Polymer Library

Wound Healing and Biomedicine - June 2015

This month we are focussing on wound dressing, wound healing and biomedicine.

The Polymer Library does not just hold research and information on the ‘traditional’ rubber and plastics. The extensive database also contains research and articles on many diverse polymeric topics, including this month’s focus - wound dressing, wound healing and biomedicine.

A fast growing field in polymers is biomedicine and wound care and treatment. As a dressing is in direct contact with a wound, it not only protects the injury, it can also aid recovery. Electrospinning of biopolymers is one of the most simple and effective ways of producing the type of active compounds needed to fulfil the extraordinary requirements of dressing material. Natural and synthetic materials or composites, among others, have featured heavily in the development of these biomaterials. Nano fibrous membranes, biocompatible and biodegradable polymer scaffolds and Nano particulate systems are used in wound healing and tissue engineering and are also considered as alternatives for tissue reconstruction and regeneration.

The Polymer Library scrutinises more than 1200 journals for relevant information, and unlike some freely available databases, proactively searches for new journals from the major publishers as well as via the Directory of Open Access Journals. The time taken to create a comprehensive yet specialist collection of indexed bibliographic records will save you precious time, helping you to find the information you need, faster.

Here’s a few sample records for some of the latest developments in this area.

Abstracts

These abstracts were highlighted in the June Newsletter and found in the Polymer Library.

Click on the 7-digit accession numbers to find out about ordering a copyright-cleared full text copy of the items shown.

1191448 - Investigation into the potential use of poly(vinyl alcohol)/methylglyoxal fibres as antibacterial wound dressing components
As problems of antibiotic resistance increase, a continuing need for effective bioactive wound dressings is anticipated for the treatment of infected chronic wounds. Naturally derived antibacterial agents, such as Manuka honey, consist of a mixture of compounds, more than one of which can influence antimicrobial potency. The non-peroxide bacteriostatic properties of Manuka honey have been previously linked to the presence of methylglyoxal. The incorporation of methylglyoxal as a functional antibacterial additive during fibre production was explored as a potential route for manufacturing wound dressing components. Synthetic methylglyoxal and poly(vinyl alcohol) were fabricated into webs of sub-micron fibres by means of electrostatic spinning of an aqueous spinning solution. Composite fabrics were also produced by direct deposition of the poly(vinyl alcohol)-methylglyoxal fibres onto a preformed spunbonded nonwoven substrate. Attenuated total reflectance fourier transform infrared and proton nuclear magnetic resonance spectroscopies confirmed the presence of methylglyoxal within the resulting fibre structure. The antibacterial activity of the fibres was studied using strains of Staphylococcus aureus and Escherichia coli. Strong antibacterial activity, as well as diffusion of methylglyoxal from the fibres was observed at a concentration of 1.55 mg/cm. (49 ref)
Journal of Biomaterials Applications, 29, No.8, 2015, p.1193-1200, ISSN: 0885-3282, DOI: 10.1177/0885328214556159
Bulman S E; Goswami P; Tronci G; Russell S J; Carr C

1189803 - Properties and medical applications of polylactic acid: a review (OPEN ACCESS - FREE ACCESS TO FULL TEXT)
Polylactic acid (PLA), one of the well-known biodegradable polyesters, has been studied extensively for tissue engineering and drug delivery systems, and it was also used widely in human medicine. A new method to synthesize PLA (ring-opening polymerisation), which allowed the economical production of a high molecular weight PLA polymer, broadened its applications, and this processing would be a potential substitute for petroleum-based products. This review described the principles of the polymerisation reactions of PLA and, then, outlined the various materials properties affecting the performance of PLA polymer, such as rheological, mechanical, thermal, and barrier properties as well as the processing technologies which were used to fabricate products based on PLA. In addition, the biodegradation processes of products which were shaped from PLA were discussed and reviewed. The potential applications of PLA in the medical fields, such as tissue engineering, wound management, drugs delivery, and orthopaedic devices, were also highlighted. 99 Refs.
Express Polymer Letters, 9, No.5, 2015, p.435-455, ISSN: 1788-618X, DOI: 10.3144/expresspolymlett.2015.42
Hamad K; Kaseem M; Yang H W; Deri F; Ko Y G

1195944 - Preparation and characterization of polyhydroxybutyrate-co-hydroxyvalerate/silk fibroin nanofibrous scaffolds for skin tissue engineering
Nanofibrous scaffolds were obtained by co-electrospinning poly (3-hydroxybuty-rate-co-3-hydroxyvalerate) (PHBV) and fibroin regenerated from silk in different proportions using 1,1,1,3,3,3-hexafluoro-2-isopropanol (HFIP) as solvent. Field emission scanning electron microscope (FESEM) investigation showed that the fibre diameters of the nanofibrous scaffolds ranged from 190 to 460 nm. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy analysis (FT-IR) showed that the main structure of silk fibroin (SF) in the nanofibrous scaffold was (beta)-sheet. Compared to the PHBV nanofibrous scaffold, the surface hydrophilicity and water-uptake capability of the PHBV/SF nanofibrous scaffold with 50/50 were improved. The results of cell adhesion experiment showed that the fibroblasts adhered more to the PHBV/SF nanofibrous scaffold with 50/50 than the pure PHBV nanofibrous scaffold. The proliferation of fibroblast on the PHBV/SF nanofibrous scaffold with 50/50 was higher than that on the pure PHBV nanofibrous scaffold. Our results indicated that the PHBV/SF nanofibrous scaffold with 50/50 may be a better candidate for biomedical applications such as skin tissue engineering and wound dressing. (47 ref)
Polymer Engineering and Science, 55, No.4, 2015, p.907-916, ISSN: 0032-3888, DOI: 10.1002/pen.23958
Caihong Lei; Hailin Zhu; Jingjing Li; Jiuming Li; Xinxing Feng; Jianyong Chen

1196156 - Electrospun polystyrene fiber diameter influencing bacterial attachment, proliferation, and growth
Electrospun materials have been widely investigated in the past few decades as candidates for tissue engineering applications. However, there is little available data on the mechanisms of interaction of bacteria with electrospun wound dressings of different morphology and surface chemistry. This knowledge could allow the development of effective devices against bacterial infections in chronic wounds. In this paper, the interactions of three bacterial species (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus) with electrospun polystyrene meshes were investigated. Bacterial response to meshes with different fibre diameters was assessed through a combination of scanning electron microscopy (SEM) and confocal microscopy. Experiments included attachment studies in liquid medium but also directly onto agar plates; the latter was aimed at mimicking a chronic wound environment. Fibre diameter was shown to affect the ability of bacteria to proliferate within the fibrous networks, depending on cell size and shape. The highest proliferation rates occurred when fibre diameter was close to the bacterial size. Nanofibres were found to induce conformational changes of rod shaped bacteria, limiting the colonization process and inducing cell death. The data suggest that simply tuning the morphological properties of electrospun fibres may be one strategy used to control biofilm formation within wound dressings.
ACS Applied Materials and Interfaces, 7, No.14, 15 Apr. 2015, p.7644-7652, ISSN: 1944-8244, DOI: 10.1021/acsami.5b00453
Abrigo M; Kingshott P; McArthur S L

1197407 - Composite chitosan/poly(ethylene oxide) electrospun nanofibrous mats as novel wound dressing matrixes for the controlled release of drugs
The aim of this study was to develop novel biomedical electrospun nanofibre mats for controlled drug release, in particular to release a drug directly to an injury site to accelerate wound healing. Here, nanofibres of chitosan (CS), poly(ethylene oxide) (PEO), and a 90 : 10 composite blend, loaded with a fluoroquinolone antibiotic, such as ciprofloxacin hydrochloride (CipHCl) or moxifloxacin hydrochloride (Moxi), were successfully prepared by an electrospinning technique. The morphology of the electrospun nanofibres was investigated by scanning electron microscopy. The functional groups of the electrospun nanofibres before and after crosslinking were characterised by Fourier transform infrared spectroscopy. X-ray diffraction results indicated an amorphous distribution of the drug inside the nanofibre blend. In vitro drug-release evaluations showed that the crosslinking could control the rate and period of drug release in wound-healing applications. The inhibition of bacterial growth for both Escherichia coli and Staphylococcus aureus were achieved on the CipHCl- and Moxi-loaded nanofibres. In addition, both types of CS/PEO and drug-containing CS/PEO nanofibres showed excellent cytocompatibility in the cytotoxicity assays. (43 ref)
Journal of Applied Polymer Science, 132, No.24, 2015, paper 42060, pp.8, ISSN: 0021-8995, DOI: 10.1002/app.42060
Feng Cheng; Jing Gao; Lu Wang; Xingyou Hu

1197000 - Electroactive tissue scaffolds with aligned pores as instructive platforms for biomimetic tissue engineering (OPEN ACCESS - FREE ACCESS TO FULL TEXT)
Tissues in the body are hierarchically structured composite materials with tissue-specific chemical and topographical properties. Here we report the preparation of tissue scaffolds with macroscopic pores generated via the dissolution of a sacrificial supramolecular polymer-based crystal template (urea) from a biodegradable polymer-based scaffold (polycaprolactone, PCL). Furthermore, we report a method of aligning the supramolecular polymer-based crystals within the PCL, and that the dissolution of the sacrificial urea yields scaffolds with macroscopic pores that are aligned over long, clinically-relevant distances (i.e., centimetre scale). The pores act as topographical cues to which rat Schwann cells respond by aligning with the long axis of the pores. Generation of an interpenetrating network of polypyrrole (PPy) and poly(styrene sulphonate) (PSS) in the scaffolds yields electroactive tissue scaffolds that allow the electrical stimulation of Schwann cells cultured on the scaffolds which increases the production of nerve growth factor (NGF). 98 Refs.
Bioengineering, 2, No.1, Mar. 2015, p.15-34, ISSN: 2306-5354, DOI: 10.3390/bioengineering2010015
Hardy J G; Cornelison R C; Sukhavasi R C; Saballos R J; Vu P; Kaplan D L; Schmidt C E

1197080 - Preparation and initial biocompatability evaluation of biogenic hydroxyapatite/chitosan/polyvinyl alcohol biocomposite as a drug delivery carrier of proneurogenic factor (OPEN ACCESS - FREE ACCESS TO FULL TEXT)
This study explores the synthesis of biogenic hydroxyapatite (HAp)/chitosan (CS)/polyvinyl alcohol (PVA) bio-composites for delivery of proneurogenic factor, retinoic acid for reconstruction of craniofacial deformities. In order to accomplish this aim, we started with the synthesis of HAp using the biomolecules occluded in the cucumber peel (CPHAp). Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction studies (XRD) studies confirmed the purity and morphology of CPHAp. Further, a microenvironment for nerve cell growth was designed by synthesis of biogenic HAp/CS/PVA blends loaded with retinoic acid (CS-PVA-CPHAp-all-trans-retinoic acid [ATRA]). The prepared biocomposites were characterised under advanced analytical instruments such as SEM, FTIR, and XRD. The SEM analysis for the prepared biocomposites confirmed the formation of interconnected porous matrix. The results of FTIR confirm the biocomposite formation without chemical modification of ATRA. From XRD the amorphous nature was confirmed, inducing suitability of the material for delivery process. Release of ATRA from CS-PVA-CPHAp-ATRA was sustained, with a cumulative release of 55% at the end of 10th day. Furthermore, 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay indicated that, the biocomposites are better in scaffold properties, and it provides a healthier environment for cell attachment and spreading. The porous CS-PVA CPHAp-ATRA composites may be applied to craniofacial tissue engineering as a long-term or permanent scaffold due to their good biocompatibility and sustained release of proneurogenic factor. 20 Refs.
Asian Journal of Pharmaceutical and Clinical Research, 8, No.1, Jan.-Feb. 2015, p.345-350, ISSN: 0974-2441
Nellore J; Vijayalakshmi S; Priyanka P; Priyadarshini S

DON'T FORGET!

If you think that access to the Polymer Library might be of use to you, you can get in touch to find out more.

The Electrospinning and Nanofibres Polymer Bulletin is available with 20% off until 17 August 2015.

Not quite what you are looking for? Why not consider our Antimicrobials and Biocides Bulletin. You could also try Medical Devices Bulletin or Pharmaceutical Applications all with 20% off until 17 August 2015



ALSO FROM SMITHERS RAPRA

Advances in Wound Healing Materials

Available with 10% off until 31 July 2015

Wound healing and wound care technologies are an ever expanding field with the advancement of materials science, biomedicine and tissue engineering. In the year 2011 the global wound care market generated US$ 6,500 million with an annual growth rate of 7.5%. The global advanced wound care products market share in 2023 is predicted to be approximately US$ 16,300 million. Find out more...

Electrospinning for Advanced Biomedical Applications and Therapies

The main focus of this book is on the development of electrospun membranes for advanced biomedical technologies including tissue engineering and drug delivery devices. Serving as a reference book for the beginner this book also provides an in-depth analysis of the challenges to be overcome in the future. Each section of the book covers not only the developments in the various fields of application of the electrospun meshes, but also the advances required for the successful development of new and high-end biomedical applications. Find out more...

Update on Chitosan: A Non-Viral Gene Delivery Vector

Also available with 10% off

Among the various natural polymer-based gene delivery vectors, chitosan is the most prominent. As a biocompatible, biodegradable, nontoxic and easily modifiable material, chitosan has been widely researched for a variety of biomedical applications such as wound healing, drug/gene delivery systems, implant coatings and tissue engineering/regeneration. Find out more...

%>