State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Dairy Research Institute, Bright Dairy & Food Co., Ltd., Shanghai 200436, China.
School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
Biosensors (Basel). 2020 Dec 18;10(12):211. doi: 10.3390/bios10120211.
In this work, a paper device consisted of a patterned paper chip, wicking pads, and a base was fabricated. On the paper chip, DNA-gold nanoparticles (DNA-AuNPs) were deposited and Hg ions could be adsorbed by the DNA-AuNPs. The formed DNA-AuNP/Hg nanozyme could catalyze the tetramethylbenzidine (TMB)-HO chromogenic reaction. Due to the wicking pads, a larger volume of Hg sample could be applied to the paper device for Hg detection and therefore the color response could be enhanced. The paper device achieved a cut-off value of 50 nM by the naked eye for Hg under optimized conditions. Moreover, quantitative measurements could be implemented by using a desktop scanner and extracting grayscale values. A linear range of 50-2000 nM Hg was obtained with a detection limit of 10 nM. In addition, the paper device could be applied in the detection of environmental water samples with high recoveries ranging from 85.7% to 105.6%. The paper-device-based colorimetric detection was low-cost, simple, and demonstrated high potential in real-sample applications.
在这项工作中，制作了一种由图案化纸芯片、吸水垫和基底组成的纸基器件。在纸芯片上沉积了 DNA-金纳米粒子（DNA-AuNPs），Hg 离子可以被 DNA-AuNPs 吸附。形成的 DNA-AuNP/Hg 纳米酶可以催化四甲基联苯胺（TMB）-HO 显色反应。由于吸水垫的存在，可以将更大体积的 Hg 样品应用于纸基器件进行 Hg 检测，从而增强颜色响应。在优化条件下，该纸基器件通过肉眼可达到 50 nM 的截止值用于 Hg 的检测。此外，还可以通过使用台式扫描仪提取灰度值来进行定量测量。获得了 50-2000 nM Hg 的线性范围，检测限为 10 nM。此外，该纸基器件可用于检测环境水样，回收率范围为 85.7%至 105.6%。基于纸基的比色检测具有成本低、操作简单的特点，并在实际样品应用中表现出很大的潜力。
