Tunable Loading of Oligonucleotides with Secondary Structure on Gold Nanoparticles through a pH-Driven Method

Details

• Alternative Title:
  Bioconjug Chem
• Personal Author:
  Dam, Duncan Hieu M. ; Lee, Hyojin ; Lee, Raymond C. ; Kim, Ki Hun ; Kelleher, Neil L. ; Odom, Teri W.
• Description:
  This paper describes how pH can be used to control covalent attachment of oligonucleotides with secondary structure on gold nanoparticles (AuNPs). The highest loading of thiolated nucleic acids occurred at low pH (pH = 1.7) due to reduced repulsion between the negatively charged oligonucleotides and the AuNP surface. The packing of oligonucleotides at low pH decreased (single-stranded ≫ duplex > quadruplex) as the spatial footprint of secondary structure increased. As the pH increased, a decrease in the number of DNA strands grafted to the AuNPs was observed. Notably, the loading density depended on the flexibility and spatial organization of the secondary structures at all pH conditions. At the lowest pH tested, circular dichroism analysis revealed that G-quadruplex aptamers underwent a structural change (from parallel to antiparallel or vice versa), although the biological activity of the aptamer-loaded AuNPs was still maintained. We anticipate that pH-tuning can result in quantitative loading of oligonucleotides on various types of AuNPs with different shapes and surface capping layers.
• Subjects:
  Aptamers, Nucleotide Article Base Sequence G-Quadruplexes Gold Hydrogen-Ion Concentration Metal Nanoparticles Oligonucleotides
• Source:
  Bioconjug Chem. 2015; 26(2):279-285.
• Pubmed ID:
  25564799
• Pubmed Central ID:
  PMC4418649
• Document Type:
  Journal Article
• Funding:
  DP1 EB016540/DP/NCCDPHP CDC HHS/United States ; DP1 EB016540/EB/NIBIB NIH HHS/United States ; U54 CA119341/CA/NCI NIH HHS/United States
• Volume:
  26
• Issue:
  2
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha256:9b22fdbcf21f6d32a820d2ff099d1c59daf6bb753f899b80fade50dd812467e5
• Download URL:
  https://stacks.cdc.gov/view/cdc/30832/cdc_30832_DS1.pdf
• File Type:
  [PDF - 439.98 KB ]