Chitosan-silica Hybrid Research Articles

A review of the prospects, efficacy and sustainability of nanotechnology-based approaches for oil spill remediation.

Numerous marine oil spill incidents and their environmental catastrophe have raised the concern of the research community and environmental agencies on the topic of the offshore crude oil spill. The oil transport through oil tankers and pipelines has further aggravated the risk of the oil spill. This has led to the necessity to develop an effective, environment-friendly, versatile oil spill clean-up strategy. The current review article analyses various nanotechnology-based methods for marine oil spill clean-up, focusing on their recovery rate, reusability and cost. The authors weighed the three primary factors recovery, reusability and cost distinctively for the analysis based on their significance in various contexts. The findings and analysis suggest that magnetic nanomaterials and nano-sorbent have been the most effective nanotechnology-based marine oil spill remediation techniques, with the magnetic paper based on ultralong hydroxyapatite nanowires standing out with a recovery rate of over 99%. The chitosan-silica hybrid nano-sorbent and multi-wall carbon nanotubes are also promising options with high recovery rates of up to 95-98% and the ability to be reused multiple times. Although the photocatalytic biodegradation approach and the nano-dispersion method do not offer benefits for recovery or reusability, they can nevertheless help lessen the negative ecological effects of marine oil spills. Therefore, careful evaluation and selection of the most appropriate method for each marine oil spill situation is crucial. The current review article provides valuable insights into the current state of nanotechnology-based marine oil spill clean-up methods and their potential applications.

Chitosan-Silica Composite Aerogel for the Adsorption of Cupric Ions.

A chitosan-silica hybrid aerogel was synthesized and presented as a potential adsorbent for the purification of cupric ion-contaminated media. The combination of the organic polymer (chitosan), which can be obtained from fishery wastes, with silica produced a mostly macroporous material with an average pore diameter of 33 µm. The obtained aerogel was extremely light (56 kg m-3), porous (96% porosity, 17 cm3 g-1 pore volume), and presented a Brunauer-Emmett-Teller surface area (SBET) of 2.05 m2 g-1. The effects of solution pH, aerogel and Cu(II) concentration, contact time, and counterion on cupric removal with the aerogel were studied. Results showed that the initial pH of the cation-containing aqueous solution had very little influence on the removal performance of this aerogel. According to Langmuir isotherm, this material can remove a maximum amount of ca. 40 mg of cupric ions per gram and the kinetic data showed that the surface reaction was the rate-limiting step and equilibrium was quickly reached (in less than one hour). Thus, the approach developed in this study enabled the recovery of waste for the preparation of a novel material, which can be efficiently reused in a new application, namely water remediation.

Chitosan-Silica Hybrid Biomaterials for Bone Tissue Engineering: A Comparative Study of Xerogels and Aerogels.

Chitosan (CS) is a natural biopolymer that shows promise as a biomaterial for bone-tissue regeneration. However, because of their limited ability to induce cell differentiation and high degradation rate, among other drawbacks associated with its use, the creation of CS-based biomaterials remains a problem in bone tissue engineering research. Here we aimed to reduce these disadvantages while retaining the benefits of potential CS biomaterial by combining it with silica to provide sufficient additional structural support for bone regeneration. In this work, CS-silica xerogel and aerogel hybrids with 8 wt.% CS content, designated SCS8X and SCS8A, respectively, were prepared by sol-gel method, either by direct solvent evaporation at the atmospheric pressure or by supercritical drying in CO2, respectively. As reported in previous studies, it was confirmed that both types of mesoporous materials exhibited large surface areas (821 m2g-1-858 m2g-1) and outstanding bioactivity, as well as osteoconductive properties. In addition to silica and chitosan, the inclusion of 10 wt.% of tricalcium phosphate (TCP), designated SCS8T10X, was also considered, which stimulates a fast bioactive response of the xerogel surface. The results here obtained also demonstrate that xerogels induced earlier cell differentiation than the aerogels with identical composition. In conclusion, our study shows that the sol-gel synthesis of CS-silica xerogels and aerogels enhances not only their bioactive response, but also osteoconduction and cell differentiation properties. Therefore, these new biomaterials should provide adequate secretion of the osteoid for a fast bone regeneration.

Thermodynamic study of the adsorption of Cd2+ and Ni2+ onto chitosan – Silica hybrid aerogel from aqueous solution

Adsorption studies have been conducted on aqueous solution to investigate the effect of temperature on the sorption of Cd2+ and Ni2+ by Chitosan-silica hybrid aerogel [(CS)hA], which was developed using a blend of components from crab exoskeleton and bamboo biomass and synthesized using sol–gel method. The application of this derived aerogel for clean-up of water bodies polluted with heavy metals at varying temperatures was undertaken with a view to establish its effectiveness. The studied temperatures were 301 K, 308 K, 318 K, 328 K and 338 K at pH 3 and contact time of 180 mins and 60 mins for Cd2+ and Ni2+, respectively. Data obtained were subjected to Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherm models which were used to evaluate the adsorption process. Langmuir Isotherm model proved to be the best fit in interpreting the adsorption process with the maximum Cd2+ sorption values within 57.14 to 57.80 mg g−1 while Ni2+ sorption values lie between 52.08 and 58.82 mg g−1. The effect of enthalpy (ΔH°), entropy (ΔS°) and Gibbs free energy (ΔG°) on the sorption of Cd2+ and Ni2+ by the derived aerogel were also deduced. The process is spontaneous, exothermic with the studied ions well aligned on the derived aerogel surface.

Synthesis and Optimization of Superhydrophilic-Superoleophobic Chitosan-Silica/HNT Nanocomposite Coating for Oil-Water Separation Using Response Surface Methodology.

In this current study, facile, one-pot synthesis of functionalised nanocomposite coating with simultaneous hydrophilic and oleophobic properties was successfully achieved via the sol–gel technique. The synthesis of this nanocomposite coating aims to develop a highly efficient, simultaneously oleophobic-hydrophilic coating intended for polymer membranes to spontaneously separate oil-in-water emulsions, therefore, mitigating the fouling issue posed by an unmodified polymer membrane. The simultaneous hydrophilicity-oleophobicity of the nanocoating can be applied onto an existing membrane to improve their capability to spontaneously separate oil-in-water substances in the treatment of oily wastewater using little to no energy and being environmentally friendly. The synthesis of hybrid chitosan–silica (CTS-Si)/halloysite nanotube (HNT) nanocomposite coating using the sol–gel method was presented, and the resultant coating was characterised using FTIR, XPS, XRD, NMR, BET, Zeta Potential, and TGA. The wettability of the nanocomposite coating was evaluated in terms of water and oil contact angle, in which it was coated onto a polymer substrate. The coating was optimised in terms of oil and water contact angle using Response Surface Modification (RSM) with Central Composite Design (CCD) theory. The XPS results revealed the successful grafting of organosilanes groups of HNT onto the CTS-Si denoted by a wide band between 102.6–103.7 eV at Si2p. FTIR spectrum presented significant peaks at 3621 cm−1; 1013 cm−1 was attributed to chitosan, and 787 cm−1 signified the stretching of Si-O-Si on HNT. 29Si, 27Al, and 13H NMR spectroscopy confirmed the extensive modification of the particle’s shells with chitosan–silica hybrid covalently linked to the halloysite nanotube domains. The morphological analysis via FESEM resulted in the surface morphology that indicates improved wettability of the nanocomposite. The resultant colloids have a high colloid stability of 19.3 mV and electrophoretic mobility of 0.1904 µmcm/Vs. The coating recorded high hydrophilicity with amplified oleophobic properties depicted by a low water contact angle (WCA) of 11° and high oil contact angle (OCA) of 171.3°. The optimisation results via RSM suggested that the optimised sol pH and nanoparticle loadings were pH 7.0 and 1.05 wt%, respectively, yielding 95% desirability for high oil contact angle and low water contact angle.

A high-performance solid electrolyte assisted with hybrid biomaterials for lithium metal batteries

The demand for high safety lithium batteries has led to the rapid development of solid electrolytes. However, some inherent limitations of solid polymer electrolytes (SPEs) impede them achieving commercial value. In this work, a novel polyethylene oxide (PEO)-based solid electrolyte is reported. For the first time, biomaterial-based chitosan-silica (CS) hybrid particles serve as fillers, which can interact with polymer matrix to significantly improve the electrochemical performance. The optimized polymer electrolyte exhibits a maximum ion conductivity of 1.91 × 10−4 S·cm−1 at 30 °C when the mass ratio of PEO and CS is 4:1 (PCS4). All-solid-state LiFePO4|PCS4|Li cells deliver a high coulombic efficiency and stable cycling performance, remaining an excellent capacity of more than 96.2 % after 150 cycles. Furthermore, the wide electrochemical window (5.4 V) and steady interfacial stability provide the possibility for high-voltage batteries applications. NCM811|| Li cells are assembled and display reliable charge and discharge cycle properties.

Nickel Sorption onto Chitosan - Silica Hybrid Aerogel from Aqueous Solution

The utilization and efficiency of agricultural waste-derived chitosan-silica hybrid aerogel “(CS)hA” on nickel removal from aqueous solution was examined and optimum parameters for pH, contact time, and initial ion concentration were determined during batch sorption system studies. Metal recovery was performed on the adsorbent using separately dilute concentrations of hydrochloric acid, acetic acid, ammonia, and sodium hydroxide solutions as eluents. The results generated were analyzed from kinetic and isotherm studies. The maximum Ni2+ adsorption of 99.78 % was established at 60 min and pH 3 in this study. The batch studies revealed that the percentage of nickel ion removal by the adsorbent decreased along with an increase in the initial Ni2+ ions concentration. The pseudo-second-order, the best fit of the kinetic model, has the values of its correlation coefficient “R2” ranging from 0.9 to 1, whereas the Langmuir model which had the maximum monolayer adsorption capacity of 85.84 mg g-1, was the best isotherm in interpreting the sorption process and the calculated separation factor was higher than 0 but less than 1. Dilute hydrochloric acid (0.1 M) was the best eluent in removing bound nickel ions (55.63 %) from (CS)hA.

Development of mangiferin loaded chitosan-silica hybrid scaffolds: Physicochemical and bioactivity characterization

Development of hybrid materials with molecular structure of organic-inorganic co-network is a promising method to enhance the stability and mechanical properties of biopolymers. Chitosan-silica hybrid nanocomposite scaffolds loaded with mangiferin, a plant-derived active compound possessing several bioactivities, were fabricated using the sol-gel synthesis and the freeze-drying processes. Investigation on the physicochemical and mechanical properties of the fabricated scaffolds showed that their properties can be improved and tailored by the formation of 3-dimensional crosslinked network and the addition of ZnO nanoparticles. The scaffolds possessed porosity, fluid uptake, morphology, thermal properties and mechanical strength suitable for bone tissue engineering application. Investigation on the biomineralization and cell viability indicated that the inclusion of bioactive mangiferin further promote potential use of the hybrid nanocomposite scaffolds in guided bone regeneration application.

Formation mechanisms of chitosan-silica hybrid materials and its performance as solid support for KR-12 peptide adsorption: Impact on KR-12 antimicrobial activity and proteolytic stability

Chitosan-silica materials offer a specific environment for the adsorption of biofunctional molecules, such as the antimicrobial peptide KR-12. The objective here is to rationalize the changes in the physicochemical properties of these chitosan-silica materials in function of the synthesis pH, using 0.02w/v % chitosan as catalyst and aggregation agent and, to correlate these characteristics with the loading/delivery and activity/stability of KR-12 antimicrobial peptide. The CS-6 material, prepared at pH 6, exhibits higher surface area (745m2/g) and total pore volume (0.58cm3/g) due to the lower incorporation of chitosan swollen chains (9.36wt %). Higher pHs produced denser materials (CS-7 and CS-8) with higher entangled chitosan incorporated (> 17wt%). Adsorption of KR-12 peptide was found to take two different mechanisms depending on the chitosan-silica support, Langmuir-type for CS-6 material and Freundlich-type for CS-7 and CS-8 materials. According to the KR-12 release profiles, more hydrophobic interactions were observed in the CS-6 material exposing Lys and Arg residues from the peptide towards the material surface. This was correlated with the higher antimicrobial activity of this material against S. aureus strain (MIC=128μg/mL). Additionally, the KR-12 peptide adsorbed in the CS-6 hybrid support is 34 % more protected from the proteolytic action of α-chymotrypsin than the free one. In conclusion, the proposed models of different porous environments in the studied chitosan-silica materials supports the KR-12 peptide loading/delivery mechanisms, leading to biofunctionalized solid antimicrobial materials exhibiting proteolytic stability. This knowledge is useful for designing new antibacterial materials for biomedical applications.

Homogeneous phase synthesis of chitosan silica hybrid materials in ionic liquid medium and adsorption of Fe(III) from aqueous solutions

Two chitosan silica hybrid materials were prepared by a two-step process in 78–84% yields using the homogeneous phase reaction of 3-(triethoxysilyl)propyl isocyanate with chitosan dissolved in 1-n-butyl-3-methylimidazolium chloride ionic liquid (∼10% w/w), which was followed by NH4OH catalyzed hydrolysis of triethoxysilyl groups and then sol-gel process. These new hybrid materials were shown to adsorb up to about 95% of Fe3+ from 5 × 10−4 M aqueous solution at room temperature in 24 h.

Synthesis, Characterization, and In Vitro Drug Delivery of Chitosan-Silica Hybrid Microspheres for Bone Tissue Engineering

Chitosan-silica (CS-SiO2) hybrid microspheres were prepared through the combined process of sol-gel and emulsification-crosslinking. Their composition, morphology, in vitro bioactivity, and drug release behavior were investigated. The results showed that, when 20 wt% SiO2 was incorporated, the as-prepared CS-SiO2 hybrid microspheres exhibited a regular spherical shape, a high dispersity, and a uniform microstructure. Their average particle diameter was determined to be about 24.0 μm. The in situ deposited inorganic phase of the hybrid microspheres was identified as amorphous SiO2, and its actual content was determined by the TG analysis. As compared with the pure chitosan microspheres, the CS-SiO2 hybrid microspheres displayed a greatly improved in vitro bioactivity. Vancomycin hydrochloride (VH) was selected as a model drug. It was demonstrated that the CS-SiO2 hybrid microspheres presented a good capacity for both loading and sustained release of VH. Moreover, the increase of the SiO2 content efficiently slowed down the drug release rate of the CS-SiO2 hybrid microspheres.

Engineered dressing of hybrid chitosan-silica for effective delivery of keratin growth factor and acceleration of wound healing

Biological dressings composed of multi-components including extracellular matrix (ECM) materials and therapeutic agents for facilitating wound healing have been actively reported. To improve the wound healing ability of chitosan dressing, sol-gel derived silica was incorporated with chitosan and this chitosan-silica hybrid dressing was combined with keratinocyte growth factor (KGF) in this study. Such hybrid dressing showed higher efficacy of KGF adsorption than pure chitosan dressing due to its porous structure and hydrophilic character. The hybrid dressing showed sustainable release profile for KGF. The delivered-KGF improved keratinocyte activities such as attachment and proliferation. In vivo animal test using excisional wound model revealed that such dressing could facilitate skin regeneration. However, the tissue regeneration process was different depending on combinatorial components in the dressing. Chitosan dressing incorporated with KGF improved the wound healing process compared to chitosan dressing without KGF. The chitosan-silica hybrid dressing combined with KGF showed the best wound healing process.

In-vitro blood and vascular compatibility of sirolimus-eluting organic/inorganic hybrid stent coatings

The surface characteristics of coronary stents play a pivotal role in inhibiting in-stent restenosis and late-stent thrombosis. In this study, a sol-gel-derived silica xerogel-chitosan hybrid coating was applied to Co-Cr stent and was reported, for the first time, as a biocompatible drug delivery tool in vascular stent application. A dense and uniform chitosan-silica xerogel hybrid coating (<1-μm thick) was applied on bare Co-Cr material. Sirolimus was well incorporated into the hybrid coatings without re-crystallization. The chitosan-silica hybrid coating with 30 wt% silica xerogel showed better mechanical stability and good adhesive strength without any cracking or delamination. The chitosan-silica hybrid coated Co-Cr surface exhibited significantly improved wettability and corrosion resistance compared to the chitosan coated Co-Cr surface. In addition, the hybrid coating layer enabled efficient loading of sirolimus, owing to the unique mesoporous structure of silica xerogel, which further allowed the sustained release of sirolimus over 3 weeks. In-vitro tests with human umbilical cord vein endothelial cells and blood platelets confirmed that the chitosan-silica hybrid coating had excellent cytocompatibility and hemocompatibilty. Thus, this study demonstrated that the chitosan-silica hybrid material is a promising material for coating coronary stents, with minimal risk of in-stent restenosis and thrombogenicity.

Adsorption of Cd (II) on chitosan–silica hybrid aerogel from aqueous solution

Abstract Chitosan–silica hybrid aerogel was applied in aqueous solution for Cd 2 + removal. The resulting aerogel was subjected to pH, contact time, and metal recovery studies. Data obtained was subjected to kinetic and isotherm studies. The optimum conditions for Cd 2 + adsorption was established to be at a pH of 3 and contact time of 180 min. Pseudo second order kinetic model with R2 value above 0.9 was best fit to the study whereas Langmuir model is the preferred isotherm for the data as the dimensionless constant separation factor calculated fell between 0 and 1. Parameters influencing the adsorption process were also investigated.

Synthesis and characterization of Chitosan–silica hybrid aerogel using sol-gel method

Chitosan–silica hybrid aerogel [(CS)hA] was prepared using sol-gel method by combining an inorganic network in the presence of an organic polymer. Chitosan biopolymer and silica (SiO2) which are obtained from agricultural waste of crab shell and bamboo leaves are the primary precursors used in the sol-gel reaction and hexamethyldisiloxane applied for hydrophobicity. The derived aerogel has been characterized using Fourier transform infrared (FTIR), scanning electron microscope (SEM), energy dispersive X-ray (EDX), and thermogravimetric analysis (TGA). Sears method was used to determine surface area. The FTIR spectrum shows presence of organic and inorganic entities which are also seen on the EDX chart. TGA provides information on the thermal stability of the derived aerogel. The SEM analysis shows clearly the surface morphology and roughness of (CS)hA. The calculated pore volume, bulk density, surface area, and porosity is 0.286 cm3 g−1, 0.441 g cm−3, 237.4 m2 g−1 and 0.126.

Fabrication of novel bioactive hydroxyapatite-chitosan-silica hybrid scaffolds: Combined the sol-gel method with 3D plotting technique

Sol-gel derived organic/inorganic hybrids, in which organic and inorganic components form co-networks at the molecular level, have demonstrated great potential for providing improved mechanical properties and biological functions in tissue engineering applications. Here, a novel bioactive hydroxyapatite-chitosan-silica hybrid (HA-CSH) scaffold was successfully fabricated by combining the sol-gel method and 3D plotting technique. Physiochemical characterization confirmed that chitosan was hybridized homogeneously with the inorganic phase on nanoscale. The obtained scaffolds possessed precisely controllable and interconnected porous structures. The nano-sized HA formed in situ and dispersed uniformly in the hybrid network, which reduced the water absorption and increased the mechanical strength of the hybrid scaffold under humidity condition as compared to chitosan-silica hybrid (CSH) scaffold. Compression tests showed that the 3D plotted hybrid scaffolds under wet conditions had compressive strengths of 10–13 MPa and elastic moduli of 21–27 MPa and thus met the mechanical requirements of human trabecular bone. Studies on the mineralization process under simulated body fluid (SBF) conditions confirmed that the introduction of HA obviously increased the biological activity of hybrid scaffolds. In vitro cell results indicated that the HA-CSH scaffold not only supported adhesion and proliferation of mouse bone mesenchymal stem cells (mBMSCs), but also improved the osteoinductivity. The alkaline phosphatase activity and mineral deposition on the HA-CSH scaffold were higher than those on the CSH scaffold. These results suggested that the 3D plotted HA-CSH scaffold may be a promising bioactive material for bone tissues regeneration.

Chitosan-Silica Hybrid Composites for Removal of Sulfonated Azo Dyes from Aqueous Solutions.

In this study, the influence of the chitosan immobilization method on the properties of final hybrid materials was performed. Chitosan was immobilized on the surface of mesoporous (ChS2) and fumed silica (ChS3) by physical adsorption and the sol-gel method (ChS1). It was found that physical immobilization of chitosan allows to obtain hybrid composites (ChS) with a homogeneous distribution of polymer on the surface, relatively wide pores, and specific surface area of about 170 m2/g, pHPZC = 5.7 for ChS3 and 356 m2/g and pHPZC = 6.0 for ChS2. The microporous chitosan-silica material with a specific surface area of 600 m2/g and a more negatively charged surface (pHPZC = 4.2) was obtained by the sol-gel reaction. The mechanisms of azo dye adsorption were studied, and the correlation with the composite structure was distinguished. The generalized Langmuir equation and its special cases, that is, Langmuir-Freundlich and Langmuir equations, were applied for the analysis of adsorption isotherm data. The adsorption study showed that physically adsorbed chitosan (ChS1 and ChS2) on a silica surface has a higher sorption capacity, for example, 0.48 mmol/g for the acid red 88 (AR88) dye (ChS2) and 0.23 mmol/g for the acid orange 8 (AO8) dye (ChS1), compared to the composite obtained by the sol-gel method [ChS1, 0.05 mmol/g for the AO8 dye]. For a deeper understanding of the behavior of immobilized chitosan in the adsorption processes, various kinetic equations were applied: first-order, second-order, mixed 1,2-order (MOE), multiexponential, and fractal-like MOE as well as intraparticle and pore diffusion model equations. In the case of AO8 dye, the adsorption rates were differentiated for three composites: for ChS3, 50% of the dye was removed from the solution after merely 5 min and almost 90% after 80 min. The slowest adsorption process controlled by the diffusion rate of dye molecules into the internal space of the pore structure was found for ChS1 (225 min halftime). In the case of ChS2, the rates for various dyes change in the following order: acid orange (AO7) > orange G (OG) > acid red 1 (AR1) > AR88 > AO8 (halftimes: 10.5 < 15.7 < 23.7 < 34.9 < 42.9 min).

Acceleration of the healing process of full-thickness wounds using hydrophilic chitosan-silica hybrid sponge in a porcine model.

In this study, we evaluated the surface characterization of a novel chitosan-silica hybridized membrane and highlighted the substantial role of silica in the wound environment. The chemical coupling of chitosan and silica resulted in a more condensed network compared with pure chitosan, which was eventually able to stably maintain its framework, particularly in the wet state. In addition, we closely observed the wound-healing process along with the surface interaction between chitosan-silica and the wound site using large-surface-area wounds in a porcine model. Our evidence indicates that chitosan-silica exerts a synergetic effect of both materials to promote a remarkable wound-healing process. In particular, the silica in chitosan-silica accelerated wound closure including wound contraction, and re-epithelialization via enhancement of cell recruitment, epidermal maturity, neovascularization, and granulation tissue formation compared with pure chitosan and other commercial dressing materials. This advanced wound dressing material may lead to effective treatment for problematic cutaneous wounds and can be further applied for human skin regeneration.

New N-guanidinium chitosan/silica ionic microhybrids as efficient adsorbent for dye removal from waste water

N-guanidinium chitosan acetate, a new chitosan derivative, was prepared via direct guanylation reaction between chitosan and cyanamide in the presence of scandium (III) triflate. Treatment of N-guanidinium chitosan acetate with 3-(trihydroxysilyl)-1-propanesulphonic acid followed by sol-gel reaction allowed accessing N-guanidinium chitosan silica hybrid material. The new ionic microhybrid was characterized using 13C and 29Si solid state NMR, IR spectroscopy, scanning electron microscopy and thermogravimetry. Further studies in the area of separation indicated very high adsorption capacity for cationic dyes such as methylene blue (MB), with capacities up to 935 mg/g. The adsorption kinetics can accurately be described by pseudo second-order model. Equilibrium adsorption data showed a better fit with Langmuir adsorption isotherm model. Recycling test showed that the ionic microhybrid can be reused in at least five adsorption-desorption cycles. These results open new perspectives and possibilities for the design of novel hybrid adsorbents for industrial and environmental applications.

Chitosan-silica hybrid nanosorbents for oil removal from water

Water pollution caused by oil spills is an environmental problem that raises concerns all over the world. Sorbent materials are of great importance for the removal of the remained oil after skimming operation. Nevertheless owing to reduced size, most sorbents are difficult to collect from water and therefore there is need to develop effective oil sorbents that could be easily separated from aquatic environments. Herein new magnetic nanosorbents composed of magnetite nanoparticles functionalized with chitosan hybrid siliceous shells were successfully prepared using a one-step sol–gel encapsulation method. As a proof of concept, these nanosorbents were tested in the magnetically assisted removal of non-polar organic solvents from water. The characterization of the materials using FTIR spectroscopy, solid-state 29Si and 13C NMR spectroscopy and elemental microanalysis confirmed the extensive modification of the particles’ shells with chitosan molecules covalently linked to the siliceous domains. These hybrid particles could efficiently adsorb various non-polar organic solvents from water, a behavior that was ascribed to the presence of chitosan macromolecules grafted at the surface of the particles. This is a new type of sorbent with potential application in the removal of oil from water using magnetic separation technologies.