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A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Biomaterials".

Deadline for manuscript submissions: closed (20 July 2022) | Viewed by 31958

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Prof. Roser Sabater i Serra

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Centre for Biomaterials and Tissue Engineering, Universitat Politècnica de València, Valencia, Spain
Interests: polymers; biomaterials; composites and nanocomposites; electroactive polymers; tissue engineering; regenerative medicine; biomedical engineering and computer simulation of polymers

Prof. Dr. Ángel Serrano-Aroca

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Biomaterials and Bioengineering Lab, Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia San Vicente Mártir, c/Guillem de Castro 94, 46001 Valencia, Spain
Interests: polymers; nanomaterials; nanocomposites; biomaterials; antimicrobial materials; regenerative medicine; tissue engineering; biomedical engineering
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Special Issue Information

Dear Colleagues,

Polymers in the form of films, fibers, nano- and microspheres, composites, and porous supports shareow promising biomaterials for a wide range of advanced biomedical applications: wound healing, controlling drug/gene delivery, anti-cancer therapy, biosensors, stem cell therapy, and tissue engineering. Tissue engineering (TE) combines cells, porous materials (scaffolds), and suitable bioactive factors to regenerate biological tissues and, ultimately, whole organs. The application of polymers in all these fields are often hindered by their lack of specific properties. In this regard, polymer-based materials in the form of hydrogels, interpenetrated polymer networks, composites, or nanocomposites in pure form, functionalized, or in combination with other materials, nanomaterials, particles, or nanoparticles can be exploited to produce a broad range of advanced nano- and macro-biomaterials. Specific features, such as mechanical performance, wettability, water diffusion, electroactivity, thermal properties, and even antimicrobial activity, can be tailored to engineer biomimetic microenvironments able to promote cellular interactions and tissue development for tissue engineering and regenerative medicine applications.

In this context, we invite authors to submit original research articles, communications and reviews for this Special Issue of Materials MDPI, “Polymer-Based Biomaterials and Tissue Engineering”, which focuses on all the advances in this research field.

Prof. Roser Sabater i Serra
Prof. Ángel Serrano-Aroca
Guest Editors

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Keywords

Polymers as biomaterials (biodegradable or biostable, natural or synthetic)
Polymeric scaffolds for tissue engineering (TE)
Polymer-based composites and nanocomposites
Hydrogels, interpenetrated polymer networks, plasma polymers
Bioactive and antimicrobial polymers
Surface modification and functionalization of polymers for TE (layer-by-layer assembly, stimuli-responsive polymers, etc.)
Nanobiomaterials (nanoparticles and nanofibers, carbon nanomaterials)
In vitro and in vivo assessment of polymer-based biomaterials (interface biomaterial–cell, biomimetic microenvironments, cell stimulation, stem cell differentiation)
Controlled drug/gene delivery based on polymers
Polymers for biomedical engineering, nanobiotechnology, and nanomedicine

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Published Papers (11 papers)

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Editorial

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3 pages, 196 KiB

Open AccessEditorial

Special Issue: “Polymer-Based Biomaterials and Tissue Engineering”

by Roser Sabater i Serra and Ángel Serrano-Aroca

Materials 2023, 16(14), 4923; https://doi.org/10.3390/ma16144923 - 10 Jul 2023

Cited by 1 | Viewed by 1372

Abstract

Polymers in the form of films, fibers, nano- and microspheres, composites, and porous supports are promising biomaterials for a wide range of advanced biomedical applications: wound healing, controlling drug delivery, anti-cancer therapy, biosensors, stem cell therapy, and tissue engineering [...] Full article

(This article belongs to the Special Issue Polymer-Based Biomaterials and Tissue Engineering)

Research

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17 pages, 4085 KiB

Open AccessArticle

Engineered Highly Porous Polyvinyl Alcohol Hydrogels with Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and Graphene Nanosheets for Musculoskeletal Tissue Engineering: Morphology, Water Sorption, Thermal, Mechanical, Electrical Properties, and Biocompatibility

by José Luis Aparicio-Collado, Qiqi Zheng, José Molina-Mateo, Constantino Torregrosa Cabanilles, Ana Vidaurre, Ángel Serrano-Aroca and Roser Sabater i Serra

Materials 2023, 16(8), 3114; https://doi.org/10.3390/ma16083114 - 15 Apr 2023

Cited by 3 | Viewed by 1751

Abstract

Electroactive composite materials are very promising for musculoskeletal tissue engineering because they can be applied in combination with electrostimulation. In this context, novel graphene-based poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/polyvinyl alcohol (PHBV/PVA) semi-interpenetrated networks (semi-IPN) hydrogels were engineered with low amounts of graphene (G) nanosheets dispersed within the polymer matrix to endow them with electroactive properties. The nanohybrid hydrogels, obtained by applying a hybrid solvent casting–freeze-drying method, show an interconnected porous structure and a high water-absorption capacity (swelling degree > 1200%). The thermal characterization indicates that the structure presents microphase separation, with PHBV microdomains located between the PVA network. The PHBV chains located in the microdomains are able to crystallize; even more after the addition of G nanosheets, which act as a nucleating agent. Thermogravimetric analysis indicates that the degradation profile of the semi-IPN is located between those of the neat components, with an improved thermal stability at high temperatures (>450 °C) after the addition of G nanosheets. The mechanical (complex modulus) and electrical properties (surface conductivity) significantly increase in the nanohybrid hydrogels with 0.2% of G nanosheets. Nevertheless, when the amount of G nanoparticles increases fourfold (0.8%), the mechanical properties diminish and the electrical conductivity does not increase proportionally, suggesting the presence of G aggregates. The biological assessment (C2C12 murine myoblasts) indicates a good biocompatibility and proliferative behavior. These results reveal a new conductive and biocompatible semi-IPN with remarkable values of electrical conductivity and ability to induce myoblast proliferation, indicating its great potential for musculoskeletal tissue engineering. Full article

(This article belongs to the Special Issue Polymer-Based Biomaterials and Tissue Engineering)

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15 pages, 3069 KiB

Open AccessArticle

Temperature-Responsive Polysaccharide Microparticles Containing Nanoparticles: Release of Multiple Cationic/Anionic Compounds

by Takumi Sato and Yoshihiko Murakami

Materials 2022, 15(13), 4717; https://doi.org/10.3390/ma15134717 - 5 Jul 2022

Cited by 3 | Viewed by 1796

Abstract

Most drug carriers used in pulmonary administration are microparticles with diameters over 1 µm. Only a few examples involving nanoparticles have been reported because such small particles are readily exhaled. Consequently, the development of microparticles capable of encapsulating nanoparticles and a wide range of compounds for pulmonary drug-delivery applications is an important objective. In this study, we investigated the development of polysaccharide microparticles containing nanoparticles for the temperature-responsive and two-step release of inclusions. The prepared microparticles containing nanoparticles can release two differently charged compounds in a stepwise manner. The particles have two different drug release pathways: one is the release of nanoparticle inclusions from the nanoparticles and the other is the release of microparticle inclusions during microparticle collapse. The nanoparticles can be efficiently delivered deep into the lungs and a wide range of compounds are released in a charge-independent manner, owing to the suitable roughness of the microparticle surface. These polysaccharide microparticles containing nanoparticles are expected to be used as temperature-responsive drug carriers, not only for pulmonary administration but also for various administration routes, including transpulmonary, intramuscular, and transdermal routes, that can release multiple drugs in a controlled manner. Full article

(This article belongs to the Special Issue Polymer-Based Biomaterials and Tissue Engineering)

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21 pages, 6829 KiB

Open AccessArticle

Accelerated Endothelialization of Nanofibrous Scaffolds for Biomimetic Cardiovascular Implants

by Claudia Matschegewski, Stefanie Kohse, Jana Markhoff, Michael Teske, Katharina Wulf, Niels Grabow, Klaus-Peter Schmitz and Sabine Illner

Materials 2022, 15(6), 2014; https://doi.org/10.3390/ma15062014 - 9 Mar 2022

Cited by 14 | Viewed by 2798

Abstract

Nanofiber nonwovens are highly promising to serve as biomimetic scaffolds for pioneering cardiac implants such as drug-eluting stent systems or heart valve prosthetics. For successful implant integration, rapid and homogeneous endothelialization is of utmost importance as it forms a hemocompatible surface. This study aims at physicochemical and biological evaluation of various electrospun polymer scaffolds, made of FDA approved medical-grade plastics. Human endothelial cells (EA.hy926) were examined for cell attachment, morphology, viability, as well as actin and PECAM 1 expression. The appraisal of the untreated poly-L-lactide (PLLA L210), poly-ε-caprolactone (PCL) and polyamide-6 (PA-6) nonwovens shows that the hydrophilicity (water contact angle > 80°) and surface free energy (<60 mN/m) is mostly insufficient for rapid cell colonization. Therefore, modification of the surface tension of nonpolar polymer scaffolds by plasma energy was initiated, leading to more than 60% increased wettability and improved colonization. Additionally, NH₃-plasma surface functionalization resulted in a more physiological localization of cell–cell contact markers, promoting endothelialization on all polymeric surfaces, while fiber diameter remained unaltered. Our data indicates that hydrophobic nonwovens are often insufficient to mimic the native extracellular matrix but also that they can be easily adapted by targeted post-processing steps such as plasma treatment. The results achieved increase the understanding of cell–implant interactions of nanostructured polymer-based biomaterial surfaces in blood contact while also advocating for plasma technology to increase the surface energy of nonpolar biostable, as well as biodegradable polymer scaffolds. Thus, we highlight the potential of plasma-activated electrospun polymer scaffolds for the development of advanced cardiac implants. Full article

(This article belongs to the Special Issue Polymer-Based Biomaterials and Tissue Engineering)

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17 pages, 2955 KiB

Open AccessArticle

Investigations on the Influence of Collagen Type on Physicochemical Properties of PVP/PVA Composites Enriched with Hydroxyapatite Developed for Biomedical Applications

by Magdalena Głąb, Anna Drabczyk, Sonia Kudłacik-Kramarczyk, Magdalena Kędzierska, Agnieszka Tomala, Agnieszka Sobczak-Kupiec, Dariusz Mierzwiński and Bożena Tyliszczak

Materials 2022, 15(1), 37; https://doi.org/10.3390/ma15010037 - 21 Dec 2021

Cited by 3 | Viewed by 2891

Abstract

Nowadays, a great attention is directed into development of innovative multifunctional composites which may support bone tissue regeneration. This may be achieved by combining collagen and hydroxyapatite showing bioactivity, osteoconductivity and osteoinductivity with such biocompatible polymers as polyvinylpyrrolidone (PVP) and poly(vinyl alcohol) (PVA). Here PVA/PVP-based composites modified with hydroxyapatite (HAp, 10 wt.%) and collagen (30 wt.%) were obtained via UV radiation while two types of collagen were used (fish and bovine) and crosslinking agents differing in the average molecular weight. Next, their chemical structure was characterized using Fourier transform infrared (FT-IR) spectroscopy, roughness of their surfaces was determined using a stylus contact profilometer while their wettability was evaluated by a sessile drop method followed by the measurements of their surface free energy. Subsequently, swelling properties of composites were verified in simulated physiological liquids as well as the behavior of composites in these liquids by pH measurements. It was proved that collagen-modified composites showed higher swelling ability (even 25% more) compared to unmodified ones, surface roughness, biocompatibility towards simulated physiological liquids and hydrophilicity (contact angles lower than 90°). Considering physicochemical properties of developed materials and a possibility of the preparation of their various shapes and sizes, it may be concluded that developed materials showed great application potential for biomedical use, e.g., as materials filling bone defects supporting their treatments and promoting bone tissue regeneration due to the presence of hydroxyapatite with osteoinductive and osteoconductive properties. Full article

(This article belongs to the Special Issue Polymer-Based Biomaterials and Tissue Engineering)

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21 pages, 4493 KiB

Open AccessArticle

Optimized Rivastigmine Nanoparticles Coated with Eudragit for Intranasal Application to Brain Delivery: Evaluation and Nasal Ciliotoxicity Studies

by Mansi Bhanderi, Jigar Shah, Bapi Gorain, Anroop B. Nair, Shery Jacob, Syed Mohammed Basheeruddin Asdaq, Santosh Fattepur, Abdulhakeem S. Alamri, Walaa F. Alsanie, Majid Alhomrani, Sreeharsha Nagaraja and Md. Khalid Anwer

Materials 2021, 14(21), 6291; https://doi.org/10.3390/ma14216291 - 22 Oct 2021

Cited by 33 | Viewed by 3938

Abstract

Rivastigmine, a reversible cholinesterase inhibitor, is frequently indicated in the management of demented conditions associated with Alzheimer disease. The major hurdle of delivering this drug through the oral route is its poor bioavailability, which prompted the development of novel delivery approaches for improved efficacy. Due to numerous beneficial properties associated with nanocarriers in the drug delivery system, rivastigmine nanoparticles were fabricated to be administer through the intranasal route. During the development of the nanoparticles, preliminary optimization of processing and formulation parameters was done by the design of an experimental approach. The drug–polymer ratio, stirrer speed, and crosslinking time were fixed as independent variables, to analyze the effect on the entrapment efficiency (% EE) and in vitro drug release of the drug. The formulation (D8) obtained from 2³ full factorial designs was further coated using Eudragit EPO to extend the release pattern of the entrapped drug. Furthermore, the 1:1 ratio of core to polymer depicted spherical particle size of ~175 nm, % EE of 64.83%, 97.59% cumulative drug release, and higher flux (40.39 ± 3.52 µg.h/cm²). Finally, the intranasal ciliotoxicity study on sheep nasal mucosa revealed that the exposure of developed nanoparticles was similar to the negative control group, while destruction of normal architecture was noticed in the positive control test group. Overall, from the in vitro results it could be summarized that the optimization of nanoparticles’ formulation of rivastigmine for intranasal application would be retained at the application site for a prolonged duration to release the entrapped drug without producing any local toxicity at the mucosal region. Full article

(This article belongs to the Special Issue Polymer-Based Biomaterials and Tissue Engineering)

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17 pages, 6480 KiB

Open AccessArticle

Improvement of Drug Release and Compatibility between Hydrophilic Drugs and Hydrophobic Nanofibrous Composites

by Hazim J. Haroosh, Yu Dong, Shaimaa Jasim and Seeram Ramakrishna

Materials 2021, 14(18), 5344; https://doi.org/10.3390/ma14185344 - 16 Sep 2021

Cited by 11 | Viewed by 2610

Abstract

Electrospinning is a flexible polymer processing method to produce nanofibres, which can be applied in the biomedical field. The current study aims to develop new electrospun hybrid nanocomposite systems to benefit the sustained release of hydrophilic drugs with hydrophobic polymers. In particular, electrospun hybrid materials consisting of polylactic acid (PLA):poly(ε-caprolactone) (PCL) blends, as well as PLA:PCL/halloysite nanotubes-3-aminopropyltriethoxysilane (HNT-ASP) nanocomposites were developed in order to achieve sustained release of hydrophilic drug tetracycline hydrochloride (TCH) using hydrophobic PLA:PCL nanocomposite membranes as a drug carrier. The impact of interaction between two commonly used drugs, namely TCH and indomethacin (IMC) and PLA:PCL blends on the drug release was examined. The drug release kinetics by fitting the experimental release data with five mathematical models for drug delivery were clearly demonstrated. The average nanofiber diameters were found to be significantly reduced when increasing the TCH concentration due to increasing solution electrical conductivity in contrast to the presence of IMC. The addition of both TCH and IMC drugs to PLA:PCL blends reduced the crystallinity level, glass transition temperature (T_g) and melting temperature (T_m) of PCL within the blends. The decrease in drug release and the impairment elimination for the interaction between polymer blends and drugs was accomplished by mobilising TCH into HNT-ASP for their embedding effect into PLA:PCL nanofibres. The typical characteristic was clearly identified with excellent agreement between our experimental data obtained and Ritger–Peppas model and Zeng model in drug release kinetics. The biodegradation behaviour of nanofibre membranes indicated the effective incorporation of TCH onto HNT-ASP. Full article

(This article belongs to the Special Issue Polymer-Based Biomaterials and Tissue Engineering)

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12 pages, 2983 KiB

Open AccessArticle

Comparison of the Influence of 45S5 and Cu-Containing 45S5 Bioactive Glass (BG) on the Biological Properties of Novel Polyhydroxyalkanoate (PHA)/BG Composites

by Katharina Schuhladen, Barbara Lukasiewicz, Pooja Basnett, Ipsita Roy and Aldo R. Boccaccini

Materials 2020, 13(11), 2607; https://doi.org/10.3390/ma13112607 - 8 Jun 2020

Cited by 10 | Viewed by 2786

Abstract

Polyhydroxyalkanoates (PHAs), due to their biodegradable and biocompatible nature and their ability to be formed in complex structures, are excellent candidates for fabricating scaffolds used in tissue engineering. By introducing inorganic compounds, such as bioactive glasses (BGs), the bioactive properties of PHAs can be further improved. In addition to their outstanding bioactivity, BGs can be additionally doped with biological ions, which in turn extend the functionality of the BG-PHA composite. Here, different PHAs were combined with 45S5 BG, which was additionally doped with copper in order to introduce antibacterial and angiogenic properties. The resulting composite was used to produce scaffolds by the salt leaching technique. By performing indirect cell biology tests using stromal cells, a dose-depending effect of the dissolution products released from the BG-PHA scaffolds could be found. In low concentrations, no toxic effect was found. Moreover, in higher concentrations, a minor reduction of cell viability combined with a major increase in VEGF release was measured. This result indicates that the fabricated composite scaffolds are suitable candidates for applications in soft and hard tissue engineering. However, more in-depth studies are necessary to fully understand the release kinetics and the resulting long-term effects of the BG-PHA composites. Full article

(This article belongs to the Special Issue Polymer-Based Biomaterials and Tissue Engineering)

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Review

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30 pages, 8478 KiB

Open AccessReview

Green Copolymers Based on Poly(Lactic Acid)—Short Review

by Konrad Stefaniak and Anna Masek

Materials 2021, 14(18), 5254; https://doi.org/10.3390/ma14185254 - 13 Sep 2021

Cited by 70 | Viewed by 6473

Abstract

Polylactic acid (PLA) is a biodegradable and biocompatible polymer that can be applied in the field of packaging and medicine. Its starting substrate is lactic acid and, on this account, PLA can also be considered an ecological material produced from renewable resources. Apart from several advantages, polylactic acid has drawbacks such as brittleness and relatively high glass transition and melting temperatures. However, copolymerization of PLA with other polymers improves PLA features, and a desirable material marked by preferable physical properties can be obtained. Presenting a detailed overview of the accounts on the PLA copolymerization accomplishments is the innovation of this paper. Scientific findings, examples of copolymers (including branched, star, grafted or block macromolecules), and its applications are discussed. As PLA copolymers can be potentially used in pharmaceutical and biomedical areas, the attention of this article is also placed on the advances present in this field of study. Moreover, the subject of PLA synthesis is described. Three methods are given: azeotropic dehydrative condensation, direct poly-condensation, and ring-opening polymerization (ROP), along with its mechanisms. The applied catalyst also has an impact on the end product and should be adequately selected depending on the intended use of the synthesized PLA. Different ways of using stannous octoate (Sn(Oct)₂) and examples of the other inorganic and organic catalysts used in PLA synthesis are presented. Full article

(This article belongs to the Special Issue Polymer-Based Biomaterials and Tissue Engineering)

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14 pages, 302 KiB

Open AccessReview

The Role of Mesh Implants in Surgical Treatment of Parastomal Hernia

by Karolina Turlakiewicz, Michał Puchalski, Izabella Krucińska and Witold Sujka

Materials 2021, 14(5), 1062; https://doi.org/10.3390/ma14051062 - 24 Feb 2021

Cited by 7 | Viewed by 2816 | Correction

Abstract

A parastomal hernia is a common complication following stoma surgery. Due to the large number of hernial relapses and other complications, such as infections, adhesion to the intestines, or the formation of adhesions, the treatment of hernias is still a surgical challenge. The current standard for the preventive and causal treatment of parastomal hernias is to perform a procedure with the use of a mesh implant. Researchers are currently focusing on the analysis of many relevant options, including the type of mesh (synthetic, composite, or biological), the available surgical techniques (Sugarbaker’s, “keyhole”, or “sandwich”), the surgical approach used (open or laparoscopic), and the implant position (onlay, sublay, or intraperitoneal onlay mesh). Current surface modification methods and combinations of different materials are actively explored areas for the creation of biocompatible mesh implants with different properties on the visceral and parietal peritoneal side. It has been shown that placing the implant in the sublay and intraperitoneal onlay mesh positions and the use of a specially developed implant with a 3D structure are associated with a lower frequency of recurrences. It has been shown that the prophylactic use of a mesh during stoma formation significantly reduces the incidence of parastomal hernias and is becoming a standard method in medical practice. Full article

(This article belongs to the Special Issue Polymer-Based Biomaterials and Tissue Engineering)

Other

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3 pages, 184 KiB

Open AccessCorrection

Correction: Turlakiewicz et al. The Role of Mesh Implants in Surgical Treatment of Parastomal Hernia. Materials 2021, 14, 1062

by Karolina Turlakiewicz, Michał Puchalski, Izabella Krucińska and Witold Sujka

Materials 2021, 14(13), 3511; https://doi.org/10.3390/ma14133511 - 24 Jun 2021

Cited by 1 | Viewed by 1381

Abstract

We have recently been made aware by [...] Full article

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