Nanomechanical DNA Origami pH Sensors

Sensors

Akinori Kuzuya¹  Ryosuke Watanabe¹  Yusei Yamanaka¹  Takuya Tamaki¹  Masafumi Kaino¹ 

[1] Department of Chemistry and Materials Engineering, Kansai University, 3-3-35 Yamate, Suita, Osaka 564-8680, Japan; E-Mails:

关键词: DNA Origami;    DNA Nanotechnology;    Proton Detection;    pH Sensors;    i-motif;    AFM;    nanomechanical devices;    Single-Molecule Sensors;   

DOI  :  10.3390/s141019329

来源: mdpi

【 摘 要 】

Single-molecule pH sensors have been developed by utilizing molecular imaging of pH-responsive shape transition of nanomechanical DNA origami devices with atomic force microscopy (AFM). Short DNA fragments that can form i-motifs were introduced to nanomechanical DNA origami devices with pliers-like shape (DNA Origami Pliers), which consist of two levers of 170-nm long and 20-nm wide connected at a Holliday-junction fulcrum. DNA Origami Pliers can be observed as in three distinct forms; cross, antiparallel and parallel forms, and cross form is the dominant species when no additional interaction is introduced to DNA Origami Pliers. Introduction of nine pairs of 12-mer sequence (5′-AACCCCAACCCC-3′), which dimerize into i-motif quadruplexes upon protonation of cytosine, drives transition of DNA Origami Pliers from open cross form into closed parallel form under acidic conditions. Such pH-dependent transition was clearly imaged on mica in molecular resolution by AFM, showing potential application of the system to single-molecular pH sensors.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.