122 results on '"Biomedical polymers"'
Search Results
2. Biomedical applications of polymers in biosensors, cancer vaccines and drug delivery systems.
- Author
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Selvakumar, P.
- Subjects
- *
DRUG delivery systems , *CANCER vaccines , *MEDICAL polymers , *ANTINEOPLASTIC agents , *BIOMATERIALS , *BIOSENSORS , *PEPTIDES - Abstract
To analyze the substantial development of biomedical polymers in a number of potential biomedical domains, including the disease diagnosis and therapy. Results. The relationship between material's properties and functions for matching biomedical applications is thoroughly elucidated in this paper, along with a rundown of current advancements in the production and appliance of biomedical polymers. The peptide, biomembrane, microbe and cell-based biomedical polymers are presented and highlighted as new biomaterials for the tumor precision treatment. Additionally, the prospects and difficulties of creating the future biomedical polymers, which are healthier, safer, and more effective, are appraised. Conclusions. This systematic and in-depth analysis of the most recent advancements in the biomedical polymers development is intended to inspire and promote new discoveries in the basic science and clinical application. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
3. Recent Advances in Nanomaterials for Asthma Treatment.
- Author
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Zuo, Xu, Guo, Xiaoping, Gu, Yinuo, Zheng, Haoyu, Zhou, Zhengjie, Wang, Xinlei, Jiang, Shengyu, Wang, Guoqiang, Xu, Caina, and Wang, Fang
- Subjects
- *
DRUG delivery systems , *INHALERS , *COMBINATION drug therapy , *NANOSTRUCTURED materials , *TECHNOLOGICAL innovations , *ASTHMA , *DRUG bioavailability - Abstract
Asthma is a chronic airway inflammatory disease with complex mechanisms, and these patients often encounter difficulties in their treatment course due to the heterogeneity of the disease. Currently, clinical treatments for asthma are mainly based on glucocorticoid-based combination drug therapy; however, glucocorticoid resistance and multiple side effects, as well as the occurrence of poor drug delivery, require the development of more promising treatments. Nanotechnology is an emerging technology that has been extensively researched in the medical field. Several studies have shown that drug delivery systems could significantly improve the targeting, reduce toxicity and improve the bioavailability of drugs. The use of multiple nanoparticle delivery strategies could improve the therapeutic efficacy of drugs compared to traditional delivery methods. Herein, the authors presented the mechanisms of asthma development and current therapeutic methods. Furthermore, the design and synthesis of different types of nanomaterials and micromaterials for asthma therapy are reviewed, including polymetric nanomaterials, solid lipid nanomaterials, cell membranes-based nanomaterials, and metal nanomaterials. Finally, the challenges and future perspectives of these nanomaterials are discussed to provide guidance for further research directions and hopefully promote the clinical application of nanotherapeutics in asthma treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
4. Recent progress in nanocomposites of carbon dioxide fixation derived reproducible biomedical polymers
- Author
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Xin Liu, Zhiwen Jiang, Dejun Xing, Yan Yang, Zhiying Li, and Zhiqiang Sun
- Subjects
nanocomposites ,carbon dioxide fixation ,reproducible ,biomedical polymers ,decarbonization ,Chemistry ,QD1-999 - Abstract
In recent years, the environmental problems accompanying the extensive application of biomedical polymer materials produced from fossil fuels have attracted more and more attentions. As many biomedical polymer products are disposable, their life cycle is relatively short. Most of the used or overdue biomedical polymer products need to be burned after destruction, which increases the emission of carbon dioxide (CO2). Developing biomedical products based on CO2 fixation derived polymers with reproducible sources, and gradually replacing their unsustainable fossil-based counterparts, will promote the recycling of CO2 in this field and do good to control the greenhouse effect. Unfortunately, most of the existing polymer materials from renewable raw materials have some property shortages, which make them unable to meet the gradually improved quality and property requirements of biomedical products. In order to overcome these shortages, much time and effort has been dedicated to applying nanotechnology in this field. The present paper reviews recent advances in nanocomposites of CO2 fixation derived reproducible polymers for biomedical applications, and several promising strategies for further research directions in this field are highlighted.
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- 2022
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5. SYNTHETIC POLYMERS AND THEIR USE IN CLINICAL MEDICINE: A NARATIVE REVIEW.
- Author
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Hassan, Taimoor, Saeed, Sana, Ahmad, Ashfaq, Ahmed, Farooq, Ali, Yasir, and Khalid, Shehzad
- Subjects
- *
BIOPOLYMERS , *CLINICAL medicine , *POLYMERS , *MEDICAL polymers - Abstract
A plethora of synthetic, hybrid and biological polymers are widely being used in medical applications. Many polymers are helpful in our civic activities. Their peculiar chemical, physical, and biological properties are applicable in multiple domains of life from engineering to medicine. This review specifically addresses the novel polymers and their applications in clinical medicine. It has been reported by the researchers that, synthetic polymers are not only playing tremendous roles in micro and macro medical-industry but these also play a remarkable role at nano levels as nano-drug carriers in pharmaceuticals. In this review, we will give a brief introduction of polymers and how they are widely being used in medicinal interventions. We will further shed light on the future prospects of polymers with an updated version. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
6. Synthesis of Poly Ester Amide with Amino Acids Function as Drug Polymers.
- Author
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Aziz, Manal A., Mohammed, Abeer A. R., and Diab, Abdul K. S.
- Subjects
- *
MEDICAL polymers , *POLYCONDENSATION , *POLYMERS , *DIOXANE , *MOIETIES (Chemistry) - Abstract
In this work, new polymers were synthesized by condensation polymerization and reacted with sulfonail amide to get drug polymers (poly ester amide) at 90C°using mixture of DMF & dioxane (1:1). Synthetic biomedical polymers and their derivatives are frequently utilised in medical and pharmaceutical purposes. Recently, Specific consideration has been showed to chemical features of biocompatible polymers, since these polymers have an benefit of being quickly hydrolyzed into easy get rid of and non-toxic results which can be subsequently removed via metabolic pathways. The new polymer which has bioactive group's moiety were determined physical features by FTIR & UV techniques. In addition to its biochemical properties. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
7. Recent Advances in Nanomaterials for Asthma Treatment
- Author
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Xu Zuo, Xiaoping Guo, Yinuo Gu, Haoyu Zheng, Zhengjie Zhou, Xinlei Wang, Shengyu Jiang, Guoqiang Wang, Caina Xu, and Fang Wang
- Subjects
biomedical polymers ,asthma ,nanoparticles ,drug delivery ,nanomaterials ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Asthma is a chronic airway inflammatory disease with complex mechanisms, and these patients often encounter difficulties in their treatment course due to the heterogeneity of the disease. Currently, clinical treatments for asthma are mainly based on glucocorticoid-based combination drug therapy; however, glucocorticoid resistance and multiple side effects, as well as the occurrence of poor drug delivery, require the development of more promising treatments. Nanotechnology is an emerging technology that has been extensively researched in the medical field. Several studies have shown that drug delivery systems could significantly improve the targeting, reduce toxicity and improve the bioavailability of drugs. The use of multiple nanoparticle delivery strategies could improve the therapeutic efficacy of drugs compared to traditional delivery methods. Herein, the authors presented the mechanisms of asthma development and current therapeutic methods. Furthermore, the design and synthesis of different types of nanomaterials and micromaterials for asthma therapy are reviewed, including polymetric nanomaterials, solid lipid nanomaterials, cell membranes-based nanomaterials, and metal nanomaterials. Finally, the challenges and future perspectives of these nanomaterials are discussed to provide guidance for further research directions and hopefully promote the clinical application of nanotherapeutics in asthma treatment.
- Published
- 2022
- Full Text
- View/download PDF
8. Surface Properties of Polymeric Composites with Silver Nanoparticles.
- Author
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Ziąbka, Magdalena and Dziadek, Michał
- Subjects
POLYMERIC composites ,SILVER nanoparticles ,ANTIBACTERIAL agents ,ANTI-infective agents ,NANOSTRUCTURED materials - Abstract
The aim of this study was to investigate the surface properties of polymeric composites and the osteoblastic cell behaviour set in direct contact with the biomaterials tested. The surface properties were evaluated before and after 6-month incubation in an in vitro environment. The composite materials were prepared by means of extrusion and injection moulding. Three commercially available thermoplastic polymers (ABS (poly)acrylonitrile butadiene styrene) were used as composite matrices. Antibacterial silver nanoparticles (AgNPs) were added as a modifying phase. Surface properties of the materials tested, such as: wettability, roughness and microstructure, were determined. Furthermore the morphology of Saos-2 human osteoblastic cells in direct contact with the composite materials was assessed after the 7-day culture. The addition of silver nanoparticles caused minor changes in the wettability and roughness values. As light modification, the silver nanoparticles influenced the microstructure. The osteoblasts displayed the proper morphology and they evenly settled on the surface of the pure polymer and composite materials, which indicated the material cytocompatibility. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
9. Efficient Diethylzinc/Gallic Acid and Diethylzinc/Gallic Acid Ester Catalytic Systems for the Ring-Opening Polymerization of rac-Lactide
- Author
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Karolina Żółtowska, Urszula Piotrowska, Ewa Oledzka, and Marcin Sobczak
- Subjects
biomedical polymers ,polylactide ,ring-opening polymerization ,zinc-based catalysts ,gallic acid ,propyl gallate ,Organic chemistry ,QD241-441 - Abstract
Polylactide (PLA) represents one of the most promising biomedical polymers due to its biodegradability, bioresorbability and good biocompatibility. This work highlights the synthesis and characterization of PLAs using novel diethylzinc/gallic acid (ZnEt2/GAc) and diethylzinc/propyl gallate (ZnEt2/PGAc) catalytic systems that are safe for human body. The results of the ring-opening polymerization (ROP) of rac-lactide (rac-LA) in the presence of zinc-based catalytic systems have shown that, depending on the reaction conditions, “predominantly isotactic”, disyndiotactic or atactic PLA can be obtained. Therefore, the controlled and stereoselective ROP of rac-LA is discussed in detail in this paper.
- Published
- 2015
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- View/download PDF
10. Assessment of the biocompatibility of PHB and P(HB-HV)
- Author
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Kennedy, Joanne Elizabeth
- Subjects
610.28 ,Biomedical polymers - Published
- 1990
11. Development and Characterization of Polyester and Acrylate-Based Composites with Hydroxyapatite and Halloysite Nanotubes for Medical Applications
- Author
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Elena Torres, Ivan Dominguez-Candela, Sergio Castello-Palacios, Anna Vallés-Lluch, and Vicent Fombuena
- Subjects
biomedical polymers ,hydroxyapatite ,halloysite ,mechanical properties ,Organic chemistry ,QD241-441 - Abstract
We aimed to study the distribution of hydroxyapatite (HA) and halloysite nanotubes (HNTs) as fillers and their influence on the hydrophobic character of conventional polymers used in the biomedical field. The hydrophobic polyester poly (ε-caprolactone) (PCL) was blended with its more hydrophilic counterpart poly (lactic acid) (PLA) and the hydrophilic acrylate poly (2-hydroxyethyl methacrylate) (PHEMA) was analogously compared to poly (ethyl methacrylate) (PEMA) and its copolymer. The addition of HA and HNTs clearly improve surface wettability in neat samples (PCL and PHEMA), but not that of the corresponding binary blends. Energy-dispersive X-ray spectroscopy mapping analyses show a homogenous distribution of HA with appropriate Ca/P ratios between 1.3 and 2, even on samples that were incubated for seven days in simulated body fluid, with the exception of PHEMA, which is excessively hydrophilic to promote the deposition of salts on its surface. HNTs promote large aggregates on more hydrophilic polymers. The degradation process of the biodegradable polyester PCL blended with PLA, and the addition of HA and HNTs, provide hydrophilic units and decrease the overall crystallinity of PCL. Consequently, after 12 weeks of incubation in phosphate buffered saline the mass loss increases up to 48% and mechanical properties decrease above 60% compared with the PCL/PLA blend.
- Published
- 2020
- Full Text
- View/download PDF
12. Application of Diethylzinc/Propyl Gallate Catalytic System for Ring-Opening Copolymerization of rac-Lactide and ε-Caprolactone
- Author
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Rafał Wyrębiak, Ewa Oledzka, Ramona Figat, and Marcin Sobczak
- Subjects
ring-opening polymerization ,zinc catalyst ,ε-caprolactone ,rac-lactide ,biodegradable polyesters ,biomedical polymers ,Organic chemistry ,QD241-441 - Abstract
Biodegradable polyesters gain significant attention because of their wide potential biomedical applications. The ring-opening polymerization method is widely used to obtain such polymers, due to high yields and advantageous properties of the obtained material. The preparation of new, effective, and bio-safe catalytic systems for the synthesis of biomedical polymers is one of the main directions of the research in modern medical chemistry. The new diethylzinc/propyl gallate catalytic system was first used in the copolymerization of ε-caprolactone and rac-lactide. In this paper, the activity of the new zinc-based catalytic system in the copolymerization of cyclic esters depending on the reaction conditions was described. The microstructure analysis of the obtained copolyesters and their toxicity studies were performed. Resulted copolyesters were characterized by low toxicity, moderate dispersity (1.19−1.71), varying randomness degree (0.18−0.83), and average molar mass (5300−9800 Da).
- Published
- 2019
- Full Text
- View/download PDF
13. Synthesis and antimicrobial activity of α-aminophosphonates containing chitosan moiety
- Author
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El-Refaie S. Kenawy, Mohamed M. Azaam, and Khalil M. Saad-Allah
- Subjects
α-Aminophosphonate ,Chitosan ,Antimicrobial polymers ,Biomedical polymers ,Chemistry ,QD1-999 - Abstract
A novel series of α-aminophosphonates containing chitosan moiety was obtained in high yields from reactions of chitosan with aromatic aldehydes and triphenylphosphite in the presence of lithium perchlorate as a catalyst. The structures of the synthesized compounds were confirmed by IR and 1H NMR spectral data. Compounds (1–4) showed high antimicrobial activities against Escherichia coli (NCIM2065), Serratia marcescens, Enterobacter cloacae, Shigella dysenteriae, Salmonella enterica and Proteus vulgaris as Gram-negative bacteria, Bacillus subtilis (PC1219) and Staphylococcus aureus (ATCC25292) as Gram-positive bacteria and Candida albicans as a fungus, at low concentrations (2.5–10 mg/mL).
- Published
- 2015
- Full Text
- View/download PDF
14. Novel Zinc-Catalytic Systems for Ring-Opening Polymerization of ε-Caprolactone
- Author
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Karolina Żółtowska, Marcin Sobczak, and Ewa Olędzka
- Subjects
poly(ε-caprolactone) ,aliphatic polyesters ,biomedical polymers ,ring-opening polymerization ,diethylzinc ,Organic chemistry ,QD241-441 - Abstract
Polycaprolactone (PCL) is a biodegradable synthetic polymer that is currently widely used in many pharmaceutical and medical applications. In this paper we describe the coordination ring-opening polymerization of ε-caprolactone in the presence of two newly synthesized catalytic systems: diethylzinc/gallic acid and diethylzinc/propyl gallate. The chemical structures of the obtained PCLs were characterized by 1H- or 13C-NMR, FTIR spectroscopy and MALDI TOF mass spectrometry. The average molecular weight of the resulting polyesters was analysed by gel permeation chromatography and a viscosity method. The effects of temperature, reaction time and type of catalytic system on the polymerization process were examined. Linear PCLs with defined average molecular weight were successfully obtained. Importantly, in some cases the presence of macrocyclic products was not observed during the polymerization process. This study provides an effective method for the synthesis of biodegradable polyesters for medical and pharmaceutical applications due to the fact that gallic acid/propyl gallate are commonly used in the pharmaceutical industry.
- Published
- 2015
- Full Text
- View/download PDF
15. Enzymatic Polymerization of Cyclic Monomers in Ionic Liquids as a Prospective Synthesis Method for Polyesters Used in Drug Delivery Systems
- Author
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Urszula Piotrowska and Marcin Sobczak
- Subjects
biomedical polymers ,macromolecular conjugates of drugs ,enzymatic ring opening polymerization ,ionic liquids ,biodegradable polyesters ,drug delivery systems ,Organic chemistry ,QD241-441 - Abstract
Biodegradable or bioresorbable polymers are commonly used in various pharmaceutical fields (e.g., as drug delivery systems, therapeutic systems or macromolecular drug conjugates). Polyesters are an important class of polymers widely utilized in pharmacy due to their biodegradability and biocompatibility features. In recent years, there has been increased interest in enzyme-catalyzed ring-opening polymerization (e-ROP) of cyclic esters as an alternative method of preparation of biodegradable or bioresorbable polymers. Ionic liquids (ILs) have been presented as green solvents in enzymatic ring-opening polymerization. The activity, stability, selectivity of enzymes in ILs and the ability to catalyze polyester synthesis under these conditions are discussed. Overall, the review demonstrates that e-ROP of lactones or lactides could be an effective method for the synthesis of useful biomedical polymers.
- Published
- 2014
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16. Polymeric Systems of Antimicrobial Peptides—Strategies and Potential Applications
- Author
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Ewa Olędzka, Ryszard Kozłowski, Cezary Dębek, and Marcin Sobczak
- Subjects
biomedical polymers ,peptides with antimicrobial activity ,polymeric carriers ,biodegradable polymers ,Organic chemistry ,QD241-441 - Abstract
The past decade has seen growing interest in the investigation of peptides with antimicrobial activity (AMPs). One approach utilized in infection control is incorporation of antimicrobial agents conjugated with the polymers. This review presents the recent developments on polymeric AMP carriers and their potential applications in the biomedical and pharmaceutical fields.
- Published
- 2013
- Full Text
- View/download PDF
17. Characterization of Aliphatic Polyesters Synthesized via Enzymatic Ring-Opening Polymerization in Ionic Liquids.
- Author
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Piotrowska, Urszula, Sobczak, Marcin, and Oledzka, Ewa
- Subjects
- *
ALIPHATIC compounds , *POLYESTERS , *CHEMICAL synthesis , *IONIC liquids , *RING-opening polymerization - Abstract
To evaluate the effects of ionic liquids (ILs) on the microstructural features of aliphatic polyesters for biomedical applications, a series of copolymers were synthesized by lipase ring opening polymerization of rac-lactide (rac-LA) and "-caprolactone (CL). The chemical structures of resulting polymers were characterized by 1H- and 13C-NMR and the average molecular weight (Mn) and dispersity index were characterized by gel permeation chromatography. The structure of the copolymers confirms the presence of linear polymer chains with end-functional hydroxyl groups allowing covalent coupling of the therapeutic agents. Chain microstructure of copolymers indicates the presence of both random and block copolymers depending on the synthesis conditions. Moreover, it was found that CL is the most active co-monomer during copolymerization which enhances the polymerizability of rac-LA and allows to obtain higher Mn of the copolymers. The results demonstrate that ILs could be promising solvents in synthesis of aliphatic esters for biomedical applications. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
18. Chitosan-Modified Cellulosic Nonwoven for Application in Gynecology. Impact of the Modification Upon Chemical Purity, Structure and Antibacterial Properties.
- Author
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Gzyra-Jagieła, Karolina, Jóźwicka, Jolanta, Gutowska, Agnieszka, Pałys, Beata, and Kaźmierczak, Dorota
- Subjects
CHITOSAN ,NONWOVEN textiles ,GYNECOLOGY ,ANTIBACTERIAL agents ,NANOPARTICLES - Abstract
Physical-chemical, morphological and physical-mechanical characterization was made for cellulose nonwoven modified with chitosan nanoparticles with a view to their possible use in medicine as gynecological tampons. It was an aim of the work to assess the impact of the addition of chitosan nanoparticles upon the biological activity and toxicity of the materials prepared. Methodology was prepared for the examination of the gynecological devices in the range of their useful properties, notably the mechanical strength, surface density and absorption. Aqueous extracts were examined after an extraction process that simulated standard use of the medical device, and after a surplus extraction. The content of water-soluble-, surfactant- and reductive substances was estimated as well as the contents of heavy metals like cadmium, lead, zinc and mercury by the ASA method. Morphology examination permitted to assess the impact of the extraction processes on the fibre structure. Antibacterial activity against Escherichia coli and Staphylococcus aureus, and antifungal activity against Candida albicans was measured. Altogether examinations were made to assess whether the cellulosic nonwoven modified with chitosan nanoparticles meets the demands of medical devices and lends itself to the manufacture of tampons. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
19. A Green Method for Processing Polymers using Dense Gas Technology
- Author
-
Roshan B. Yoganathan, Raffaella Mammucari, and Neil R. Foster
- Subjects
dense gas technology ,polymer processing ,green technology ,biomedical polymers ,drug delivery system ,polymer blends ,polymerization ,polycarbonate ,polycaprolactone ,ibuprofen ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Dense CO2 can be used as an environmentally-benign polymer processing medium because of its liquid-like densities and gas-like mass transfer properties.In this work, polymer bio-blends of polycarbonate (PC), a biocompatible polymer, and polycaprolactone (PCL), a biodegradable polymer were prepared. Dense CO2 was used as a reaction medium for the melt-phase PC polymerization in the presence of dense CO2-swollen PCL particles and this method was used to prepare porous PC/PCL blends. To extend the applicability of dense CO2 to the biomedical industry and polymer blend processing, the impregnation of ibuprofen into the blend was conducted and subsequent dissolution characteristics were observed.
- Published
- 2010
- Full Text
- View/download PDF
20. Efficient Diethylzinc/Gallic Acid and Diethylzinc/Gallic Acid Ester Catalytic Systems for the Ring-Opening Polymerization of rac-Lactide.
- Author
-
Żółtowska, ,2Karolina, Piotrowska, Urszula, Oledzka, Ewa, and Sobczak, Marcin
- Subjects
- *
DEPOLYMERIZATION , *DIETHYLZINC , *POLYMERIZATION , *CHEMICAL reactions , *CATALYSIS - Abstract
Polylactide (PLA) represents one of the most promising biomedical polymers due to its biodegradability, bioresorbability and good biocompatibility. This work highlights the synthesis and characterization of PLAs using novel diethylzinc/gallic acid (ZnEt2/GAc) and diethylzinc/propyl gallate (ZnEt2/PGAc) catalytic systems that are safe for human body. The results of the ring-opening polymerization (ROP) of rac-lactide (rac-LA) in the presence of zinc-based catalytic systems have shown that, depending on the reaction conditions, "predominantly isotactic", disyndiotactic or atactic PLA can be obtained. Therefore, the controlled and stereoselective ROP of rac-LA is discussed in detail in this paper. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
21. Chemical Purity of Biodegradable Medical-Grade Fibres of Aliphatic Copolyesters.
- Author
-
Gzyra-Jagieła, Karolina, Jóźwicka, Jolanta, Gutowska, Agnieszka, Twarowska-Schmidt, Krystyna, and Ciechańska, Danuta
- Subjects
BIODEGRADABLE products ,ALIPHATIC compounds ,SPINNING (Textiles) ,MEDICAL polymers ,NONIONIC surfactants ,PHYSICAL & theoretical chemistry - Abstract
Fibres prepared on an experimental scale from biodegradable copolyester of glycolide and lactide (PLGA) and from PLGA with the addition of 9% of atactic poly([R,S]-3-hydroxybutyrate (PLGA+a-PHB) were characterised to assess their possible use in the preparation of surgery sutures. Commercial spinfinish Estesol PF 790 (Bozzetto Group, Italy) was applied on the fibres in the spinning step. A method was prepared for an organic extraction of the spinfinish from the PLGA fibres, and the process efficacy was assessed by scanning electron microscopy (SEM) and by estimating chemical purity. With spinfinish removed, the fibres were subjected to an extraction process which simulated the utilisation of the products in an aqueous medium. The aqueous extracts were analysed to estimate contamination contents. Also estimated was the time in which the fibres degrade when subjected to surplus extraction in an aqueous medium. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
22. Relationship between the Stereocomplex Crystallization Behavior and Mechanical Properties of PLLA/PDLA Blends
- Author
-
C. K. Hong and Hye-Seon Park
- Subjects
Thermogravimetric analysis ,Materials science ,Polymers and Plastics ,Biomedical polymers ,PDLA ,Nucleation ,Organic chemistry ,General Chemistry ,Dynamic mechanical analysis ,stereocomplex crystallization ,mechanical properties ,PLLA ,Article ,law.invention ,Differential scanning calorimetry ,QD241-441 ,homo crystallization ,Chemical engineering ,Optical microscope ,law ,Crystallization ,Tensile testing - Abstract
Poly (l-lactic acid) (PLLA) is a promising biomedical polymer material with a wide range of applications. The diverse enantiomeric forms of PLLA provide great opportunities for thermal and mechanical enhancement through stereocomplex formation. The addition of poly (d-lactic acid) (PDLA) as a nucleation agent and the formation of stereocomplex crystallization (SC) have been proven to be an effective method to improve the crystallization and mechanical properties of the PLLA. In this study, PLLA was blended with different amounts of PDLA through a melt blending process and their properties were calculated. The effect of the PDLA on the crystallization behavior, thermal, and mechanical properties of PLLA were investigated systematically by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), polarized optical microscopy (POM), dynamic mechanical analysis (DMA), and tensile test. Based on our findings, SC formed easily when PDLA content was increased, and acts as nucleation sites. Both SC and homo crystals (HC) were observed in the PLLA/PDLA blends. As the content of PDLA increased, the degree of crystallization increased, and the mechanical strength also increased.
- Published
- 2021
- Full Text
- View/download PDF
23. 3D printing of polyether-ether-ketone for biomedical applications
- Author
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Chander Prakash, Seeram Ramakrishna, and Sunpreet Singh
- Subjects
chemistry.chemical_classification ,Polymers and Plastics ,business.industry ,Computer science ,Biomedical polymers ,Organic Chemistry ,General Physics and Astronomy ,3D printing ,Nanotechnology ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Polyether ether ketone ,chemistry.chemical_compound ,chemistry ,Research community ,Materials Chemistry ,Peek ,0210 nano-technology ,business - Abstract
Despite the rapid progress of several three-dimensional (3D) printing technologies, there exists a critical barrier in-term of processability of high performance materials. Polyether-ether-ketone (PEEK) is known for its higher mechanical properties, chemical stability, biological stability and biocompatibility suitable for certain biomedical applications. Examining a growing body of scientific literature on 3D printing of biomedical polymers indicates that most of the studies are conducted using biomedical polymers such as poly-carpolactone, poly-lactic acid, poly-glycolic acid, polyethylene and polyurethanes. However, studies on 3D Printing of PEEK is sparse owing to the higher temperatures needed for melting, lacking of availability of suitable feedstock, concerns over poor adhesion between layers, and time consuming and uneconomical processing steps. Given the unique nature of PEEK class of polymers, this manuscript closely examines 3D printability of PEEK for a range of biomedical applications. This manuscript also presents ideas, feasible solutions and enabling scientific mechanisms to improve the 3D printability of PEEK. This article will help the research community to strengthen the conceptual knowledge and insights on the 3D printing of PEEK based medical devices and tools, and future possibilities.
- Published
- 2019
24. Possible Role of Biomedical Polymers in COVID-19 Journey: A Short Review
- Author
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Jawad Akram Jassim
- Subjects
Engineering ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Biomedical polymers ,Nanotechnology ,business - Published
- 2021
25. Near-Field Electrospinning and Melt Electrowriting of Biomedical Polymers—Progress and Limitations
- Author
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William E. King and Gary L. Bowlin
- Subjects
chemistry.chemical_classification ,Scaffold ,Materials science ,Polymers and Plastics ,fiber write ,Biomedical polymers ,near-field electrospinning ,Near and far field ,Nanotechnology ,General Chemistry ,Polymer ,Bending ,Review ,Electrospinning ,biomedical polymer ,lcsh:QD241-441 ,chemistry ,lcsh:Organic chemistry ,Electric field ,melt electrowrite ,Fiber - Abstract
Near-field electrospinning (NFES) and melt electrowriting (MEW) are the process of extruding a fiber due to the force exerted by an electric field and collecting the fiber before bending instabilities occur. When paired with precise relative motion between the polymer source and the collector, a fiber can be directly written as dictated by preprogrammed geometry. As a result, this precise fiber control results in another dimension of scaffold tailorability for biomedical applications. In this review, biomedically relevant polymers that to date have manufactured fibers by NFES/MEW are explored and the present limitations in direct fiber writing of standardization in published setup details, fiber write throughput, and increased ease in the creation of complex scaffold geometries are discussed.
- Published
- 2021
26. Synthesis and antimicrobial activity of α-aminophosphonates containing chitosan moiety.
- Author
-
Kenawy, El-Refaie S., Azaam, Mohamed M., and Saad-Allah, Khalil M.
- Abstract
A novel series of α-aminophosphonates containing chitosan moiety was obtained in high yields from reactions of chitosan with aromatic aldehydes and triphenylphosphite in the presence of lithium perchlorate as a catalyst. The structures of the synthesized compounds were confirmed by IR and 1 H NMR spectral data. Compounds ( 1 – 4 ) showed high antimicrobial activities against Escherichia coli (NCIM2065), Serratia marcescens , Enterobacter cloacae , Shigella dysenteriae , Salmonella enterica and Proteus vulgaris as Gram-negative bacteria, Bacillus subtilis (PC1219) and Staphylococcus aureus (ATCC25292) as Gram-positive bacteria and Candida albicans as a fungus, at low concentrations (2.5–10 mg/mL). [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
27. Novel Zinc-Catalytic Systems for Ring-Opening Polymerization of ε-Caprolactone.
- Author
-
Żółtowska, Karolina, Sobczak, Marcin, and Olędzka, Ewa
- Subjects
- *
ZINC catalysts , *RING-opening polymerization , *CAPROLACTONES , *GALLIC acid , *DIETHYLZINC , *PROPYL gallate , *CHEMICAL structure , *NUCLEAR magnetic resonance - Abstract
Polycaprolactone (PCL) is a biodegradable synthetic polymer that is currently widely used in many pharmaceutical and medical applications. In this paper we describe the coordination ring-opening polymerization of e-caprolactone in the presence of two newly synthesized catalytic systems: diethylzinc/gallic acid and diethylzinc/propyl gallate. The chemical structures of the obtained PCLs were characterized by 1H- or 13C-NMR, FTIR spectroscopy and MALDI TOF mass spectrometry. The average molecular weight of the resulting polyesters was analysed by gel permeation chromatography and a viscosity method. The effects of temperature, reaction time and type of catalytic system on the polymerization process were examined. Linear PCLs with defined average molecular weight were successfully obtained. Importantly, in some cases the presence of macrocyclic products was not observed during the polymerization process. This study provides an effective method for the synthesis of biodegradable polyesters for medical and pharmaceutical applications due to the fact that gallic acid/propyl gallate are commonly used in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
28. Development and Characterization of Polyester and Acrylate-Based Composites with Hydroxyapatite and Halloysite Nanotubes for Medical Applications
- Author
-
Universitat Politècnica de València. Instituto Universitario de Telecomunicación y Aplicaciones Multimedia - Institut Universitari de Telecomunicacions i Aplicacions Multimèdia, Universitat Politècnica de València. Departamento de Termodinámica Aplicada - Departament de Termodinàmica Aplicada, Universitat Politècnica de València. Departamento de Ingeniería Química y Nuclear - Departament d'Enginyeria Química i Nuclear, Universitat Politècnica de València, Torres, Elena, Domínguez-Candela, Iván, Castelló-Palacios, Sergio, Vallés Lluch, Ana, Fombuena, Vicent, Universitat Politècnica de València. Instituto Universitario de Telecomunicación y Aplicaciones Multimedia - Institut Universitari de Telecomunicacions i Aplicacions Multimèdia, Universitat Politècnica de València. Departamento de Termodinámica Aplicada - Departament de Termodinàmica Aplicada, Universitat Politècnica de València. Departamento de Ingeniería Química y Nuclear - Departament d'Enginyeria Química i Nuclear, Universitat Politècnica de València, Torres, Elena, Domínguez-Candela, Iván, Castelló-Palacios, Sergio, Vallés Lluch, Ana, and Fombuena, Vicent
- Abstract
[EN] We aimed to study the distribution of hydroxyapatite (HA) and halloysite nanotubes (HNTs) as fillers and their influence on the hydrophobic character of conventional polymers used in the biomedical field. The hydrophobic polyester poly (¿-caprolactone) (PCL) was blended with its more hydrophilic counterpart poly (lactic acid) (PLA) and the hydrophilic acrylate poly (2-hydroxyethyl methacrylate) (PHEMA) was analogously compared to poly (ethyl methacrylate) (PEMA) and its copolymer. The addition of HA and HNTs clearly improve surface wettability in neat samples (PCL and PHEMA), but not that of the corresponding binary blends. Energy-dispersive X-ray spectroscopy mapping analyses show a homogenous distribution of HA with appropriate Ca/P ratios between 1.3 and 2, even on samples that were incubated for seven days in simulated body fluid, with the exception of PHEMA, which is excessively hydrophilic to promote the deposition of salts on its surface. HNTs promote large aggregates on more hydrophilic polymers. The degradation process of the biodegradable polyester PCL blended with PLA, and the addition of HA and HNTs, provide hydrophilic units and decrease the overall crystallinity of PCL. Consequently, after 12 weeks of incubation in phosphate buffered saline the mass loss increases up to 48% and mechanical properties decrease above 60% compared with the PCL/PLA blend.
- Published
- 2020
29. Enzymatic Polymerization of Cyclic Monomers in Ionic Liquids as a Prospective Synthesis Method for Polyesters Used in Drug Delivery Systems.
- Author
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Piotrowska, Urszula and Sobczak, Marcin
- Subjects
- *
BIODEGRADABLE materials , *RING-opening polymerization , *POLYESTERS , *DRUG delivery systems , *MACROMOLECULAR dynamics , *BIOCOMPATIBILITY , *MEDICAL polymers , *IONIC liquids - Abstract
Biodegradable or bioresorbable polymers are commonly used in various pharmaceutical fields (e.g., as drug delivery systems, therapeutic systems or macromolecular drug conjugates). Polyesters are an important class of polymers widely utilized in pharmacy due to their biodegradability and biocompatibility features. In recent years, there has been increased interest in enzyme-catalyzed ring-opening polymerization (e-ROP) of cyclic esters as an alternative method of preparation of biodegradable or bioresorbable polymers. Ionic liquids (ILs) have been presented as green solvents in enzymatic ring-opening polymerization. The activity, stability, selectivity of enzymes in ILs and the ability to catalyze polyester synthesis under these conditions are discussed. Overall, the review demonstrates that e-ROP of lactones or lactides could be an effective method for the synthesis of useful biomedical polymers. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
30. Development and Characterization of Polyester and Acrylate-Based Composites with Hydroxyapatite and Halloysite Nanotubes for Medical Applications
- Author
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Vicent Fombuena, Elena Torres, Sergio Castello-Palacios, Anna Vallés-Lluch, and Ivan Dominguez-Candela
- Subjects
Polymers and Plastics ,Simulated body fluid ,Mechanical properties ,macromolecular substances ,engineering.material ,mechanical properties ,Methacrylate ,Halloysite ,INGENIERIA QUIMICA ,Article ,Hydroxyapatite ,lcsh:QD241-441 ,Crystallinity ,chemistry.chemical_compound ,lcsh:Organic chemistry ,Copolymer ,halloysite ,chemistry.chemical_classification ,Acrylate ,technology, industry, and agriculture ,hydroxyapatite ,Biomedical polymers ,General Chemistry ,Polymer ,equipment and supplies ,Polyester ,chemistry ,Chemical engineering ,biomedical polymers ,MAQUINAS Y MOTORES TERMICOS ,engineering - Abstract
[EN] We aimed to study the distribution of hydroxyapatite (HA) and halloysite nanotubes (HNTs) as fillers and their influence on the hydrophobic character of conventional polymers used in the biomedical field. The hydrophobic polyester poly (¿-caprolactone) (PCL) was blended with its more hydrophilic counterpart poly (lactic acid) (PLA) and the hydrophilic acrylate poly (2-hydroxyethyl methacrylate) (PHEMA) was analogously compared to poly (ethyl methacrylate) (PEMA) and its copolymer. The addition of HA and HNTs clearly improve surface wettability in neat samples (PCL and PHEMA), but not that of the corresponding binary blends. Energy-dispersive X-ray spectroscopy mapping analyses show a homogenous distribution of HA with appropriate Ca/P ratios between 1.3 and 2, even on samples that were incubated for seven days in simulated body fluid, with the exception of PHEMA, which is excessively hydrophilic to promote the deposition of salts on its surface. HNTs promote large aggregates on more hydrophilic polymers. The degradation process of the biodegradable polyester PCL blended with PLA, and the addition of HA and HNTs, provide hydrophilic units and decrease the overall crystallinity of PCL. Consequently, after 12 weeks of incubation in phosphate buffered saline the mass loss increases up to 48% and mechanical properties decrease above 60% compared with the PCL/PLA blend., Dominguez-Candela thanks the Universitat Politècnica de València for the financial support through an FPI-UPV grant (PAID-01-19)
- Published
- 2020
- Full Text
- View/download PDF
31. The development of advanced smart polymer formulations for potential biomedical applications
- Author
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Halligan, Shane C., Geever, Luke M., Lyons, John G., Higginbotham, Clement L., and Athlone Institute of Technology
- Subjects
Materials Research Institute AIT ,Biomedical polymers ,Smart polymers - Abstract
In the past twenty years, a theme in the pharmaceutical industry is to move towards more efficient use of active pharmaceutical ingredients and the need for improved delivery systems. Smart polymers throughout the literature have been suggested for several different biomedical applications such as in-situ forming gels. Fundamentally, this work focuses on the application of temperature responsive polymers as a platforms for improved drug delivery systems. Poly (N-vinylcaprolactam) (PNVCL) is a biocompatible smart polymer that offers superior characteristics for various medical device applications. PNVCL phase transitions can be tailored in order to suit the requirements of current and next-generation devices.. Physically cross-linked Poly (N-vinylcaprolactam)-Vinyl acetate (PNVCL-VAc) copolymers were initially prepared by photopolymerisation. The structure of the polymers was established by Fourier transform infrared spectroscopy, nuclear magnetic resonance and gel permeation chromatography. A determination of the lower critical solution temperature (LCST) of the polymers in aqueous solution was achieved by employing four techniques: cloud point analysis, UV- spectroscopy, differential scanning calorimetry and rheometry. The sol-gel transition was established by the tube inversion method and by rheological analysis. The characteristics of PNVCL with the addition of VAc were determined and the effects on the phase transition were established. The PNVCL based polymers exhibited a decrease in the LCST as the composition of VAc increased. The sol-gel transition was found to be affected by the composition and concentration of the material. Sterilisation of PNVCL was investigated using an industrial scale electron beam sterilisation process. Physically cross-linked Poly (N-vinylcaprolactam)-Vinyl acetate (PNVCL-VAc) copolymers were prepared by photopolymerisation and were subsequently exposed to ionising radiation via electron beam technology. The mechanical characteristics and phase transitions of the physically cross-linked PNVCL samples were tailored by controlling the electron beam irradiation dose. Importantly PNVCL and PNVCL-VAc samples (5 wt% in solution) underwent a phase transition between 33-27 °C, following electron beam irradiation. Furthermore, all samples displayed a Young's Modulus between 1024-1517 MPa depending on the addition of copolymer and electron beam irradiation dose. The electron beam sterilisation process proved successful in enhancing/modifying many fundamental polymer properties, and this ability to formulate and sterilise in one step could prove a very attractive approach for many biomedical applications. Combining a smart polymer system with hot-melt extrusion (HME) could allow for a targeted hybrid drug delivery system. Initial melt processing trials were conducted to determine suitable parameters such as temperature, screw speed, drying time and particle size. PNVCL based smart polymers were successfully extruded; this was achieved through the use of the incorporation of PEG as a plasticiser. PNVCL based samples were subsequently melt processed on a pharmaceutical-grade extruder leading to modified mechanical and phase transition properties. It was observed via FTIR and GPC analysis that the chain length of the polymer increased and that chemical changes were occurring. Therefore, a washing step was developed to remove any unreacted monomers in the smart polymer matrix. This reactive processing approach was found to be extraordinarily efficient and easily adjustable to alter PNVCL properties. Melt processing of PNVCL opens new avenues and potential applications for modifications, such as polymerisation and the blending of different materials within the smart polymer matrix. PNVCL was subsequently used as a smart polymer carrier for Acetaminophen (APAP); Physically cross-linked PNVCL based polymers were prepared by photopolymerisation. Hot-melt extrusion was used as a fabrication technique to incorporate APAP into PNVCL matrix, in an attempt to develop smart drug delivery carriers. FTIR established the structure of the xxvi extrudates. Determination of the drug release profile was achieved by employing HPLC. The findings suggest that interactions between PNVCL and APAP varied, according to the drug-polymer ratios. This study is the first of its kind to report the use of temperature-responsive polymers via a melt processing approach.
- Published
- 2020
32. Polymeric Systems of Antimicrobial Peptides-Strategies and Potential Applications.
- Author
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Sobczak, Marcin, Dębek, Cezary, Olędzka, Ewa, and Kozłowski, Ryszard
- Subjects
- *
MEDICAL polymers , *ANTIMICROBIAL peptides , *ANTIMICROBIAL polymers , *ANTI-infective agents , *PREVENTION of communicable diseases - Abstract
The past decade has seen growing interest in the investigation of peptides with antimicrobial activity (AMPs). One approach utilized in infection control is incorporation of antimicrobial agents conjugated with the polymers. This review presents the recent developments on polymeric AMP carriers and their potential applications in the biomedical and pharmaceutical fields. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
33. Recent progress in nanocomposites of carbon dioxide fixation derived reproducible biomedical polymers.
- Author
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Liu X, Jiang Z, Xing D, Yang Y, Li Z, and Sun Z
- Abstract
In recent years, the environmental problems accompanying the extensive application of biomedical polymer materials produced from fossil fuels have attracted more and more attentions. As many biomedical polymer products are disposable, their life cycle is relatively short. Most of the used or overdue biomedical polymer products need to be burned after destruction, which increases the emission of carbon dioxide (CO
2 ). Developing biomedical products based on CO2 fixation derived polymers with reproducible sources, and gradually replacing their unsustainable fossil-based counterparts, will promote the recycling of CO2 in this field and do good to control the greenhouse effect. Unfortunately, most of the existing polymer materials from renewable raw materials have some property shortages, which make them unable to meet the gradually improved quality and property requirements of biomedical products. In order to overcome these shortages, much time and effort has been dedicated to applying nanotechnology in this field. The present paper reviews recent advances in nanocomposites of CO2 fixation derived reproducible polymers for biomedical applications, and several promising strategies for further research directions in this field are highlighted., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Liu, Jiang, Xing, Yang, Li and Sun.)- Published
- 2022
- Full Text
- View/download PDF
34. Application of Diethylzinc/Propyl Gallate Catalytic System for Ring-Opening Copolymerization of rac-Lactide and ε-Caprolactone
- Author
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Marcin Sobczak, Rafal Wyrebiak, Ewa Oledzka, and Ramona Figat
- Subjects
ring-opening polymerization ,Dispersity ,Pharmaceutical Science ,Ring-opening polymerization ,Analytical Chemistry ,lcsh:QD241-441 ,chemistry.chemical_compound ,lcsh:Organic chemistry ,Drug Discovery ,Copolymer ,Organic chemistry ,biomedical polymers ,Physical and Theoretical Chemistry ,rac-lactide ,ε-caprolactone ,Propyl gallate ,zinc catalyst ,Lactide ,biodegradable polyesters ,Organic Chemistry ,Diethylzinc ,Polyester ,chemistry ,Chemistry (miscellaneous) ,Molecular Medicine ,Caprolactone - Abstract
Biodegradable polyesters gain significant attention because of their wide potential biomedical applications. The ring-opening polymerization method is widely used to obtain such polymers, due to high yields and advantageous properties of the obtained material. The preparation of new, effective, and bio-safe catalytic systems for the synthesis of biomedical polymers is one of the main directions of the research in modern medical chemistry. The new diethylzinc/propyl gallate catalytic system was first used in the copolymerization of &epsilon, caprolactone and rac-lactide. In this paper, the activity of the new zinc-based catalytic system in the copolymerization of cyclic esters depending on the reaction conditions was described. The microstructure analysis of the obtained copolyesters and their toxicity studies were performed. Resulted copolyesters were characterized by low toxicity, moderate dispersity (1.19&ndash, 1.71), varying randomness degree (0.18&ndash, 0.83), and average molar mass (5300&ndash, 9800 Da).
- Published
- 2019
35. Development of a technical approach to modify the internal surface of biomedical tubes and other elongated small lumen macrodevices with parylene coating
- Author
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Chintan Desai and Norbert Laube
- Subjects
Materials science ,Biocompatibility ,Biomedical polymers ,02 engineering and technology ,Surfaces and Interfaces ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Thermal diffusivity ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Parylene coating ,Wear resistance ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,Silicone ,chemistry ,Gaseous diffusion ,Composite material ,0210 nano-technology ,Lumen (unit) - Abstract
A multitude of differently composed biomedical polymers has been researched for many years for their distinctive ease of production and wide range of applications. New technologies and new material characteristics have always evolved accordingly. The lumina of biomedical polymer tubes such as catheters, intravenous tubes, and biomedical microfluidic channels do not necessarily show the required biocompatibility and desired functionality. In such cases, the products are provided with additional inner liner or coatings to achieve the desired specific properties. Specific adjustments, for example, low friction coefficient, low gas diffusion resistance, wear resistance, and hydrophobicity, are key properties which are in focus for the improvement of biomedical surfaces. In this pilot study, a technical method was developed to deposit parylene-AF4 on the inner surface of silicone tubes with aspect ratios exceeding 78:1. Uncoated and parylene-AF4-coated silicone tubes were investigated in respect to the aforementioned physical properties. Compared to the uncoated tubes, the parylene-coated tubes showed superior quality with respect to friction coefficient, gas diffusivity as well as wear resistance. It could be demonstrated that the new technical approach is suitable to parylene-coat the inner surfaces of tubes with high aspect ratios thereby achieving conformal coatings.
- Published
- 2018
36. Nanoimprinting of biomedical polymers reduces candidal physical adhesion
- Author
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R.A. McKerlie, Nikolaj Gadegaard, Christopher J. Nile, Paul M. Reynolds, Hasanain K. A. Alalwan, Ranjith Rajendran, and Gordon Ramage
- Subjects
0301 basic medicine ,Antifungal Agents ,Polymethyl methacrylate ,Polymers ,Surface Properties ,Biomedical Engineering ,Pharmaceutical Science ,Medicine (miscellaneous) ,Bioengineering ,Nanotechnology ,02 engineering and technology ,Bacterial Adhesion ,03 medical and health sciences ,Candida albicans ,General Materials Science ,Nanotopography ,biology ,Chemistry ,Biomedical polymers ,Bioprinting ,Biofilm ,Adhesion ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Corpus albicans ,030104 developmental biology ,Biofilms ,Pathogenic yeast ,Molecular Medicine ,0210 nano-technology - Abstract
Management of fungal biofilms represents a significant challenge to healthcare. As a preventive approach, minimizing adhesion between indwelling medical devices and microorganisms would be an important step forward. This study investigated the anti-fouling capacity of engineered nanoscale topographies to the pathogenic yeast Candida albicans. Highly ordered arrays of nano-pit topographies were shown to significantly reduce the physical adherence capacity of C. albicans. This study shows a potential of nanoscale patterns to inhibit and prevent pathogenic biofilm formation on biomedical substrates.
- Published
- 2018
37. A Green Method for Processing Polymers using Dense Gas Technology.
- Author
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Yoganathan, Roshan B., Mammucari, Raffaella, and Foster, Neil R.
- Subjects
- *
POLYCARBONATES , *POLYMERIZATION , *POLYMERS , *MASS transfer , *BIODEGRADABLE plastics , *IBUPROFEN , *BIOMEDICAL materials , *CARBON dioxide , *DENSITY - Abstract
Dense CO2 can be used as an environmentally-benign polymer processing medium because of its liquid-like densities and gas-like mass transfer properties. In this work, polymer bio-blends of polycarbonate (PC), a biocompatible polymer, and polycaprolactone (PCL), a biodegradable polymer were prepared. Dense CO2 was used as a reaction medium for the melt-phase PC polymerization in the presence of dense CO2-swollen PCL particles and this method was used to prepare porous PC/PCL blends. To extend the applicability of dense CO2 to the biomedical industry and polymer blend processing, the impregnation of ibuprofen into the blend was conducted and subsequent dissolution characteristics were observed. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
38. Cellular response to oxygen containing biomedical polymers modified by Ar and He implantation.
- Author
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Manso, M., Navas, C. Rodríguez, Gilliland, D., Ruiz, P. García, and Rossi, F.
- Subjects
ION bombardment ,BIOPOLYMERS ,OXYGEN ,ETHYLENE - Abstract
Abstract: Ion beam modification is an attractive way to adapt the response of a biopolymer surface with the view to modifying cellular processes. In this work we performed Ar and He implantations into three oxygen-containing biomedical polymers: polycaprolactone (PCL), poly(ethylene glycol) (PEG) and poly(methyl methacrylate) (PMMA). An ion energy of 25keV was selected on the basis of singularities observed in simulated implantations. The implantations were carried out with fluences of 5×10
13 cm−2 considering also the ion current density as a source of differentiated damage. The modification of the polymer structure and composition was assayed by Fourier transform infrared spectroscopy, which confirmed the selectivity of the ion current density in producing polymer film damage. Biomedical assays denoted lack of structural stability on the PMMA surfaces. Surface analysis of proteins adsorbed from fetal bovine serum on ion-beam-modified PEG were realized by quartz-crystal microbalance with dissipation, which supported the film stabilization and anti-fouling behaviour of the films. On the other hand, protein adsorption studies on micropatterned PCL surfaces were performed by time-of-flight secondary ion mass spectroscopy and revealed a clear enhancement of protein immobilization in ion-beam-modified areas. The response of human mesenchymal stem cells to the surfaces was observed to depend on the biopolymer characteristics, showing adhesion inhibition onto He-modified PEG and specially enhanced colonization onto He-irradiated PCL. [Copyright &y& Elsevier]- Published
- 2007
- Full Text
- View/download PDF
39. Tailoring surface properties of biomedical polymers by implantation of Ar and He ions.
- Author
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Manso, M., Valsesia, A., Lejeune, M., Gilliland, D., Ceccone, G., and Rossi, F.
- Subjects
MEDICAL polymers ,ION implantation ,INTERMEDIATES (Chemistry) ,ETHYLENE glycol ,PHOTOELECTRON spectroscopy - Abstract
Abstract: Ion implantation at 25 and 100keV has been used as a tool for the modification of the surface properties of two biomedical polymers. The modulation induced by the different energy dispersion mechanisms of Ar and He have allowed satisfactory modifications for both the activation of the surfaces of chemically functional polycaprolactone (PCL) and the stabilization of anti-fouling poly(ethylene glycol) (PEG). In both cases the implantations have been performed at doses of 10
14 cm−2 by taking into account the effect of different current densities, which are shown to distinctly influence the fragmentation-crosslinking of the target polymers. The resultant films were characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, time of flight secondary ion mass spectroscopy and atomic force microscopy. Both shifts in zeta potential versus pH curves and the alteration of the polar components of the surface free energy (contact angle measurements) were correlated with the composition analysis. The response of the modified surfaces towards biomolecular interaction is demonstrated by the induction of preferential adsorption on irradiated PCL and the inhibited adsorption onto implanted PEG regions for selected oligopeptides and proteins. [Copyright &y& Elsevier]- Published
- 2005
- Full Text
- View/download PDF
40. Professor Sung Wan Kim – A pioneer in the world of pharmaceutics; biomedical polymer
- Author
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Teruo Okano and Kyung Sook Kim
- Subjects
Engineering ,lcsh:R5-920 ,business.industry ,lcsh:Cytology ,Biomedical polymers ,Biomedical Engineering ,Library science ,Biomaterials ,Pharmaceutics ,lcsh:QH573-671 ,business ,lcsh:Medicine (General) ,Letter to the Editor ,Developmental Biology - Published
- 2020
41. Developing bioactive composite materials for tissue replacement
- Author
-
Wang, Min
- Subjects
- *
COMPOSITE materials , *POLYMERS - Abstract
A variety of bioactive composites have been investigated over the last two decades as substitute materials for diseased or damaged tissues in the human body. In this paper, the rationale and strategy of developing these composites are given. Major factors influencing the production and performance of bioactive composites are discussed. Some promising composites for tissue replacement and regeneration are reviewed. On the basis of past experience and newly gained knowledge, composite materials with tailored mechanical and biological performance can be manufactured and used to meet various clinical requirements. [Copyright &y& Elsevier]
- Published
- 2003
- Full Text
- View/download PDF
42. Efficacy of several additives to modulate the phase behavior of biomedical polymers: A comprehensive and comparative outlook
- Author
-
Payal Narang and Pannuru Venkatesu
- Subjects
chemistry.chemical_classification ,animal structures ,Polymers ,Biomedical polymers ,Biomedical Technology ,Temperature ,Nanotechnology ,02 engineering and technology ,Surfaces and Interfaces ,Polymer ,Limiting ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Lower critical solution temperature ,0104 chemical sciences ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,chemistry ,Drug delivery ,Humans ,Thermoresponsive polymers in chromatography ,Physical and Theoretical Chemistry ,0210 nano-technology ,Ethylene glycol - Abstract
Several new classes of polymeric materials are being introduced with unique properties. Thermoresponsive polymers (TRPs) are one of the most fascinating and emerging class of biomaterials in biomedical research. The design of TRPs with good response to temperature and its ability to exhibit coil to globular transition behavior near to physiological temperature made them more promising materials in the field of biomaterials and biomedicines. Instead of numerous studies on TRPs, the mechanistic interplay among several additives and TRPs is still not understood clearly and completely. The lack of complete understanding of biomolecular interactions of various additives with TRPs is limiting their applications in interdisciplinary science as well as pharmaceutical industry. There is a great need to provide a collective and comprehensive information of various additives and their behavior on widely accepted biopolymers, TRPs such as poly(N-isopropylacrylamide) (PNIPAM), poly(vinyl methyl ether) (PVME), poly(N-vinylcaprolactum) (PVCL) and poly(ethylene glycol)-poly(propylene glycol)-poly(ethylene glycol) (PEG-PPG-PEG) in aqueous solution. Obviously, as the literature on the influence of various additives on TRPs is very vast, therefore we focus our review only on these four selected TRPs. Additives such as polyols, methylamines, surfactants and denaturants basically made the significant changes in water structure associated to polymer via their entropy variation which is the direct influence of their directly or indirectly binding abilities. Eventually, this review addresses a brief overview of the most recent literature of applications based phase behavior of four selected TRPs in response to external stimuli. The work enhances the knowledge for use of TRPs in the advanced development of drug delivery system and in many more pharmaceutical applications. These kinds of studies provide powerful impact in exploring the utility range of polymeric materials in various field of science.
- Published
- 2019
43. ScaffoldNet: Detecting and Classifying Biomedical Polymer-Based Scaffolds via a Convolutional Neural Network
- Author
-
Darlington Ahiale Akogo and Xavier-Lewis Palmer
- Subjects
Scaffold ,medicine.anatomical_structure ,business.industry ,Computer science ,Biomedical polymers ,technology, industry, and agriculture ,medicine ,Cortical bone ,Pattern recognition ,Artificial intelligence ,business ,Convolutional neural network - Abstract
We developed a Convolutional Neural Network model to identify and classify Airbrushed (alternatively known as Blow-spun), Electrospun and Steel Wire scaffolds. Our model ScaffoldNet is a 6-layer Convolutional Neural Network trained and tested on 3043 images of Airbrushed, Electrospun and Steel Wire scaffolds. The model takes in as input an imaged scaffold and then outputs the scaffold type (Airbrushed, Electrospun or Steel Wire) as predicted probabilities for the 3 classes. Our model scored a 99.44% Accuracy, demonstrating potential for adaptation to investigating and solving complex machine learning problems aimed at abstract spatial contexts, or in screening complex, biological, fibrous structures seen in cortical bone and fibrous shells.
- Published
- 2019
44. Efficient Diethylzinc/Gallic Acid and Diethylzinc/Gallic Acid Ester Catalytic Systems for the Ring-Opening Polymerization of rac-Lactide
- Author
-
Marcin Sobczak, Ewa Oledzka, Urszula Piotrowska, and Karolina Żółtowska
- Subjects
Polymers ,ring-opening polymerization ,Polyesters ,Pharmaceutical Science ,Crystallography, X-Ray ,Ring-opening polymerization ,Catalysis ,Article ,Polymerization ,Analytical Chemistry ,lcsh:QD241-441 ,chemistry.chemical_compound ,lcsh:Organic chemistry ,Coordination Complexes ,Drug Discovery ,Organometallic Compounds ,Humans ,Organic chemistry ,propyl gallate ,Gallic acid ,Physical and Theoretical Chemistry ,Propyl gallate ,chemistry.chemical_classification ,zinc-based catalysts ,Lactide ,Organic Chemistry ,Esters ,Polymer ,Diethylzinc ,chemistry ,Chemistry (miscellaneous) ,biomedical polymers ,polylactide ,gallic acid ,Molecular Medicine - Abstract
Polylactide (PLA) represents one of the most promising biomedical polymers due to its biodegradability, bioresorbability and good biocompatibility. This work highlights the synthesis and characterization of PLAs using novel diethylzinc/gallic acid (ZnEt2/GAc) and diethylzinc/propyl gallate (ZnEt2/PGAc) catalytic systems that are safe for human body. The results of the ring-opening polymerization (ROP) of rac-lactide (rac-LA) in the presence of zinc-based catalytic systems have shown that, depending on the reaction conditions, “predominantly isotactic”, disyndiotactic or atactic PLA can be obtained. Therefore, the controlled and stereoselective ROP of rac-LA is discussed in detail in this paper.
- Published
- 2015
45. Recent trends in bioinks for 3D printing
- Author
-
J. Gopinathan and Insup Noh
- Subjects
0301 basic medicine ,Engineering ,lcsh:Medical technology ,Biomedical Engineering ,Medicine (miscellaneous) ,3D printing ,Nanotechnology ,02 engineering and technology ,Review ,Regenerative medicine ,law.invention ,Biomaterials ,03 medical and health sciences ,Tissue engineering ,law ,3D bioprinting ,business.industry ,Biomedical polymers ,021001 nanoscience & nanotechnology ,Biocompatible material ,030104 developmental biology ,lcsh:R855-855.5 ,Bioink ,Self-healing hydrogels ,Ceramics and Composites ,0210 nano-technology ,business - Abstract
Background The worldwide demand for the organ replacement or tissue regeneration is increasing steadily. The advancements in tissue engineering and regenerative medicine have made it possible to regenerate such damaged organs or tissues into functional organ or tissue with the help of 3D bioprinting. The main component of the 3D bioprinting is the bioink, which is crucial for the development of functional organs or tissue structures. The bioinks used in 3D printing technology require so many properties which are vital and need to be considered during the selection. Combination of different methods and enhancements in properties are required to develop more successful bioinks for the 3D printing of organs or tissue structures. Main body This review consists of the recent state-of-art of polymer-based bioinks used in 3D printing for applications in tissue engineering and regenerative medicine. The subsection projects the basic requirements for the selection of successful bioinks for 3D printing and developing 3D tissues or organ structures using combinations of bioinks such as cells, biomedical polymers and biosignals. Different bioink materials and their properties related to the biocompatibility, printability, mechanical properties, which are recently reported for 3D printing are discussed in detail. Conclusion Many bioinks formulations have been reported from cell-biomaterials based bioinks to cell-based bioinks such as cell aggregates and tissue spheroids for tissue engineering and regenerative medicine applications. Interestingly, more tunable bioinks, which are biocompatible for live cells, printable and mechanically stable after printing are emerging with the help of functional polymeric biomaterials, their modifications and blending of cells and hydrogels. These approaches show the immense potential of these bioinks to produce more complex tissue/organ structures using 3D bioprinting in the future.
- Published
- 2018
46. Concise Review: Tailoring Bioengineered Scaffolds for Stem Cell Applications in Tissue Engineering and Regenerative Medicine
- Author
-
Hadi Hezaveh, Ellen A. Otte, Steffen Cosson, and Justin J. Cooper-White
- Subjects
Scaffold ,Biology ,Regenerative Medicine ,Regenerative medicine ,Tissue engineering ,Biomimetic Materials ,In vivo ,Animals ,Humans ,Enabling Technologies for Cell-Based Clinical Translation ,Tissue Engineering ,Tissue Scaffolds ,United States Food and Drug Administration ,business.industry ,Stem Cells ,Biomedical polymers ,Cell Biology ,General Medicine ,United States ,Cell biology ,Biotechnology ,Self-healing hydrogels ,Stem cell ,business ,Stem cell biology ,Developmental Biology - Abstract
The potential for the clinical application of stem cells in tissue regeneration is clearly significant. However, this potential has remained largely unrealized owing to the persistent challenges in reproducibly, with tight quality criteria, and expanding and controlling the fate of stem cells in vitro and in vivo. Tissue engineering approaches that rely on reformatting traditional Food and Drug Administration-approved biomedical polymers from fixation devices to porous scaffolds have been shown to lack the complexity required for in vitro stem cell culture models or translation to in vivo applications with high efficacy. This realization has spurred the development of advanced mimetic biomaterials and scaffolds to increasingly enhance our ability to control the cellular microenvironment and, consequently, stem cell fate. New insights into the biology of stem cells are expected to eventuate from these advances in material science, in particular, from synthetic hydrogels that display physicochemical properties reminiscent of the natural cell microenvironment and that can be engineered to display or encode essential biological cues. Merging these advanced biomaterials with high-throughput methods to systematically, and in an unbiased manner, probe the role of scaffold biophysical and biochemical elements on stem cell fate will permit the identification of novel key stem cell behavioral effectors, allow improved in vitro replication of requisite in vivo niche functions, and, ultimately, have a profound impact on our understanding of stem cell biology and unlock their clinical potential in tissue engineering and regenerative medicine.
- Published
- 2015
47. Characterization of Aliphatic Polyesters Synthesized via Enzymatic Ring-Opening Polymerization in Ionic Liquids
- Author
-
Marcin Sobczak, Urszula Piotrowska, and Ewa Oledzka
- Subjects
ring-opening polymerization ,Polyesters ,Proton Magnetic Resonance Spectroscopy ,Dispersity ,Pharmaceutical Science ,Ionic Liquids ,Biocompatible Materials ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Ring-opening polymerization ,Article ,Analytical Chemistry ,Polymerization ,Gel permeation chromatography ,chemistry.chemical_compound ,drug delivery systems ,Drug Discovery ,Polymer chemistry ,Copolymer ,aliphatic polyesters ,biomedical polymers ,ionic liquids ,lipases ,polylactide ,ε-caprolactone ,Organic chemistry ,Physical and Theoretical Chemistry ,Carbon-13 Magnetic Resonance Spectroscopy ,chemistry.chemical_classification ,Organic Chemistry ,Fatty Acids ,Polymer ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Polyester ,chemistry ,Chemistry (miscellaneous) ,Ionic liquid ,Molecular Medicine ,Molar mass distribution ,0210 nano-technology - Abstract
To evaluate the effects of ionic liquids (ILs) on the microstructural features of aliphatic polyesters for biomedical applications, a series of copolymers were synthesized by lipase ring opening polymerization of rac-lactide (rac-LA) and ε-caprolactone (CL). The chemical structures of resulting polymers were characterized by 1H- and 13C-NMR and the average molecular weight (Mn) and dispersity index were characterized by gel permeation chromatography. The structure of the copolymers confirms the presence of linear polymer chains with end-functional hydroxyl groups allowing covalent coupling of the therapeutic agents. Chain microstructure of copolymers indicates the presence of both random and block copolymers depending on the synthesis conditions. Moreover, it was found that CL is the most active co-monomer during copolymerization which enhances the polymerizability of rac-LA and allows to obtain higher Mn of the copolymers. The results demonstrate that ILs could be promising solvents in synthesis of aliphatic esters for biomedical applications.
- Published
- 2017
48. Development and Characterization of Polyester and Acrylate-Based Composites with Hydroxyapatite and Halloysite Nanotubes for Medical Applications.
- Author
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Torres, Elena, Dominguez-Candela, Ivan, Castello-Palacios, Sergio, Vallés-Lluch, Anna, and Fombuena, Vicent
- Subjects
- *
HALLOYSITE , *HYDROXYAPATITE , *NANOTUBES , *MEDICAL polymers , *POLYESTERS , *LACTIC acid , *X-ray spectroscopy - Abstract
We aimed to study the distribution of hydroxyapatite (HA) and halloysite nanotubes (HNTs) as fillers and their influence on the hydrophobic character of conventional polymers used in the biomedical field. The hydrophobic polyester poly (ε-caprolactone) (PCL) was blended with its more hydrophilic counterpart poly (lactic acid) (PLA) and the hydrophilic acrylate poly (2-hydroxyethyl methacrylate) (PHEMA) was analogously compared to poly (ethyl methacrylate) (PEMA) and its copolymer. The addition of HA and HNTs clearly improve surface wettability in neat samples (PCL and PHEMA), but not that of the corresponding binary blends. Energy-dispersive X-ray spectroscopy mapping analyses show a homogenous distribution of HA with appropriate Ca/P ratios between 1.3 and 2, even on samples that were incubated for seven days in simulated body fluid, with the exception of PHEMA, which is excessively hydrophilic to promote the deposition of salts on its surface. HNTs promote large aggregates on more hydrophilic polymers. The degradation process of the biodegradable polyester PCL blended with PLA, and the addition of HA and HNTs, provide hydrophilic units and decrease the overall crystallinity of PCL. Consequently, after 12 weeks of incubation in phosphate buffered saline the mass loss increases up to 48% and mechanical properties decrease above 60% compared with the PCL/PLA blend. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
49. Polymeric Systems of Antimicrobial Peptides—Strategies and Potential Applications
- Author
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Marcin Sobczak, Cezary Dębek, Ryszard Kozłowski, and Ewa Oledzka
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Chemistry ,Polymers ,Biomedical polymers ,Organic Chemistry ,Antimicrobial peptides ,Pharmaceutical Science ,Microbial Sensitivity Tests ,Review ,Conjugated system ,Antimicrobial ,Biodegradable polymer ,Combinatorial chemistry ,Analytical Chemistry ,lcsh:QD241-441 ,Anti-Infective Agents ,lcsh:Organic chemistry ,Chemistry (miscellaneous) ,peptides with antimicrobial activity ,biomedical polymers ,biodegradable polymers ,Drug Discovery ,Molecular Medicine ,Physical and Theoretical Chemistry ,Peptides ,polymeric carriers - Abstract
The past decade has seen growing interest in the investigation of peptides with antimicrobial activity (AMPs). One approach utilized in infection control is incorporation of antimicrobial agents conjugated with the polymers. This review presents the recent developments on polymeric AMP carriers and their potential applications in the biomedical and pharmaceutical fields.
- Published
- 2013
50. Application of Diethylzinc/Propyl Gallate Catalytic System for Ring-Opening Copolymerization of rac-Lactide and ε-Caprolactone.
- Author
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Wyrębiak, Rafał, Oledzka, Ewa, Figat, Ramona, and Sobczak, Marcin
- Subjects
- *
CLINICAL chemistry , *COPOLYMERIZATION , *RING-opening polymerization , *DIETHYLZINC , *MEDICAL polymers , *RING-opening reactions - Abstract
Biodegradable polyesters gain significant attention because of their wide potential biomedical applications. The ring-opening polymerization method is widely used to obtain such polymers, due to high yields and advantageous properties of the obtained material. The preparation of new, effective, and bio-safe catalytic systems for the synthesis of biomedical polymers is one of the main directions of the research in modern medical chemistry. The new diethylzinc/propyl gallate catalytic system was first used in the copolymerization of ε-caprolactone and rac-lactide. In this paper, the activity of the new zinc-based catalytic system in the copolymerization of cyclic esters depending on the reaction conditions was described. The microstructure analysis of the obtained copolyesters and their toxicity studies were performed. Resulted copolyesters were characterized by low toxicity, moderate dispersity (1.19–1.71), varying randomness degree (0.18–0.83), and average molar mass (5300–9800 Da). [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
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