Optimizing chemistry at the surface of prodrug-loaded cellulose nanofibrils with MAS-DNP

Akshay Kumar (1) , Bastien Watbled (2) , Isabelle Baussanne (2) , Sabine Hediger (1, 3) , Martine Demeunynck (3) , Gaël de Paëpe (1)

1 RM - Magnetic Resonance
2 DPM - Département de pharmacochimie moléculaire
3 CNRS - Centre National de la Recherche Scientifique

Studying the surface chemistry of functionalized cellulose nanofibrils at atomic scale is an ongoing challenge, mainly because FT-IR, NMR, XPS and RAMAN spectroscopy are limited in sensitivity or resolution. Herein, we show that dynamic nuclear polarization (DNP) enhanced 13 C and 15 N solid-state NMR is a uniquely suited technique to optimize the drug loading on nanocellulose using aqueous heterogenous chemistry. We compare the efficiency of two conventional coupling agents (DMTMM vs EDC/NHS) to bind a complex prodrug of ciprofloxacin designed for controlled drug release. Besides quantifying the drug grafting, we also evidence the challenge to control the concurrent prodrug adsorption and to optimize washing procedures. We notably highlight the presence of an unexpected prodrug cleavage mechanism triggered by carboxylates at the surface of the cellulose nanofibrils.

Domains: Chemical Sciences

Akshay Kumar, Bastien Watbled, Isabelle Baussanne, Sabine Hediger, Martine Demeunynck, et al.. Optimizing chemistry at the surface of prodrug-loaded cellulose nanofibrils with MAS-DNP. Communications Chemistry, 2023, 6 (1), pp.58. ⟨10.1038/s42004-023-00852-2⟩. ⟨hal-04049743⟩