Bacterial Cellulose Ionogels as Chemosensory Supports

Chip J. Smith, Durgesh V. Wagle, Hugh M. O'Neill, Barbara R. Evans, Sheila N. Baker, Gary A. Baker

Research output: Contribution to journalArticlepeer-review

38 Scopus citations

Abstract

To fully leverage the advantages of ionic liquids for many applications, it is necessary to immobilize or encapsulate the fluids within an inert, robust, quasi-solid-state format that does not disrupt their many desirable, inherent features. The formation of ionogels represents a promising approach; however, many earlier approaches suffer from solvent/matrix incompatibility, optical opacity, embrittlement, matrix-limited thermal stability, and/or inadequate ionic liquid loading. We offer a solution to these limitations by demonstrating a straightforward and effective strategy toward flexible and durable ionogels comprising bacterial cellulose supports hosting in excess of 99% ionic liquid by total weight. Termed bacterial cellulose ionogels (BCIGs), these gels are prepared using a facile solvent-exchange process equally amenable to water-miscible and water-immiscible ionic liquids. A suite of characterization tools were used to study the preliminary (thermo)physical and structural properties of BCIGs, including no-deuterium nuclear magnetic resonance, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and X-ray diffraction. Our analyses reveal that the weblike structure and high crystallinity of the host bacterial cellulose microfibrils are retained within the BCIG. Notably, not only can BCIGs be tailored in terms of shape, thickness, and choice of ionic liquid, they can also be designed to host virtually any desired active, functional species, including fluorescent probes, nanoparticles (e.g., quantum dots, carbon nanotubes), and gas-capture reagents. In this paper, we also present results for fluorescent designer BCIG chemosensor films responsive to ammonia or hydrogen sulfide vapors on the basis of incorporating selective fluorogenic probes within the ionogels. Additionally, a thermometric BCIG hosting the excimer-forming fluorophore 1,3-bis(1-pyrenyl)propane was devised which exhibited a ratiometric (two-color) fluorescence output that responded precisely to changes in local temperature. The ionogel approach introduced here is simple and has broad generality, offering intriguing potential in (bio)analytical sensing, catalysis, membrane separations, electrochemistry, energy storage devices, and flexible electronics and displays.

Original languageEnglish
Pages (from-to)38042-38051
Number of pages10
JournalACS Applied Materials and Interfaces
Volume9
Issue number43
DOIs
StatePublished - Nov 1 2017

Funding

This work was supported by the Research Corporation for Science Advancement (G.A.B.) and by University of Missouri Research Board funding (S.N.B.). C.J.S. was supported by an IGERT trainee fellowship administered by the National Science Foundation (Grant. No. DGE-1069091). We acknowledge the support of the Center for Structural Molecular Biology (Contract FWP ERKP291) and the Biofuels Scientific Focus Area (Contract FWP ERKP752) by the Genomic Science Program funded by the U.S. Department of Energy Office of Science through the Office of Biological and Environmental Research (OBER). Oak Ridge National Laboratory is managed by UT-Battelle, LLC, for the U.S. Department of Energy under Contract DE-AC05-00OR22725.

Keywords

  • bacterial cellulose
  • excimer
  • fluorogenic probe
  • hydrogen sulfide
  • ionic liquids
  • ionogel

Fingerprint

Dive into the research topics of 'Bacterial Cellulose Ionogels as Chemosensory Supports'. Together they form a unique fingerprint.

Cite this