Pressure-Responsive Polymer Chemosensors for Hydrostatic-Pressure-Signal Detection: Poly-l-Lysine-Pyrene Conjugates

Soshi Wakako; Yumiko Hori; Tomokazu Kinoshita; Takao Saiki; Xinyi Qi; Koki Hasegawa; Yoshitane Imai; Tadashi Mori; Keiichi Nakagawa; Gaku Fukuhara

doi:10.1021/acsmacrolett.3c00427

Pressure-Responsive Polymer Chemosensors for Hydrostatic-Pressure-Signal Detection: Poly-l-Lysine-Pyrene Conjugates

ACS Macro Lett. 2023 Oct 17;12(10):1389-1395. doi: 10.1021/acsmacrolett.3c00427. Epub 2023 Oct 2.

Authors

Soshi Wakako¹, Yumiko Hori¹, Tomokazu Kinoshita¹, Takao Saiki², Xinyi Qi³, Koki Hasegawa⁴, Yoshitane Imai⁵, Tadashi Mori⁶, Keiichi Nakagawa^{2

3}, Gaku Fukuhara¹

Affiliations

¹ Department of Chemistry, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan.
² Department of Precision Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
³ Department of Bioengineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
⁴ Graduate School of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan.
⁵ Department of Applied Chemistry, Faculty of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan.
⁶ Department of Applied Chemistry, Osaka University, 2-1 Yamada-oka, Suita 565-0871, Japan.

PMID: 37782005
DOI: 10.1021/acsmacrolett.3c00427

Abstract

Stimulus-responsive polymer materials are an attractive alternative to conventional supramolecular and polymer assemblies for applications in sensing, imaging, and drug-delivery systems. Herein, we synthesized a series of pyrene-labeled α- and ε-poly-l-lysine conjugates with varying degrees of substitution (DSs). Hydrostatic-pressure-UV/vis, fluorescence, and excitation spectroscopies and fluorescence lifetime measurements revealed ground-state conformers and excited-state ensembles emitting fluorescence with variable intensities. The polylysine-based chemosensors demonstrated diverse ratiometric responses to hydrostatic pressure through adjustments in polar solvents, DSs, and polymer backbones. Additionally, the fluorescence chemosensor exhibited a promising g_lum value of 3.2 × 10^-3, indicating potential applications in chiral fluorescent materials. This study offers valuable insights into the development of smart hydrostatic-pressure-responsive polymer materials.