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Author: Madeo, Lorenzo Francesco × Publisher: Basel : MDPI ×

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Now showing 1 - 3 of 3
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    Carbon Nanotubes Hybrid Hydrogels for Environmental Remediation: Evaluation of Adsorption Efficiency under Electric Field
    (Basel : MDPI, 2021) Cirillo, Giuseppe; Curcio, Manuela; Madeo, Lorenzo Francesco; Iemma, Francesca; De Filpo, Giovanni; Hampel, Silke; Nicoletta, Fiore Pasquale
    The performance of Carbon Nanotubes hybrid hydrogels for environmental remediation was investigated using Methylene Blue (MB), Rhodamine B (RD), and Bengal Rose (BR) as model contaminating dyes. An acrylate hydrogel network with incorporated CNT was synthesized by photo-polymerization without any preliminary derivatization of CNT surface. Thermodynamics, isothermal and kinetic studies showed favorable sorption processes with the application of an external 12 V electric field found to be able to influence the amount of adsorbed dyes: stronger interactions with cationic MB molecules (qexp and q12exp of 19.72 and 33.45 mg g−1, respectively) and reduced affinity for anionic RD (qexp and q12exp of 28.93 and 13.06 mg g−1, respectively) and neutral BR (qexp and q12exp of 36.75 and 15.85 mg g−1, respectively) molecules were recorded. The influence of pH variation on dyes adsorption was finally highlighted by reusability studies, with the negligible variation of adsorption capacity after five repeated sorption cycles claiming for the suitability of the proposed systems as effective sorbent for wastewater treatment.
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    Curcumin and Graphene Oxide Incorporated into Alginate Hydrogels as Versatile Devices for the Local Treatment of Squamous Cell Carcinoma
    (Basel : MDPI, 2022) Madeo, Lorenzo Francesco; Sarogni, Patrizia; Cirillo, Giuseppe; Vittorio, Orazio; Voliani, Valerio; Curcio, Manuela; Shai-Hee, Tyler; Büchner, Bernd; Mertig, Michael; Hampel, Silke
    With the aim of preparing hybrid hydrogels suitable for use as patches for the local treatment of squamous cell carcinoma (SCC)-affected areas, curcumin (CUR) was loaded onto graphene oxide (GO) nanosheets, which were then blended into an alginate hydrogel that was crosslinked by means of calcium ions. The homogeneous incorporation of GO within the polymer network, which was confirmed through morphological investigations, improved the stability of the hybrid system compared to blank hydrogels. The weight loss in the 100–170 °C temperature range was reduced from 30% to 20%, and the degradation of alginate chains shifted to higher temperatures. Moreover, GO enhanced the stability in water media by counteracting the de-crosslinking process of the polymer network. Cell viability assays showed that the loading of CUR (2.5% and 5% by weight) was able to reduce the intrinsic toxicity of GO towards healthy cells, while higher amounts were ineffective due to the antioxidant/prooxidant paradox. Interestingly, the CUR-loaded systems were found to possess a strong cytotoxic effect in SCC cancer cells, and the sustained CUR release (~50% after 96 h) allowed long-term anticancer efficiency to be hypothesized.
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    Release of Bioactive Molecules from Graphene Oxide-Alginate Hybrid Hydrogels: Effect of Crosslinking Method
    (Basel : MDPI, 2023) Madeo, Lorenzo Francesco; Curcio, Manuela; Iemma, Francesca; Nicoletta, Fiore Pasquale; Hampel, Silke; Cirillo, Giuseppe
    To investigate the influence of crosslinking methods on the releasing performance of hybrid hydrogels, we synthesized two systems consisting of Graphene oxide (GO) as a functional element and alginate as polymer counterpart by means of ionic gelation (physical method, 𝐻𝑃𝐴−𝐺𝑂) and radical polymerization (chemical method, 𝐻𝐶𝐴−𝐺𝑂). Formulations were optimized to maximize the GO content (2.0 and 1.15% for 𝐻𝑃𝐴−𝐺𝑂 and 𝐻𝐶𝐴−𝐺𝑂, respectively) and Curcumin (CUR) was loaded as a model drug at 2.5, 5.0, and 7.5% (by weight). The physico-chemical characterization confirmed the homogeneous incorporation of GO within the polymer network and the enhanced thermal stability of hybrid vs. blank hydrogels. The determination of swelling profiles showed a higher swelling degree for 𝐻𝐶𝐴−𝐺𝑂 and a marked pH responsivity due to the COOH functionalities. Moreover, the application of external voltages modified the water affinity of 𝐻𝐶𝐴−𝐺𝑂, while they accelerated the degradation of 𝐻𝑃𝐴−𝐺𝑂 due to the disruption of the crosslinking points and the partial dissolution of alginate. The evaluation of release profiles, extensively analysed by the application of semi-empirical mathematical models, showed a sustained release from hybrid hydrogels, and the possibility to modulate the releasing amount and rate by electro-stimulation of 𝐻𝐶𝐴−𝐺𝑂.