School of Chemistry, Sun Yat-Sen University, Guangzhou 510006, P.R. China.
Anal Methods. 2022 Sep 22;14(36):3598-3604. doi: 10.1039/d2ay00689h.
A highly sensitive and selective RGB color analysis for the detection of formaldehyde (FA) was developed by using a DNA functionalized gold nanoparticle (AuNPs-DNA) probe. When complementary oligonucleotides (oligo 2 and oligo 3) and a silver ion (Ag) were added to the AuNPs-DNA solution, triplex DNA was formed, resulting in the aggregation of AuNPs, and accompanied by a solution color change from red to purple. With the addition of formaldehyde, it reacted with Ag, decreased the stability of triplex DNA between AuNPs-DNA, induced the dispersion of AuNPs, and the color of AuNPs recovered to red. Therefore, the formaldehyde concentration could be estimated with the RGB (red, green, blue) values of the AuNP solution by using a smartphone application (APP). The value of the system was proportional to the concentration of formaldehyde within the range of 0.23-4.50 mg L, with a detection limit of 0.14 mg L. The method has been successfully applied to detect the residues of formaldehyde in vegetable samples and has the potential of the on-site determination of formaldehyde.
一种基于 DNA 功能化金纳米粒子(AuNPs-DNA)探针的高灵敏度和选择性的 RGB 颜色分析方法被开发用于检测甲醛(FA)。当互补寡核苷酸(oligo 2 和 oligo 3)和银离子(Ag)加入到 AuNPs-DNA 溶液中时，形成了三链 DNA，导致 AuNPs 的聚集，并伴随着溶液颜色从红色变为紫色。随着甲醛的加入，它与 Ag 反应，降低了 AuNPs-DNA 之间三链 DNA 的稳定性，诱导 AuNPs 的分散，AuNPs 的颜色恢复为红色。因此，可以通过智能手机应用程序(APP)使用 AuNP 溶液的 RGB(红色、绿色、蓝色)值来估计甲醛的浓度。该系统的 值与甲醛浓度在 0.23-4.50mg/L 范围内呈正比，检测限为 0.14mg/L。该方法已成功应用于检测蔬菜样品中甲醛的残留量，具有现场测定甲醛的潜力。
