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We have previously demonstrated that cellulose nanocrystals modified with poly(ethylenimine) (PEI-f-CNC) are capable of capturing volatile organic compounds (VOCs) associated with malodors. In this manuscript, we describe our efforts to develop a scalable synthesis of these materials from bulk cotton. This work culminated in a reliable protocol for the synthesis of unmodified cellulose nanocrystals (CNCs) from bulk cotton on a 0.5 kg scale. Additionally, we developed a protocol for the modification of the CNCs by means of sequential 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) oxidation and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) coupling to modify their surface with poly(ethylenimine) on a 100 g scale. Subsequently, we evaluated the performance of the PEI-f-CNC materials that were prepared in a series of VOC capture experiments. First, we demonstrated their efficacy in capturing volatile fatty acids emitted at a rendering plant when formulated as packed-bed filter cartridges. Secondly, we evaluated the potential to use aqueous PEI-f-CNC suspensions as a spray-based delivery method for VOC remediation. In both cases, the PEI-f-CNC formulations reduced detectable malodor VOCs by greater than 90%. The facile scaled synthesis of these materials and their excellent performance at VOC remediation suggest that they may emerge as a useful strategy for the remediation of VOCs associated with odor.

In this study we developed electrospun cellulose acetate nanofibers (CANFs) that were loaded with a model non-steroidal anti-inflammatory drug (NSAID) (ibuprofen, Ib) and coated with poly(acrylamide) (poly-AAm) hydrogel polymer using two consecutive steps: an electrospinning process followed by photopolymerization of AAm. Coated and non-coated CANF formulations were characterized by several microscopic and spectroscopic techniques to evaluate their physicochemical properties. An analysis of the kinetic release profile of Ib showed noticeable differences due to the presence or absence of the poly-AAm hydrogel polymer. Poly-AAm coating facilitated a constant release rate of drug as opposed to a more conventional burst release. The non-coated CANFs showed low cumulative drug release concentrations (ca. 35 and 83% at 5 and 10% loading, respectively). Conversely, poly-AAm coated CANFs were found to promote the release of drug (ca. 84 and 99.8% at 5 and 10% loading, respectively). Finally, the CANFs were found to be superbly cytocompatible.

Suture biomaterials are critical in wound repair by providing support to the healing of different tissues including vascular surgery, hemostasis, and plastic surgery. Important properties of a suture material include physical properties, handling characteristics, and biological response for successful performance. However, bacteria can bind to sutures and become a source of infection. For this reason, there is a need for new biomaterials for suture with antifouling properties. Here we report two types of cellulose fibers from coconut (Cocos nucifera) and sisal (Agave sisalana), which were purified with a chemical method, characterized, and tested in vitro and in vivo. According to SEM images, the cellulose fiber from coconut has a porous surface, and sisal has a uniform structure without internal spaces. It was found that the cellulose fiber from sisal has mechanical properties closer to silk fiber biomaterial using Ultimate Tensile Strength. When evaluating the cellulose fibers biodegradability, the cellulose from coconut showed a rapid weight loss compared to sisal. The antifouling test was negative, which demonstrated that neither possesses intrinsic microbicidal activity. Yet, a weak biofilm was formed on sisal cellulose fibers suggesting it possesses antifouling properties compared to cellulose from coconut. In vivo experiments using healthy mice demonstrated that the scarring and mechanical connection was like silk for both cellulose fibers. Overall, our results showed the potential use of cellulose fibers from vegetal for surgical sutures due to excellent mechanical properties, rapid degradation, and no bacterial adhesion.