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Title: The Impact of Water on Choline‐2‐Octenoic Ionic Liquid‐Facilitated Transdermal Transport

Ionic liquids (ILs) have been shown to be effective transdermal penetrants of pharmaceutically active ingredients, including small molecules and proteins. The presence of water within ionic liquids has been demonstrated to play a critical role in  their structural organization on the molecular level. However, the impact of water on IL transdermal transport efficacy has yet to be investigated. Herein, a water concentration gradient (0%–100% v/v) is tested to evaluate  choline trans‐2‐octenoic (CA2OE)‐mediated transport of a hydrophilic model drug dextran (10000 Da) in an ex vivo porcine skin model.Compared to 2:1, 1:1, 1:4, and 1:5 ionic ratio formulations, 50% v/v CA2OE 1:2‐water evidences the greatest success at transporting dextran to the acceptor fluid. Physicochemical characterization (dynamic light scattering (DLS), scanning electron microscopy (SEM), optical density (O.D.), Fourier transform infrared spectroscopy (FTIR), fluorescent microscopy, and rheology) is conducted to test both bulk and nanoscale‐level CA2OE 1:2–water interactions. It is hypothesized that the presence of microemulsions in the CA2OE 1:2 75% v/v formulation accounted for the severely decreased transport compared to the 50%. It is thus critical to comprehensively consider interactions between IL components, co‐solvents, anddrug molecules when formulating ILs for transdermal transport applications.

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Award ID(s):
2116597 1757220
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Therapeutics
Medium: X
Sponsoring Org:
National Science Foundation
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