Unveiling the rational development of stimuli-responsive silk fibroin-based ionogel formulations
Author(s)
Type
Journal Article
Abstract
We present an approach for the rational development of stimuli-responsive ionogels which can be formulated for precise control of multiple unique ionogel features and fill niche pharmaceutical applications. Ionogels are captivating materials, exhibiting self-healing characteristics, tunable mechanical and structural properties, high thermal stability, and electroconductivity. However, the majority of ionogels developed require complex chemistry, exhibit high viscosity, poor biocompatibility, and low biodegradability. In our work, we overcome these limitations. We employ a facile production process and strategically integrate silk fibroin, the biocompatible ionic liquids (ILs) choline acetate ([Cho][OAc]), choline dihydrogen phosphate ([Cho][DHP]), and choline chloride ([Cho][Cl]), traditional pharmaceutical excipients, and the model antiepileptic drug phenobarbital. In the absence of ILs, we failed to observe gel formation; yet in the presence of ILs, thermoresponsive ionogels formed. Systems were assessed via visual tests, transmission electron microscopy, confocal reflection microscopy, dynamic light scattering, zeta potential and rheology measurements. We formed diverse ionogels of strengths ranging between 18 and 642 Pa. Under 25 °C storage, formulations containing polyvinylpyrrolidone (PVP) showed an ionogel formation period ranging over 14 days, increasing in the order of [Cho][DHP], [Cho][OAc], and [Cho][Cl]. Formulations lacking PVP showed an ionogel formation period ranging over 32 days, increasing in the order of [Cho][OAc], [Cho][DHP] and [Cho][Cl]. By heating from 25 to 60 °C, immediately following preparation, thermoresponsive ionogels formed below 41 °C in the absence of PVP. Based on our experimental results and density functional theory calculations, we attribute ionogel formation to macromolecular crowding and confinement effects, further enhanced upon PVP inclusion. Holistically, applying our rational development strategy enables the production of ionogels of tunable physicochemical and rheological properties, enhanced drug solubility, and structural and energetic stability. We believe our rational development approach will advance the design of biomaterials and smart platforms for diverse drug delivery applications.
Date Issued
2023-08-08
Date Acceptance
2023-07-01
Citation
Chemistry of Materials, 2023, 35 (15), pp.5798-5808
ISSN
0897-4756
Publisher
American Chemical Society
Start Page
5798
End Page
5808
Journal / Book Title
Chemistry of Materials
Volume
35
Issue
15
Copyright Statement
© 2023 The Authors. Published by American Chemical Society. This publication is licensed under
CC-BY 4.0 .
CC-BY 4.0 .
License URL
Identifier
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:001033060200001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=a2bf6146997ec60c407a63945d4e92bb
Subjects
Chemistry
Chemistry, Physical
CHLORIDE
CONDUCTIVITY
GEL
GELATION
IONIC LIQUIDS
LONOGELS
Materials Science
Materials Science, Multidisciplinary
PERFORMANCE
Physical Sciences
Science & Technology
STABILITY
Technology
THERMORESPONSIVE HYDROGELS
TRANSPARENT
Publication Status
Published
Date Publish Online
2023-07-20