Nanosensors and Bioanalytical Systems (N&SB), Analytical Chemistry Department, Faculty of Sciences, Aragon Institute of Nanoscience, University of Zaragoza, 50009, Zaragoza, Spain.
Nanosensors and Bioanalytical Systems (N&SB), Analytical Chemistry Department, Faculty of Sciences, University of Zaragoza, 50009, Zaragoza, Spain.
Anal Bioanal Chem. 2020 Jul;412(18):4261-4271. doi: 10.1007/s00216-020-02677-7. Epub 2020 May 12.
Diamino-oxidase (DAO), horseradish peroxidase (HRP), and tetramethylbenzidine (TMB) have been immobilized into cellulose to obtain circular cellulose test supports (CCTSs) for the determination of cadaverine (Cad) and putrescine (Put). During the enzymatic reaction, TMB is oxidized and a blue spot is obtained. This color (RGB coordinates) is measured with a smartphone and a commercial application. The highest sensitivity is provided by the component R and a linear response is observed for low biogenic amine (BA) concentrations, but a second-order polynomial response better fits the experimental results for a wider concentration range. This has been successfully explained with a model developed to explain the RGB values obtained in this type of analytical system. Optimization studies enable CCTSs to be obtained for Put and Cad determination, which could be used (kept at 4 °C) for at least 45 days if a stabilizer (StabilCoat™ or StabilGuard™) is added during its synthesis. In these conditions, the R coordinate follows the model up to at least 4 × 10 M Put and/or Cad (both analytes give the same response). The method permits the Put and Cad determination from 5 × 10 M up to 4 × 10 M (RSD = 3%, n = 3). The CCTSs have been applied to Put + Cad determination in a tuna sample without any interference by other biogenic amines. The concentration found statistically agrees with that obtained using a HPLC-MS-validated method. Graphical abstract.
二胺氧化酶（DAO）、辣根过氧化物酶（HRP）和四甲基联苯胺（TMB）已被固定到纤维素中，以获得用于测定腐胺（Cad）和精胺（Put）的圆形纤维素测试支持物（CCTS）。在酶促反应中，TMB 被氧化，得到一个蓝色斑点。使用智能手机和商业应用程序测量这种颜色（RGB 坐标）。最高的灵敏度由 R 成分提供，并且对于低生物胺（BA）浓度观察到线性响应，但是对于更宽的浓度范围，二阶多项式响应更好地拟合实验结果。通过开发一个模型成功地解释了这一点，该模型用于解释这种类型的分析系统中获得的 RGB 值。优化研究使得可以获得用于测定 Put 和 Cad 的 CCTS，如果在其合成过程中添加稳定剂（StabilCoat™或 StabilGuard™），则可以至少保持 45 天（在 4°C 下）。在这些条件下，R 坐标至少遵循模型到 4×10 M Put 和/或 Cad（两种分析物给出相同的响应）。该方法允许从 5×10 M 到 4×10 M 测定 Put 和 Cad（RSD = 3％，n = 3）。CCTS 已应用于金枪鱼样品中未加其他生物胺干扰的 Put + Cad 测定。统计上发现的浓度与使用经 HPLC-MS 验证的方法获得的浓度一致。图表摘要。
