This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1002/cjce.23566. This article is protected by copyright. All rights reserved. Accepted Article Yaser Dahman ORCID iD: 0000-0002-9118-5455 Functionalized Bacterial Cellulose Nanowhiskers as Long-Lasting Drug Nanocarrier for Antibiotics and Anticancer Drugs Mohamed M. Khattab, Yaser Dahman * Department of Chemical Engineering, Ryerson University, Toronto, ON, Canada *Corresponding author: e-mail: ydahman@ryerson.ca; Tel: +1416-979-5000, ext. 4080 ABSTRACT A nano drug carrier based on sustainable and biocompatible nanocellulose was developed for use in prolonged drug releases. The grafting of β-cyclodextrin (βCD) on bacterial cellulose nanowhiskers (BCNC) using citric acid (CA) as a green linker was performed. This led to the formation of functionalized BCNC-grafted-βCD (BCNC-g-βCD). Broad- spectrum antibiotic Ciprofloxacin (CIP) and anticancer drugs Doxorubicin (DOX) and Paclitaxel (PTX) were used as model drugs. These model drugs were conjugated to BCNC-g-βCD to form the drug-nanocarrier systems (BCNC-g-βCD-drug). The change in the nanowhiskers’ surface chemistry, morphology, and crystallinity was characterized by FTIR, solid-state 13 C NMR, scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD). The functionalized nanowhiskers showed a significant increase in the drug payloads, which ranged from 495 ±4–810 ±7 μg/mg, along with a radical improvement in the drug release profiles. For all of the developed drug-conjugated nanocarriers, the initial burst releases were reduced effectively. The observed drug releases showed a sustained and controlled manner, with cumulative releases of 75–90 % over 5–5.5 days. Nevertheless, an improved drug release performance was observed in the acidic pH of 6.4 that mimicked extracellular tumor