胺（PANI）从其 emeraldine 碱形式（蓝色）变为 emeraldine 盐形式（绿色）时发生的颜色变化。为了合成 Color-NSP，使用了两种方法，一种是通过将聚苯胺接枝到纤维素膜上的一步法（Cellu-PANI），另一种是在第一步中将聚苯胺接枝到聚合物纳米粒子（NPs-PANI）表面，然后在第二步中，将 NPs-PANI 固定到尼龙膜的孔中（Nylon-NPs-PANI）。传感器对酸蒸气的响应通过带照相摄像机的颜色坐标进行测量。两种传感器的响应范围均为 1 ppmv 至 7 ppmv，检测限分别为 0.95 ppmv（1.2%RSD）和 0.40 ppmv（0.8%RSD），对于 Cellu-PANI 和 Nylon-NPs-PANI。此外，两种传感器均表现出完全的可逆性和短的暴露时间（5 分钟）。通过在博物馆中测定酸蒸气，证明了 Color-NSP 在控制纸质遗产收藏暴露于室外和室内产生的气态污染物方面的潜在适用性。该方法通过外部参考方法进行了验证；应用了配对检验，得到的 p 值大于 5%，表明存在极好的相关性，表明所报道的 Color-NSP 简单、快速，是控制和保护室内环境中文化遗产材料的经济替代方法。
