Novel thermo and ion-responsive copolymers based on metallo-base pair directed host-guest complexation for highly selective recognition of Hg2+ in aqueous solution

Xing-Long Zhou; Chang-Hai Zhou; Jue-Ying Gong; Quan-Wei Yu; Yang He; Xiao-Jie Ju; Liang-Yin Chu

doi:10.1016/j.jhazmat.2022.130610

Novel thermo and ion-responsive copolymers based on metallo-base pair directed host-guest complexation for highly selective recognition of Hg²⁺ in aqueous solution

J Hazard Mater. 2023 Mar 5:445:130610. doi: 10.1016/j.jhazmat.2022.130610. Epub 2022 Dec 16.

Authors

Xing-Long Zhou¹, Chang-Hai Zhou², Jue-Ying Gong², Quan-Wei Yu¹, Yang He³, Xiao-Jie Ju⁴, Liang-Yin Chu²

Affiliations

¹ Department of Respiratory and Critical Care Medicine, Targeted Tracer Research and Development Laboratory, West China Hospital, Sichuan University, Chengdu 610041, China.
² School of Chemical Engineering, Sichuan University, Chengdu 610065, China.
³ Department of Respiratory and Critical Care Medicine, Targeted Tracer Research and Development Laboratory, West China Hospital, Sichuan University, Chengdu 610041, China; Precision Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610044, China. Electronic address: heyangqx@scu.edu.cn.
⁴ School of Chemical Engineering, Sichuan University, Chengdu 610065, China. Electronic address: juxiaojie@scu.edu.cn.

PMID: 37056001
DOI: 10.1016/j.jhazmat.2022.130610

Abstract

The development of materials with highly selective recognition towards Hg²⁺ is of great significance in environmental monitoring. Herein, a novel thermo-responsive copolymer with Hg²⁺ recognition property is prepared via thermally-initiated copolymerization of 5'-O-Acryloyl 5-methyl-uridine (APU) and N-isopropylacrylamide (NIPAM). The chemical structure and stimuli-sensitive properties of poly(N-isopropylacrylamide-co-5-methyl-uridine) (P(NIPAM-co-APU)) linear polymers and hydrogel are thoroughly investigated. At the supramolecular level, P(NIPAM-co-APU) linear polymers could respond to both temperature and Hg²⁺ stimuli with highly selective recognition towards Hg²⁺ over other 18 metal ion species (at least 5 fold difference) and common anions. Upon capturing Hg²⁺ by APU units as host metal receptors, the lower critical solution temperature (LCST) of P(NIPAM-co-APU, PNU-7 and PNU-11) linear polymers are significantly shifted more than 10 °C due to the formation of stable APU-Hg²⁺-APU directed host-guest complexes. Accordingly, at the macroscopic level, P(NIPAM-co-APU) hydrogel display selective and robust recognition of Hg²⁺ under optimum conditions, and its maximum Hg²⁺ uptake capacity was 33.1 mg g^-1. This work provides a new option for Hg²⁺ recognition with high selectivity, which could be facilely integrated with other smart systems to achieve satisfactory detection of environmental Hg²⁺.

Keywords: 5-methyluridine derivatives; Mercury ion recognition; Metal-mediate Base-pairs; Multi-stimuli responsive polymers; Non-imprinted hydrogel.