Single antibody detection in a DNA origami nanoantenna

Martina Pfeiffer; Kateryna Trofymchuk; Simona Ranallo; Francesco Ricci; Florian Steiner; Fiona Cole; Viktorija Glembockyte; Philip Tinnefeld

doi:10.1016/j.isci.2021.103072

Single antibody detection in a DNA origami nanoantenna

iScience. 2021 Sep 1;24(9):103072. doi: 10.1016/j.isci.2021.103072. eCollection 2021 Sep 24.

Authors

Martina Pfeiffer¹, Kateryna Trofymchuk¹, Simona Ranallo^{2

3}, Francesco Ricci², Florian Steiner¹, Fiona Cole¹, Viktorija Glembockyte¹, Philip Tinnefeld¹

Affiliations

¹ Department of Chemistry and Center for NanoScience, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 München, Germany.
² Department of Chemical Science and Technologies, University of Rome, Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome, Italy.
³ Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, CA 93106, USA.

Abstract

DNA nanotechnology offers new biosensing approaches by templating different sensor and transducer components. Here, we combine DNA origami nanoantennas with label-free antibody detection by incorporating a nanoswitch in the plasmonic hotspot of the nanoantenna. The nanoswitch contains two antigens that are displaced by antibody binding, thereby eliciting a fluorescent signal. Single-antibody detection is demonstrated with a DNA origami integrated anti-digoxigenin antibody nanoswitch. In combination with the nanoantenna, the signal generated by the antibody is additionally amplified. This allows the detection of single antibodies on a portable smartphone microscope. Overall, fluorescence-enhanced antibody detection in DNA origami nanoantennas shows that fluorescence-enhanced biosensing can be expanded beyond the scope of the nucleic acids realm.

Keywords: Biochemistry; Nanotechnology; Optics; Physical chemistry.