title: Digital Concentration Readout of DNA by Absolute Quantification of Optically Countable Gold Nanorods.
abstract: Isolation and amplification procedures are indispensable for traditional single-molecule detection methods applied in low-abundance biomolecule analysis. Here, we describe a method for ultrasensitive detection of DNA through encoding a single target molecule with a single-countable nanometer-sized substitute (gold nanorod, AuNR) and enrichment of the substitute AuNRs into a limited region followed by accurate microscopic enumeration. The enrichment and the bright distinct color allow the AuNRs to be efficiently counted from as few as 1-2 to tens of thousands in 3 μL of test solution, which demonstrates the ability of rapid digital concentration readout of the target DNA. On this basis, a detection limit of 6.5 aM was achieved for DNA associated with human papillomavirus (HPV). Notably, our method requires neither complicated isolation and amplification procedures nor extremely expensive instruments and consumables.
authors: Institute of Optical Imaging and Sensing, Shenzhen Key Laboratory for Minimal Invasive Medical Technologies, Graduate School at Shenzhen, Tsinghua University , Shenzhen 518055, People's Republic of China.|Department of Physics, Tsinghua University , Beijing 100084, People's Republic of China.
authors: Guohua
authors: G
authors: Li
authors: Institute of Optical Imaging and Sensing, Shenzhen Key Laboratory for Minimal Invasive Medical Technologies, Graduate School at Shenzhen, Tsinghua University , Shenzhen 518055, People's Republic of China.|Department of Physics, Tsinghua University , Beijing 100084, People's Republic of China.
authors: Liang
authors: L
authors: Zhu
authors: Institute of Optical Imaging and Sensing, Shenzhen Key Laboratory for Minimal Invasive Medical Technologies, Graduate School at Shenzhen, Tsinghua University , Shenzhen 518055, People's Republic of China.|Department of Physics, Tsinghua University , Beijing 100084, People's Republic of China.
authors: Zhenjie
authors: Z
authors: Wu
authors: Institute of Optical Imaging and Sensing, Shenzhen Key Laboratory for Minimal Invasive Medical Technologies, Graduate School at Shenzhen, Tsinghua University , Shenzhen 518055, People's Republic of China.|Department of Physics, Tsinghua University , Beijing 100084, People's Republic of China.
authors: Yonghong
authors: Y
authors: He
authors: Shenzhen Key Laboratory of Neurosurgery, The First Affiliated Hospital of Shenzhen University , Shenzhen, 518035, China.
authors: Hui
authors: H
authors: Tan
authors: Institute of Optical Imaging and Sensing, Shenzhen Key Laboratory for Minimal Invasive Medical Technologies, Graduate School at Shenzhen, Tsinghua University , Shenzhen 518055, People's Republic of China.|Department of Physics, Tsinghua University , Beijing 100084, People's Republic of China.
authors: Shuqing
authors: S
authors: Sun
mesh_terms: D004279:DNA, Viral / Q000032:analysis*; D006046:Gold / Q000737:chemistry*; D043942:Nanotubes / Q000737:chemistry*; D055620:Optical Phenomena; D027383:Papillomaviridae / Q000737:chemistry* / Q000235:genetics; D013499:Surface Properties
chemical_list: D004279:DNA, Viral; D006046:Gold