Repository logo
HARVEST

Browsing by Author "Wilson, Lee"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Bioinspired complex cellulose nanorod-architectures: A model for dual-responsive smart carriers
    (Elsevier, 2024-12-17) Heidari Nia, Marzieh ; Garzia, Livia; Jawhar, Wajih; Wilson, Lee; van de Ven, Theo
    The synergy between nanomaterials as solid supports and supramolecular concepts has resulted in nanomaterials with hierarchical structure and enhanced functionality. Herein, we developed and investigated innovative supramolecular functionalities arising from the synergy between organic moieties and the preexisting nanoscale soft material backbones. Based on these complex molecular nano-architectures, a new nanorod carbohydrate polymer carrier was designed with bifunctional hairy nanocellulose (BHNC) to reveal dual-responsive advanced drug delivery (ADD). This carrier scavenges K+-ions within cancer cells, while simultaneously releasing doxorubicin, combining ion homeostasis disruption with targeted drug delivery. The BC ADD system resulted from cross-linking dibenzo-18-crown-6-ether (DB18C6) with BHNC particles. To enhance cellular internalization and facilitate tracking of uptake, the cellulose nanorod carrier was labeled with biotin and fluorescein isothiocyanate, referred to as BCFB. The BHNC serves as the backbone, while the immobilized DB18C6 moieties can capture doxorubicin via complex formation. The BCFB complex molecular nanorod carriers exhibit distinct ADD profiles with pH and K+-responsiveness. They were evaluated as biocompatible carriers for ADD in MDA-MB-231 breast cancer cells, including quantification of nanoparticle uptake and flow cytometry with KHOS cells. These cellulose-based carriers possess unique structure and properties with potential utility as phase transfer catalysts and as adsorbents for diverse waterborne contaminants.
  • Thumbnail Image
    Item
    Hybrid Chitosan Biosorbents: Tunable Adsorption at Surface and Micropore Domains
    (Biomimetics, 2024-11) Udoetok, Inimfon; Mohamed, Mohamed H.; Wilson, Lee
    Herein, we report a study that provides new insight on the knowledge gaps that relate to the role of biopolymer structure and adsorption properties for chitosan adsorbents that are cross-linked with glutaraldehyde. The systematic modification of chitosan cross-linked with glutaraldehyde (CG) and its quaternized forms (QCG) was studied in relation to the reaction conditions: mole ratios of reactants and pH conditions. Complementary adsorbent characterization employed 13C NMR/FTIR spectroscopy, TGA and DSC, point-zero-charge (PZC), solvent swelling, and sorption studies using selected dye probes. The spectral and thermal techniques provide complementary evidence that affirm the key role of cross-linker content and quaternization on variation of the physicochemical properties of chitosan. The PZC results reveal a neutral surface charge for the modified materials between pH 6.0 to 6.3 ± 0.3, as compared with pH 8.7 ± 0.4 for pristine chitosan. Solvent swelling in water decreased with greater cross-linking, while the QCG materials had greater swelling over CG materials due to enhanced hydration. The adsorption results reveal variable dye uptake properties according to the cross-linker content. Similarly, surface versus micropore adsorption was demonstrated, according to the nature and ionization state of the dye for the modified adsorbents, where the CG and QCG materials had tunable sorption properties that exceeded that of unmodified chitosan. A key step in tuning the structure and surface chemical properties of cross-linked chitosan involves pH control during synthesis. The facile tunability of the physicochemical properties of the modified biopolymers reported herein means that they possess features of biomimetics that are relevant to advanced drug delivery, antimicrobial materials for wound healing, biosensors, and biosorbents for biomedical applications.