Cellulose nanofibrils (CNF) were chemically functionalized with ethylamine groups using a quick, one-pot, water-based approach. Elemental analysis (EA) indicated the effective grafting of amine groups, with degrees of substitution consistent with previously reported values for amine-functionalized nanocellulose. Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR) indicates that the chemical modification was successful. It was corroborated by Infrared nanospectroscopy (AFM-IR) demonstrating distinctive vibrations associated with methylene and amine groups at both bulk and nanoscale levels. Atomic force microscopy (AFM) revealed a reduction in nanofibril diameter after chemical modification. X-ray diffraction (XRD) revealed that cellulose Iβ crystalline structure remained intact after modification. However, the crystallinity index decreased slightly due to the addition of ethylamine moieties and swelling during reaction. Thermogravimetry (TG) revealed enhanced thermal stability for modified CNF, as shown by higher degradation onset and maximum temperatures. Overall, this study presents an efficient and environmentally friendly approach for tailoring the surface chemistry of CNF while preserving their structural integrity, allowing them to be used in applications such as nanocomposites, coatings, colloidal systems, and filter membranes.
Technical cashew nutshell liquid (tCNSL), an abundant agro-industrial by-product of the cashew industry, represents a sustainable source of bioactive phenolic lipids with promising antioxidant and anti-inflammatory properties. In this study, tCNSL was used directly, without prior purification, and incorporated into soybean lecithin liposomes (tCNSL-LP), thereby providing a green, waste-to-value approach. The resulting formulations exhibited suitable physicochemical properties, including mean diameters of 552-624 nm, low polydispersity (PDI ≈ 0.3), high encapsulation efficiencies (79.5-88.0%), sustained release over 48 h, and good storage stability. tCNSL-LP protected polyunsaturated fatty acids from oxidative damage and showed no cytotoxicity up to 50 μM in keratinocytes, fibroblasts, and monocytes, whereas free tCNSL was significantly more toxic. Moreover, tCNSL-LP reduced oxidative stress-induced cell death, modulated inflammatory cytokine expression, promoted a pro-regenerative COL1A1/MMP1 profile, and restored keratinocyte migration under oxidative conditions. In the nematode Caenorhabditis elegans, reduced toxicity was revealed with the liposomal formulation of tCNSL with regard to pharyngeal pumping rate. These findings demonstrate that liposomal encapsulation influences safety, stability, and biological efficacy of tCNSL, allowing its valorisation as a sustainable ingredient for topical skin-care and wound-healing applications.
