Magnetic Cellulose Nanocrystal Composites Functionalized with Benzalkonium Chloride for Potential Pathogen Control

Author(s)

• Kishore Chand (0000-0001-6199-7041), University of DaytonFollow
• Sydney Herzog, University of Dayton
• Mohammad Jahid Hasan, University of Texas at Austin
• Juganta Roy, West Texas A&M University
• Moses Ayitey-Adjin Jr., University of DaytonFollow
• Corbon M. Moss, Pennsylvania State University - Main CampusFollow
• Sarah Khan, University of Dayton
• Sara Tester, University of Dayton
• Monishita Deb, University of Cincinnati
• Katherine Schlaak, University of Cincinnati
• Sarah Watzman, University of Cincinnati
• Yvonne Sun, University of DaytonFollow
• Esteban Ureña-Benavides, University of Texas at San Antonio
• Erick S. Vasquez-Guardado, University of DaytonFollow

Document Type

Article

Publication Date

10-23-2026

Publication Source

Applied Nano Materials

Abstract

This study presents the design and synthesis of multifunctional magnetic cellulose nanocrystal (CNC) composites engineered for targeted adsorption and broad-spectrum antimicrobial applications. The nanocomposites were fabricated by anchoring mixed-valence Fe₃O₄ magnetic nanoparticles on eco-friendly CNC frameworks, followed by surface functionalization with benzalkonium chloride (BC), a potent quaternary ammonium biocide. Both sulfated (S) and TEMPO-oxidized CNC (T) variants were investigated across Fe₃O₄:CNC mass ratios of 1:2 and 1:4. Comprehensive structural, magnetic, and morphological characterization confirmed successful surface modification, superparamagnetic responsiveness, and uniform component dispersion. Thermogravimetric analysis confirmed precise compositional tailoring, capturing up to 87 wt.% inorganic magnetite core fractions, 11−34 wt.% organic CNC matrix, and up to 11 wt.% bound BC surfactant. Density functional theory (DFT) simulations complemented these insights by mapping favorable BC binding configurations and localized electronic-structure alterations. Equilibrium adsorption isotherms followed a dominant Langmuir monolayer pathway, with saturation capacities of 178−224 mg g⁻¹ and Langmuir correlation coefficients (R²) of 0.97−0.995. Quantum-chemical binding maps, together with robust within-variant interfacial charge inversions (e.g., from −22.1 to +8.5 mV for the 1:2 S formulation and from −20.4 to +11.2 mV for the 1:2 T formulation after BC addition), point to a cooperative physisorption−chemisorption transport mechanism. In vitro antibacterial assays showed pronounced, concentration-dependent inhibition zones of 7.9−12.8 mm against both Gram-positive (Listeria monocytogenes) and Gram-negative (Escherichia coli) foodborne pathogens, with bactericidal performance primarily correlating with BC loading and, to a lesser extent, with the underlying CNC surface chemistry. Together with the high adsorption capacity and magnetic recoverability of the CNC-Fe₃O₄ carrier, these results position BC@CNC-Fe₃O₄ nanocomposites as a promising platform for applications such as smart disinfection and active food-contact materials.

Inclusive pages

19774–19791

ISBN/ISSN

2574-0970

Document Version

Published Version

Comments

https://doi.org/10.1021/acsanm.6c03115

Copyright

© 2026 The Authors. This publication is licensed under a Creative Commons Attribution 4.0 International License.

Publisher

American Chemical Society

Volume

9

Peer Reviewed

yes

Issue

42

Keywords

magnetic cellulose nanocrystals, benzalkonium chloride, density functional theory, antibacterial activity, nanocomposites

eCommons Citation

Chand, Kishore; Herzog, Sydney; Hasan, Mohammad Jahid; Roy, Juganta; Ayitey-Adjin, Moses Jr.; Moss, Corbon M.; Khan, Sarah; Tester, Sara; Deb, Monishita; Schlaak, Katherine; Watzman, Sarah; Sun, Yvonne; Ureña-Benavides, Esteban; and Vasquez-Guardado, Erick S., "Magnetic Cellulose Nanocrystal Composites Functionalized with Benzalkonium Chloride for Potential Pathogen Control" (2026). Chemical and Materials Engineering Faculty Publications. 259.
https://ecommons.udayton.edu/cme_fac_pub/259