Department of Industrial Environmental Engineering, College of Industrial Environmental Engineering, Gachon University, 1342 Seongnam-daero, Sujeong-gu, Seongnam-si, Gyeonggi-do 13120, Korea.
Department of BioNano Technology, Gachon University, 1342 Seongnam-daero, Sujeong-gu, Seongnam-si, Gyeonggi-do 13120, Korea.
Lab Chip. 2021 Feb 23;21(4):700-709. doi: 10.1039/d1lc00019e.
The present study investigated ultraviolet-induced in situ gold nanoparticles (AuNPs) coupled with loop-mediated isothermal amplification (LAMP) for the point-of-care testing (POCT) of two major infectious pathogens, namely, Coronavirus (COVID-19) and Enterococcus faecium (E. faecium spp.). In the process, gold ions in a gold chloride (HAuCl4) solution were reduced using trisodium citrate (Na3Ct), a reducing agent, and upon UV illumination, red-colored AuNPs were produced in the presence of LAMP amplicons. The nitrogenous bases of the target deoxyribonucleic acid (DNA) acted as a physical support for capturing gold ions dissolved in the sample. The high affinity of gold with the nitrogenous bases enabled facile detection within 10 min, and the detection limit of COVID-19 plasmid DNA was as low as 42 fg μL-1. To ensure POCT, we designed a portable device that contained arrays of reagent chambers and detection chambers. In the portable device, colorimetric reagents such as HAuCl4 and Na3Ct were contained in the reagent chambers; these reagents were subsequently transferred to the detection chambers where LAMP amplicons were present and thus allowed convenient sample delivery and multiplex detection. Owing to the high sensitivity of the in situ AuNPs, simplicity of portable device fabrication, and rapid colorimetric detection, we strongly believe that the fabricated portable device could serve as a kit for rapid POCT for instantaneous detection of infectious diseases, and could be readily usable at the bedside.
本研究调查了紫外线诱导的原位金纳米粒子（AuNPs）与环介导等温扩增（LAMP）相结合，用于即时检测（POCT）两种主要传染病原体，即冠状病毒（COVID-19）和粪肠球菌（E. faecium spp.）。在此过程中，使用三钠柠檬酸（Na3Ct）作为还原剂将金氯（HAuCl4）溶液中的金离子还原，在 LAMP 扩增子存在的情况下，经紫外线照射会产生红色 AuNPs。靶脱氧核糖核酸（DNA）的含氮碱基作为捕获溶解在样品中的金离子的物理支撑。金与含氮碱基的高亲和力使得在 10 分钟内能够轻松检测，COVID-19 质粒 DNA 的检测限低至 42fg μL-1。为了确保 POCT，我们设计了一种包含试剂腔和检测腔阵列的便携式设备。在便携式设备中，HAuCl4 和 Na3Ct 等显色试剂包含在试剂腔中；随后将这些试剂转移到存在 LAMP 扩增子的检测腔中，从而可以方便地进行样品输送和多重检测。由于原位 AuNPs 的高灵敏度、便携式设备制造的简单性和快速比色检测，我们坚信所制造的便携式设备可以作为一种试剂盒，用于快速即时检测传染病，并可在床边随时使用。
