A new thread-based platform for colorimetric detection of nitrite was developed based on a modified Griess assay. Cellulose thread was chemically modified with a p-aminobenzoyl group and impregnated with chromotropic acid as a coupling reagent. The functionalization of the thread was confirmed by Raman spectroscopy. The diazotization and coupling reaction occurred along the length of the thread to produce a colored band in the presence of nitrite. This allowed the measurement of the length of thread in relation to nitrite concentration. In this method, the optimum concentration of chromotropic acid for nitrite detection was 5 mM in 0.10 M sulfuric acid mixed with 0.2 M citric acid. With a sample volume of 15 μL, the obtained working range for nitrite detection was from 50 to 1000 μM, where the lowest nitrite concentration that could produce color on the platform was 25 μM. The proposed method was successfully used to detect nitrite in three different types of samples with acceptable recoveries (92.4–115.4 %) and Relative Standard Deviation (RSD) (4.3–10.4 %).

基于改进的Griess分析法开发了一种新的基于线程的亚硝酸比色检测平台。纤维素线用p化学修饰-氨基苯甲酰基，并以发色酸浸渍作为偶联剂。通过拉曼光谱法证实了线的功能化。在亚硝酸盐存在下，重氮化和偶合反应沿线的长度发生，从而产生彩色带。这样就可以测量相对于亚硝酸盐浓度的线长。在这种方法中，用于亚硝酸盐检测的变色酸的最佳浓度是在0.10 M硫酸和0.2 M柠檬酸混合的情况下为5 mM。样品体积为15μL，所获得的亚硝酸盐检测工作范围为50至1000μM，其中可在平台上产生颜色的最低亚硝酸盐浓度为25μM。所提出的方法已成功用于检测三种不同类型样品中的亚硝酸盐，其回收率均可接受（92.4–115。