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This content will become publicly available on May 26, 2024

Title: Bio‐Templated Chiral Zeolitic Imidazolate Framework for Enantioselective Chemoresistive Sensing
Abstract

Chiral metal–organic frameworks (MOFs) have gained rising attention as ordered nanoporous materials for enantiomer separations, chiral catalysis, and sensing. Among those, chiral MOFs are generally obtained through complex synthetic routes by using a limited choice of reactive chiral organic precursors as the primary linkers or auxiliary ligands. Here, we report a template‐controlled synthesis of chiral MOFs from achiral precursors grown on chiral nematic cellulose‐derived nanostructured bio‐templates. We demonstrate that chiral MOFs, specifically, zeolitic imidazolate framework (ZIF),unc‐[Zn(2‐MeIm)2, 2‐MeIm=2‐methylimidazole], can be grown from regular precursors within nanoporous organized chiral nematic nanocellulosesviadirected assembly on twisted bundles of cellulose nanocrystals. The template‐grown chiral ZIF possesses tetragonal crystal structure with chiral space group ofP41, which is different from traditional cubic crystal structure ofI‐43 mfor freely grown conventional ZIF‐8. The uniaxially compressed dimensions of the unit cell of templated ZIF and crystalline dimensions are signatures of this structure. We observe that the templated chiral ZIF can facilitate the enantiotropic sensing. It shows enantioselective recognition and chiral sensing abilities with a low limit of detection of 39 μM and the corresponding limit of chiral detection of 300 μM for representative chiral amino acid, D‐ and L‐ alanine.

 
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NSF-PAR ID:
10425366
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
62
Issue:
30
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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