Two-dimensional (2D) polymers possess tremendous potential in diverse applications, including flexible electronics, coatings, and separation/filtration [1]. Due to their non-trivial topology, 2D polymers also pose many fundamental problems in statistical physics. Unlike their 1D counterparts adopting random coil configurations, 2D polymers maintain a flat sheet-like structure with minimal outof-plane crumpling. Despite recent advances in 2D polymer synthesis, establishing a robust model to study its physical properties still remains an open problem. In this talk, I will present recent experimental studies focusing on kinetoplast DNA (kDNA) at the single molecule level. A single kDNA is a 2D network of linked DNA rings that enables convenient manipulation of molecular topology to study the structure-property relationships [2,3]. I will discuss our recent experimental findings, unveiling the static and dynamic properties of kDNA in solution [4,5]. Meticulous observations of topology-dependent dynamics, universal scaling and its deviation from theoretical prediction provide profound insights into 2D polymer physics and highlight kDNA as a promising model system.

[1] A. D. Schlüter, P. Payamyar, and H. C. Öttinger, How the World Changes By Going from One- to Two-Dimensional Polymers in Solution, Macromol. Rapid Commun. 37, 1638 (2016).

[2] J. Chen, C. A. Rauch, J. H. White, P. T. Englund, and N. R. Cozzarelli, The Topology of the Kinetoplast DNA Network, Cell 80, 61 (1995).

[3] A. R. Klotz, B. W. Soh, and P. S. Doyle, Equilibrium Structure and Deformation Response of 2D Kinetoplast Sheets, Proc. Natl. Acad. Sci. U. S. A. 117, 121 (2020).

[4] I. Yadav, D. Al Sulaiman, B. W. Soh, and P. S. Doyle, Phase Transition of Catenated DNA Networks in Poly(Ethylene Glycol) Solutions, ACS Macro Lett. 10, 1429 (2021).

[5] I. Yadav, D. Al Sulaiman, and P. S. Doyle, Tuning the Topology of a Two-Dimensional Catenated DNA Network, Phys. Rev. Res. 5, 013141 (2023).