Polysorbate- And DNA-Mediated Synthesis and Strong, Stable, and Tunable Near-Infrared Photoluminescence of Plasmonic Long-Body Nanosnowmen

Jiyeon Kim, Jae Myoung Kim, Minji Ha, Jeong Wook Oh, Jwa Min Nam

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


Direct photoluminescence (PL) from metal nanoparticles (NPs) without chemical dyes is promising for sensing and imaging applications since this offers a highly tunable platform for controlling and enhancing the signals in various conditions and does not suffer from photobleaching or photoblinking. It is, however, difficult to synthesize metal NPs with a high quantum yield (QY), particularly in the near-infrared (NIR) region where deep penetration and reduced light scattering are advantageous for bioimaging. Herein, we designed and synthesized Au-Ag long-body nanosnowman structures (LNSs), facilitated by polysorbate 20 (Tween 20). The DNA-engineered conductive junction between the head and body parts results in a charge transfer plasmon (CTP) mode in the NIR region. The junction morphology can be controlled by the DNA sequence on the Au core, and polythymine and polyadenine induced thick and thin junctions, respectively. We found that the LNSs with a thicker conductive junction generates the stronger CTP peak and PL signal than the LNSs with a thinner junction. The Au-Ag LNSs showed much higher intensities in both PL and QY than widely studied Au nanorods with similar localized surface plasmon resonance wavelengths, and notably, the LNSs displayed high photostability and robust, sustainable PL signals under continuous laser exposure for >15 h. Moreover, the PL emission from Au-Ag LNSs could be imaged in a deeper scattering medium than fluorescent silica NPs. Finally, highly robust PL-based cell images can be obtained using Au-Ag LNSs without significant signal change while repetitively imaging cells. The results offer the insights in plasmonic NIR probe design, and show that chemical dye-free LNSs can be a very promising candidate with a high QY and a robust, reliable NIR PL signal for NIR sensing and imaging applications.

Original languageEnglish
Pages (from-to)19853-19863
Number of pages11
JournalACS Nano
Issue number12
StatePublished - Dec 28 2021
Externally publishedYes


  • charge transfer plasmon
  • metal nanoparticles
  • metal photoluminescence
  • plasmonic long-body nanosnowman
  • plasmonic nanostructures


Dive into the research topics of 'Polysorbate- And DNA-Mediated Synthesis and Strong, Stable, and Tunable Near-Infrared Photoluminescence of Plasmonic Long-Body Nanosnowmen'. Together they form a unique fingerprint.

Cite this