Submit to Polymers Review for Polymers Propose a Special Issue

Journal Browser

► Journal Browser

Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications

Special Issue Editors
Special Issue Information
Keywords
Published Papers

A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Polymer Applications".

Deadline for manuscript submissions: closed (31 October 2020) | Viewed by 47587

Share This Special Issue

Special Issue Editors

Dr. Carlos A. García-González

E-Mail Website1 Website2
Guest Editor

Department of Pharmacology, Pharmacy and Pharmaceutical Technology, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
Interests: aerogels; supercritical fluids; regenerative medicine; pharmaceutical technology; 3D-bioprinting; porous materials; scaffolds; biomedical applications
Special Issues, Collections and Topics in MDPI journals

Dr. Luísa Durães

E-Mail Website
Guest Editor

Chemical Process Engineering and Forest Products Research Centre, Department of Chemical Engineering, University of Coimbra, 3000-370 Coimbra, Portugal
Interests: aerogels; nanoparticles; sol-gel; soft-solution synthesis; functional nanomaterials; environmental remediation; thermal insulation
Special Issues, Collections and Topics in MDPI journals

Prof. Dr. Tatiana Budtova

E-Mail Website
Guest Editor

MINES ParisTech, PSL Research University, Center for Materials Forming-CEMEF, UMR CNRS 7635, CS 10207, 06904 Sophia Antipolis, France
Interests: polymer solution; gels and aerogels; complex fluids; bioplastics; composites with natural fibers

Prof. Dr. Falk Liebner

E-Mail Website
Guest Editor

1. Institute for Chemistry of Renewable Resources, Department of Chemistry, University of Natural Resources and Life Sciences Vienna, 3430 Tulln, Austria
2. Department of Chemistry, Aveiro Institute of Materials (CICECO), University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
Interests: biopolymers; cellulose; lignin; biobased gels and porous materials; aerogels; supercritical carbon dioxide; green chemistry

Prof. Dr. Urszula Stachewicz

E-Mail Website
Guest Editor

Faculty of Metals Engineering and Industrial Computer Science, AGH Univeristy of Science and Technology, Krakow, Poland
Interests: electrospinning; electrospray; fibers, scaffolds; membranes; porous mats; 3D tomography; FIB-SEM; microscopy; wetting; nanomechanics; surface properties; biomimetics
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Aerogels are unique nanostructured porous materials with special properties adapted to fit certain advanced applications. Namely, the biomedical and environmental fields are two emerging market opportunities for these materials.
Aerogel-based materials can be used in biomedical applications such as drug carriers, synthetic bone grafts for regenerative medicine and advanced wound dressings. For environmental applications, heat and sound insulators, as well as absorbents, adsorbents, sensors and catalysts for wastewater treatment and for air and water pollutants detection are among the uses being explored for aerogels.
Technological developments in terms of novel designs, processes, modelling tools, characterization techniques and uses for aerogels should be aligned to boost the progresses on the topic. This Special Issue aims at showing the most recent scientific-technological advances in aerogels on a wide range of fundamental topics and applied for biomedical and environmental uses.
This Special Issue is an initiative of the AERoGELS (CA18125 - Advanced Engineering and Research of aeroGels for Environment and Life Sciences) Action (https://cost-aerogels.eu) by COST (European Cooperation in Science and Technology) that aims to boost the development of aerogels for biomedical and environmental applications by setting up a multidisciplinary knowledge-based network from technological, scientific and market points of view.

Prof. Dr. Carlos A. García-González
Prof. Dr. Luísa Durães
Prof. Dr. Tatiana Budtova
Prof. Dr. Falk Liebner
Prof. Dr. Urszula Stachewicz
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Polymers is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

aerogels
modelling
nanostructured materials
bio-based aerogels
advanced materials
composites
process engineering
scale-up
supercritical drying
health risk assessment

Published Papers (13 papers)

Download All Papers

Research

Jump to: Review

15 pages, 3758 KiB

Open AccessArticle

Nerve Response to Superelastic Shape Memory Polyurethane Aerogels

by Martina Rodriguez Sala, Omar Skalli, Nicholas Leventis and Firouzeh Sabri

Polymers 2020, 12(12), 2995; https://doi.org/10.3390/polym12122995 - 15 Dec 2020

Cited by 12 | Viewed by 2370

Abstract

We have previously shown the suitability of aerogels as scaffolds for neuronal cells. Here, we report on the use of superelastic shape memory polyurethane aerogels (SSMPA). SSMPA have a distinctly different stiffness than previously reported aerogels. The soft and deformable nature of SSMPA allowed for radial compression of the aerogel induced by a custom designed apparatus. This radial compression changed the pore diameter and surface roughness (Sa) of SSMPA, while maintaining similar stiffness. Two varieties of SSMPA were used, Mix-14 and Mix-18, with distinctly different pore diameters and Sa. Radial compression led to a decreased pore diameter, which, in turn, decreased the Sa. The use of custom designed apparatus and two types of SSMPA allowed us to examine the influence of stiffness, pore size, and Sa on the extension of processes (neurites) by PC12 neuronal cells. PC12 cells plated on SSMPA with a higher degree of radial compression extended fewer neurites per cell when compared to other groups. However, the average length of the neurites was significantly longer when compared to the unrestricted group and to those extended by cells plated on SSMPA with less radial compression. These results demonstrate that SSMPA with 1.9 µm pore diameter, 1.17 µm Sa, and 203 kPa stiffness provides the optimum combination of physical parameters for nerve regeneration. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

22 pages, 11123 KiB

Open AccessArticle

Hydroxyl Groups Induce Bioactivity in Silica/Chitosan Aerogels Designed for Bone Tissue Engineering. In Vitro Model for the Assessment of Osteoblasts Behavior

by Antonio Perez-Moreno, María de las Virtudes Reyes-Peces, Deseada María de los Santos, Gonzalo Pinaglia-Tobaruela, Emilio de la Orden, José Ignacio Vilches-Pérez, Mercedes Salido, Manuel Piñero and Nicolás de la Rosa-Fox

Polymers 2020, 12(12), 2802; https://doi.org/10.3390/polym12122802 - 26 Nov 2020

Cited by 19 | Viewed by 2392

Abstract

Silica (SiO₂)/chitosan (CS) composite aerogels are bioactive when they are submerged in simulated body fluid (SBF), causing the formation of bone-like hydroxyapatite (HAp) layer. Silica-based hybrid aerogels improve the elastic behavior, and the combined CS modifies the network entanglement as a crosslinking biopolymer. Tetraethoxysilane (TEOS)/CS is used as network precursors by employing a sol-gel method assisted with high power ultrasound (600 W). Upon gelation and aging, gels are dried in supercritical CO₂ to obtain monoliths. Thermograms provide information about the condensation of the remaining hydroxyl groups (400–700 °C). This step permits the evaluation of the hydroxyl group’s content of 2 to 5 OH nm⁻². The formed Si-OH groups act as the inductor of apatite crystal nucleation in SBF. The N₂ physisorption isotherms show a hysteresis loop of type H3, characteristic to good interconnected porosity, which facilitates both the bioactivity and the adhesion of osteoblasts cells. After two weeks of immersion in SBF, a layer of HAp microcrystals develops on the surface with a stoichiometric Ca/P molar ratio of 1.67 with spherulite morphology and uniform sizes of 6 μm. This fact asserts the bioactive behavior of these hybrid aerogels. Osteoblasts are cultured on the selected samples and immunolabeled for cytoskeletal and focal adhesion expression related to scaffold nanostructure and composition. The initial osteoconductive response observes points to a great potential of tissue engineering for the designed composite aerogels. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

17 pages, 2226 KiB

Open AccessArticle

Ca-Zn-Ag Alginate Aerogels for Wound Healing Applications: Swelling Behavior in Simulated Human Body Fluids and Effect on Macrophages

by Claudia Keil, Christopher Hübner, Constanze Richter, Sandy Lier, Lars Barthel, Vera Meyer, Raman Subrahmanyam, Pavel Gurikov, Irina Smirnova and Hajo Haase

Polymers 2020, 12(11), 2741; https://doi.org/10.3390/polym12112741 - 18 Nov 2020

Cited by 19 | Viewed by 3039

Abstract

Chronic non-healing wounds represent a substantial economic burden to healthcare systems and cause a considerable reduction in quality of life for those affected. Approximately 0.5–2% of the population in developed countries are projected to experience a chronic wound in their lifetime, necessitating further developments in the area of wound care materials. The use of aerogels for wound healing applications has increased due to their high exudate absorbency and ability to incorporate therapeutic substances, amongst them trace metals, to promote wound-healing. This study evaluates the swelling behavior of Ca-Zn-Ag-loaded alginate aerogels and their metal release upon incubation in human sweat or wound fluid substitutes. All aerogels show excellent liquid uptake from any of the formulas and high liquid holding capacities. Calcium is only marginally released into the swelling solvents, thus remaining as alginate bridging component aiding the absorption and fast transfer of liquids into the aerogel network. The zinc transfer quota is similar to those observed for common wound dressings in human and animal injury models. With respect to the immune regulatory function of zinc, cell culture studies show a high availability and anti-inflammatory activity of aerogel released Zn-species in RAW 264.7 macrophages. For silver, the balance between antibacterial effectiveness versus cytotoxicity remains a significant challenge for which the alginate aerogels need to be improved in the future. An increased knowledge of the transformations that alginate aerogels undergo in the course of the fabrication as well as during wound fluid exposure is necessary when aiming to create advanced, tissue-compatible aerogel products. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

24 pages, 5021 KiB

Open AccessArticle

Chitosan-GPTMS-Silica Hybrid Mesoporous Aerogels for Bone Tissue Engineering

by María V. Reyes-Peces, A. Pérez-Moreno, Deseada María de-los-Santos, María del Mar Mesa-Díaz, Gonzalo Pinaglia-Tobaruela, Jose Ignacio Vilches-Pérez, Rafael Fernández-Montesinos, Mercedes Salido, Nicolás de la Rosa-Fox and Manuel Piñero

Polymers 2020, 12(11), 2723; https://doi.org/10.3390/polym12112723 - 17 Nov 2020

Cited by 25 | Viewed by 4256

Abstract

This study introduces a new synthesis route for obtaining homogeneous chitosan (CS)-silica hybrid aerogels with CS contents up to 10 wt%, using 3-glycidoxypropyl trimethoxysilane (GPTMS) as coupling agent, for tissue engineering applications. Aerogels were obtained using the sol-gel process followed by CO₂ supercritical drying, resulting in samples with bulk densities ranging from 0.17 g/cm³ to 0.38 g/cm³. The textural analysis by N₂-physisorption revealed an interconnected mesopore network with decreasing specific surface areas (1230–700 m²/g) and pore sizes (11.1–8.7 nm) by increasing GPTMS content (2–4 molar ratio GPTMS:CS monomer). In addition, samples exhibited extremely fast swelling by spontaneous capillary imbibition in PBS solution, presenting swelling capacities from 1.75 to 3.75. The formation of a covalent crosslinked hybrid structure was suggested by FTIR and confirmed by an increase of four hundred fold or more in the compressive strength up to 96 MPa. Instead, samples synthesized without GPTMS fractured at only 0.10–0.26 MPa, revealing a week structure consisted in interpenetrated polymer networks. The aerogels presented bioactivity in simulated body fluid (SBF), as confirmed by the in vitro formation of hydroxyapatite (HAp) layer with crystal size of approximately 2 µm size in diameter. In vitro studies revealed also non cytotoxic effect on HOB^® osteoblasts and also a mechanosensitive response. Additionally, control cells grown on glass developed scarce or no stress fibers, while cells grown on hybrid samples showed a significant (p < 0.05) increase in well-developed stress fibers and mature focal adhesion complexes. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

11 pages, 3770 KiB

Open AccessArticle

Characterization of Porous Structures of Cellulose Nanofibrils Loaded with Salicylic Acid

by Birgitte Hjelmeland McDonagh and Gary Chinga-Carrasco

Polymers 2020, 12(11), 2538; https://doi.org/10.3390/polym12112538 - 30 Oct 2020

Cited by 9 | Viewed by 2545

Abstract

Bleached and unbleached pulp fibers were treated with 2,2,6,6-tetramethylpyperidine-1-oxyl (TEMPO) mediated oxidation to obtain cellulose nanofibrils (CNFs). The resulting bleached and unbleached CNFs were mixed with salicylic acid (0, 5, 10, 20 wt%) before casting and freeze-drying or 3D-printing. A series of methods were tested and implemented to characterize the CNF materials and the porous structures loaded with salicylic acid. The CNFs were characterized with atomic force microscopy and laser profilometry, and release of salicylic acid was quantified with UV-visible absorbance spectroscopy, conductivity measurements, and inductive coupled plasma mass spectrometry (ICP-MS). Fourier-transform infrared spectroscopy (FTIR) complemented the analyses. Herein, we show that aerogels of bleached CNFs yield a greater release of salicylic acid, compared to CNF obtained from unbleached pulp. The results suggest that biodegradable constructs of CNFs can be loaded with a plant hormone that is released slowly over time, which may find uses in small scale agricultural applications and for the private home market. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

17 pages, 3166 KiB

Open AccessArticle

Preparation of Hybrid Alginate-Chitosan Aerogel as Potential Carriers for Pulmonary Drug Delivery

by Mohammad Alnaief, Rana M. Obaidat and Mo’tasem M. Alsmadi

Polymers 2020, 12(10), 2223; https://doi.org/10.3390/polym12102223 - 27 Sep 2020

Cited by 35 | Viewed by 4088

Abstract

This study aims to prepare hybrid chitosan-alginate aerogel microparticles without using additional ionic crosslinker as a possible pulmonary drug delivery system. The microparticles were prepared using the emulsion gelation method. The effect of the mixing order of the biopolymer within the emulsion and the surfactant used on final particle properties were investigated. Physicochemical characterizations were performed to evaluate particle size, density, morphology, surface area, surface charge, and the crystallinity of the preparation. The developed preparation was evaluated for its acute toxicity in adult male Sprague-Dawley rats. Measurements of zeta potential suggest that the surface charge depends mainly on the surfactant type while the order of biopolymer mixing has less impact on the surface charge. Chitosan amphiphilic properties changed the hydrophilic-lipophilic balance (HLB) of the emulsifying agents. The specific surface area of the prepared microparticles was in the range of (29.36–86.20) m²/g with a mesoporous pore size of (12.48–13.38) nm and pore volume of (0.09–0.29) cm³/g. The calculated aerodynamic diameter of the prepared particles was in the range of (0.17–2.29 µm). Toxicity studies showed that alginate-chitosan carrier developed herein caused mild lung inflammation with some renal and hepatic toxicities. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

12 pages, 3065 KiB

Open AccessArticle

Chitosan-Based Aerogel Particles as Highly Effective Local Hemostatic Agents. Production Process and In Vivo Evaluations

by Daria Lovskaya, Natalia Menshutina, Maria Mochalova, Artem Nosov and Alexander Grebenyuk

Polymers 2020, 12(9), 2055; https://doi.org/10.3390/polym12092055 - 10 Sep 2020

Cited by 35 | Viewed by 5200

Abstract

Chitosan aerogels with potential applications as effective local hemostatic agents were prepared using supercritical carbon dioxide drying to preserve the chitosan network structure featuring high internal surfaces and porosities of up to 300 m²/g and 98%, respectively. For the first time, hemostatic efficacy of chitosan-based aerogel particles was studied in vivo on a model of damage of a large vessel in the deep wound. Pigs were used as test animals. It was shown that primary hemostasis was achieved, there were no signs of rebleeding and aerogel particles were tightly fixed to the walls of the wound canal. A dense clot was formed inside the wound (at the femoral artery), which indicates stable hemostasis. This study demonstrated that chitosan-based aerogel particles have a high sorption capacity and are highly effective as local hemostatic agents which can be used to stop massive bleeding. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

13 pages, 2578 KiB

Open AccessArticle

Experimental Investigation and CFD Modeling of Supercritical Adsorption Process

by Artem Lebedev, Daria Lovskaya and Natalia Menshutina

Polymers 2020, 12(9), 1957; https://doi.org/10.3390/polym12091957 - 29 Aug 2020

Cited by 1 | Viewed by 2196

Abstract

The kinetics of the supercritical adsorption process was experimentally studied by the example of ”ibuprofen-silica aerogel” composition obtainment at various parameters: Pressure 120–200 bar and temperature 40–60 °C. Computational Fluid Dynamics (CFD) model of the supercritical adsorption process in a high-pressure apparatus based on the provisions of continuum mechanics is proposed. Using supercritical adsorption process kinetics experimental data, the dependences of the effective diffusion coefficient of active substance in the aerogel, and the maximum amount of the adsorbed active substance into the aerogel on temperature and pressure are revealed. Adequacy of the proposed model is confirmed. The proposed mathematical model allows predicting the behavior of system (fields of velocity, temperature, pressure, composition, density, etc.) at each point of the studied medium. It makes possible to predict mass transport rate of the active substance inside the porous body depending on the geometry of the apparatus, structure of flow, temperature, and pressure. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

12 pages, 1501 KiB

Open AccessArticle

Ferrocene Introduced into 5-Methylresorcinol-Based Organic Aerogels

by Ludmila V. Erkhova, Igor A. Presniakov, Michail I. Afanasov, Dmitry A. Lemenovskiy, Haojie Yu, Li Wang, Mati Danilson and Mihkel Koel

Polymers 2020, 12(7), 1582; https://doi.org/10.3390/polym12071582 - 16 Jul 2020

Cited by 5 | Viewed by 2211

Abstract

The polycondensation sol–gel reaction of 5-methylresocinol and formaldehyde with additional compounds in reaction media is a relatively simple way to produce modified aerogels. In order to obtain aerogels with a large surface area and high porosity, the conditions for gel formation, the solvent exchange process before drying, and the supercritical drying process were optimized. A successful attempt was made to introduce ferrocene units into 5-methylresocinol-formaldehyde-based aerogels. The resulting aerogels are amorphous substrates, and no aggregated ferrocene units were found in their structures. All of the aerogel samples that were obtained are structurally similar despite differences in the original ferrocene units and their initial concentration. It was found that the inclusion limit of ferrocene structural blocks into an aerogel is ~6% wt. The structures of the inclusions in which all of the Fe atoms in the aerogel substrates were present in ferrocene/ferrocenium at an approximate ratio of 60/40 to 55/45 were confirmed by X-ray photoelectron spectroscopy and Mössbauer spectroscopy. Aerogels with ferrocene/ferrocenium inclusions are likely to exhibit reversible redox activity in reactions with gaseous reagents. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

16 pages, 4047 KiB

Open AccessArticle

Optimization of Polyamide Pulp-Reinforced Silica Aerogel Composites for Thermal Protection Systems

by Mariana E. Ghica, Cláudio M.R. Almeida, Mariana Fonseca, António Portugal and Luísa Durães

Polymers 2020, 12(6), 1278; https://doi.org/10.3390/polym12061278 - 03 Jun 2020

Cited by 18 | Viewed by 3491

Abstract

The present work describes for the first time the preparation of silica-based aerogel composites containing tetraethoxysilane (TEOS) and vinyltrimethoxysilane (VTMS) reinforced with Kevlar^® pulp. The developed system was extensively investigated, regarding its physical, morphological, thermal and mechanical features. The obtained bulk density values were satisfactory, down to 208 kg·m⁻³, and very good thermal properties were achieved—namely a thermal conductivity as low as 26 mW·m⁻¹·K⁻¹ (Hot Disk^®) and thermal stability up to 550 °C. The introduction of VTMS offers a better dispersion of the polyamide fibers, as well as a higher hydrophobicity and thermal stability of the composites. The aerogels were also able to withstand five compression-decompression cycles without significant change of their size or microstructure. A design of experiment (DOE) was performed to assess the influence of different synthesis parameters, including silica co-precursors ratio, pulp amount and the solvent/Si molar ratio on the nanocomposite properties. The data obtained from the DOE allowed us to understand the significance of each parameter, offering reliable guidelines for the adjustment of the experimental procedure in order to achieve the optimum properties of the studied aerogel composites. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

16 pages, 4935 KiB

Open AccessArticle

Large, Rapid Swelling of High-cis Polydicyclopentadiene Aerogels Suitable for Solvent-Responsive Actuators

by Despoina Chriti, Grigorios Raptopoulos, Benjamin Brandenburg and Patrina Paraskevopoulou

Polymers 2020, 12(5), 1033; https://doi.org/10.3390/polym12051033 - 02 May 2020

Cited by 5 | Viewed by 3332

Abstract

High-cis polydicyclopentadiene (PDCPD) aerogels were synthesized using ring opening metathesis polymerization (ROMP) of dicyclopentadiene (DCPD) with a relatively air-stable ditungsten catalytic system, Na[W₂(μ-Cl)₃Cl₄(THF)₂]·(THF)₃ (W₂; (W³W)⁶⁺, a′²e′⁴), and norbornadiene (NBD)as a co-initiator. These aerogels are compared in terms of chemical structure and material properties with literature PDCPD aerogels obtained using well-established Ru-based alkylidenes as catalysts. The use of NBD as a co-initiator enhances the degree of crosslinking versus the more frequently used phenylacetylene (PA), yielding materials with a controlled molecular structure that would persist solvent swelling. Indeed, those PDCPD aerogels absorb selected organic solvents (e.g., chloroform, tetrahydrofuran) and swell rapidly, in some cases up to 4 times their original volume within 10 min, thus showing their potential for applications in chemical sensors and solvent-responsive actuators. The advantage of aerogels versus xerogels or dense polymers for these applications is their open porosity, which provides rapid access of the solvent to their interior, thus decreasing the diffusion distance inside the polymer itself, which in turn accelerates the response to the solvents of interest. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

13 pages, 1831 KiB

Open AccessArticle

Jet Cutting Technique for the Production of Chitosan Aerogel Microparticles Loaded with Vancomycin

by Clara López-Iglesias, Joana Barros, Inés Ardao, Pavel Gurikov, Fernando J. Monteiro, Irina Smirnova, Carmen Alvarez-Lorenzo and Carlos A. García-González

Polymers 2020, 12(2), 273; https://doi.org/10.3390/polym12020273 - 29 Jan 2020

Cited by 42 | Viewed by 4602

Abstract

Biopolymer-based aerogels can be obtained by supercritical drying of wet gels and endowed with outstanding properties for biomedical applications. Namely, polysaccharide-based aerogels in the form of microparticles are of special interest for wound treatment and can also be loaded with bioactive agents to improve the healing process. However, the production of the precursor gel may be limited by the viscosity of the polysaccharide initial solution. The jet cutting technique is regarded as a suitable processing technique to overcome this problem. In this work, the technological combination of jet cutting and supercritical drying of gels was assessed to produce chitosan aerogel microparticles loaded with vancomycin HCl (antimicrobial agent) for wound healing purposes. The resulting aerogel formulation was evaluated in terms of morphology, textural properties, drug loading, and release profile. Aerogels were also tested for wound application in terms of exudate sorption capacity, antimicrobial activity, hemocompatibility, and cytocompatibility. Overall, the microparticles had excellent textural properties, absorbed high amounts of exudate, and controlled the release of vancomycin HCl, providing sustained antimicrobial activity. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

Review

Jump to: Research

63 pages, 13793 KiB

Open AccessReview

Biorefinery Approach for Aerogels

by Tatiana Budtova, Daniel Antonio Aguilera, Sergejs Beluns, Linn Berglund, Coraline Chartier, Eduardo Espinosa, Sergejs Gaidukovs, Agnieszka Klimek-Kopyra, Angelika Kmita, Dorota Lachowicz, Falk Liebner, Oskars Platnieks, Alejandro Rodríguez, Lizeth Katherine Tinoco Navarro, Fangxin Zou and Sytze J. Buwalda

Polymers 2020, 12(12), 2779; https://doi.org/10.3390/polym12122779 - 24 Nov 2020

Cited by 34 | Viewed by 6650

Abstract

According to the International Energy Agency, biorefinery is “the sustainable processing of biomass into a spectrum of marketable bio-based products (chemicals, materials) and bioenergy (fuels, power, heat)”. In this review, we survey how the biorefinery approach can be applied to highly porous and nanostructured materials, namely aerogels. Historically, aerogels were first developed using inorganic matter. Subsequently, synthetic polymers were also employed. At the beginning of the 21st century, new aerogels were created based on biomass. Which sources of biomass can be used to make aerogels and how? This review answers these questions, paying special attention to bio-aerogels’ environmental and biomedical applications. The article is a result of fruitful exchanges in the frame of the European project COST Action “CA 18125 AERoGELS: Advanced Engineering and Research of aeroGels for Environment and Life Sciences”. Full article

(This article belongs to the Special Issue Processing, Characterization and Uses of Aerogels for Biomedical and Environmental Applications)

► Show Figures