Influence of Soft Segment Molecular Structure on Physicochemical Properties of Cellulose Nanocrystals based Polyurethane

Abstract SPUs are commonly used in clinic due to their good biocompatibility and can respond to different external stimuli. Among them, introducing CNCs into PUs to prepare water-driven PUs had attracted increasing attention. Herein, we report two new types of CNCs based PU nanocomposites by chemically cross-linking CNCs and PDLLA soft segment with flexible PEG chain or rigid piperazine ring structures. Specifically, the prepared nanocomposites were characterized by their morphology, chemical structure, thermal property, hydrophilicity as well as crystallinity, and the results showed that regardless of the molecular structure of the PDLLA, chemically cross-linking CNCs and PDLLA could significantly improve their compatibility. In addition, when the soft segment contains hydrophilic flexible sections, ie, PEG 200, the compatibility of CNCs with PU and crystallinity of obtained materials were better, and when the PDLLA contains a rigid cyclic structure, the thermal stability of obtained CNCs based PU would be more excellent. These results suggest that we can design the soft segment molecular structure of CNCs based PU to meet the performance requirements of different biomedical applications.

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Thermoresponsive Nanogels Based on Different Polymeric Moieties for Biomedical Applications

Gels ◽

10.3390/gels6030020 ◽

2020 ◽

Vol 6 (3) ◽

pp. 20 ◽

Cited By ~ 4

Author(s):

Sobhan Ghaeini-Hesaroeiye ◽

Hossein Razmi Bagtash ◽

Soheil Boddohi ◽

Ebrahim Vasheghani-Farahani ◽

Esmaiel Jabbari

Keyword(s):

Tissue Regeneration ◽

Targeted Delivery ◽

Biomedical Engineering ◽

Biomedical Applications ◽

Drug Delivery Systems ◽

Chemical Structure ◽

Salient Feature ◽

Clinical Applications ◽

Medical Applications ◽

External Stimuli

Nanogels, or nanostructured hydrogels, are one of the most interesting materials in biomedical engineering. Nanogels are widely used in medical applications, such as in cancer therapy, targeted delivery of proteins, genes and DNAs, and scaffolds in tissue regeneration. One salient feature of nanogels is their tunable responsiveness to external stimuli. In this review, thermosensitive nanogels are discussed, with a focus on moieties in their chemical structure which are responsible for thermosensitivity. These thermosensitive moieties can be classified into four groups, namely, polymers bearing amide groups, ether groups, vinyl ether groups and hydrophilic polymers bearing hydrophobic groups. These novel thermoresponsive nanogels provide effective drug delivery systems and tissue regeneration constructs for treating patients in many clinical applications, such as targeted, sustained and controlled release.

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Characterization of polydimethylsiloxane rubber upon photochemical, thermal, salt-fog ageings and exposure to acid vapours

e-Polymers ◽

10.1515/epoly.2006.6.1.172 ◽

2006 ◽

Vol 6 (1) ◽

Cited By ~ 2

Author(s):

F. Delor-Jestin ◽

N. S. Tomer ◽

R.P. Singh ◽

J. Lacoste

Keyword(s):

Ir Spectroscopy ◽

Chemical Structure ◽

Mesh Size ◽

Cross Linking ◽

Scanning Calorimetry ◽

New Knowledge ◽

Salt Fog ◽

Complementary Analysis ◽

Thermal Stability Of

AbstractThe changes in the chemical structure and the physical properties of a filled crosslinked polydimethylsiloxane rubber were monitored as a function of various ageing factors. The variables included photochemical, thermal, salt-fog ageings and exposure to acid vapours. Unaged and aged samples were studied by IR spectroscopy, hardness measurements, Differential Scanning Calorimetry (DSC) and thermogravimetric analysis (TGA) coupled with IR spectroscopy. No significant oxidation was detected after all ageings, except for nitric acid treatment. The presence of aluminium trihydrate was clearly identified as responsible for the observed chemical changes. Then an important vulnerability of this filled silicone rubber towards the cross-linking reactions provoked by usual ageings was also detected. The DSC-thermoporosimetry measurements of the mesh size distribution gave a comparison of cross-linking densities for each ageing. The complementary analysis with TGAIR allowed us to differenciate the thermal stability of the formulation after various ageings and to acquire new knowledge about thermal decomposition.

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Perfluoropolyether Modified Waterborne Shape Memory Polyurethaneurea Ionomers for Potential Medical Implant Application

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.499.53 ◽

2012 ◽

Vol 499 ◽

pp. 53-57

Author(s):

Qun Xia Li ◽

Zhong Yu Hou

Keyword(s):

Molecular Structure ◽

Differential Scanning Calorimetry ◽

Transition Temperature ◽

Shape Memory ◽

Soft Segment ◽

Cross Linking ◽

Isophorone Diisocyanate ◽

Scanning Calorimetry ◽

Weight Percentage ◽

Ft Ir

A series of cross-linked fluorinated waterborne shape memory polyurethaneurea (PUU) ionomers were synthesized from polycaprolactone diol, perfluoropolyether diol (PFPE), dimethylolproionic acid, isophorone diisocyanate, ethylenediamine (EDA) and diethylenetriamine (DETA). The effect of PFPE content in the soft segment and the degree of cross-linking on the molecular structure and the properties of for these PUU films was examined and studied. Differential scanning calorimetry showed that the transition temperature for these Tm type shape memory PUU could be facially tuned by PFPE weight percentage and EDA/DETA ratio in the range between 30°C to 50°C, in the vicinity of body temperature. The dependence of their properties on hydrogen-bonds evaluated by FT-IR was also discussed.

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Bio-Based Thermo-Reversible Aliphatic Polycarbonate Network

Molecules ◽

10.3390/molecules25010074 ◽

2019 ◽

Vol 25 (1) ◽

pp. 74 ◽

Cited By ~ 1

Author(s):

Pierre-Luc Durand ◽

Etienne Grau ◽

Henri Cramail

Keyword(s):

Thermal Stability ◽

Biomedical Applications ◽

Diels Alder ◽

Cross Linking ◽

Important Class ◽

Aliphatic Polycarbonate ◽

Biomedical Field ◽

The Cross ◽

Thermal Stability Of

Aliphatic polycarbonates represent an important class of materials with notable applications in the biomedical field. In this work, low Tg furan-functionalized bio-based aliphatic polycarbonates were cross-linked thanks to the Diels–Alder (DA) reaction with a bis-maleimide as the cross-linking agent. The thermo-reversible DA reaction allowed for the preparation of reversible cross-linked polycarbonate materials with tuneable properties as a function of the pendent furan content that was grafted on the polycarbonate backbone. The possibility to decrosslink the network around 70 °C could be an advantage for biomedical applications, despite the rather poor thermal stability of the furan-functionalized cross-linked polycarbonates.

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Review: Synthetic Polymer Hydrogels for Biomedical Applications

Chemistry & Chemical Technology ◽

10.23939/chcht04.04.297 ◽

2010 ◽

Vol 4 (4) ◽

pp. 297-304 ◽

Cited By ~ 7

Author(s):

Iwona Gibas ◽

◽

Helena Janik ◽

Keyword(s):

Water Uptake ◽

Biomedical Applications ◽

Chemical Structure ◽

Synthetic Polymer ◽

Cross Linking ◽

Polymer Hydrogels

Synthetic polymer hydrogels constitute a group of biomaterials, used in numerous biomedical disciplines, and are still developing for new promising applications. The aim of this study is to review information about well known and the newest hydrogels, show the importance of water uptake and cross-linking type and classify them in accordance with their chemical structure.

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Highly Tough, Biocompatible, and Magneto-Responsive Fe3O4/Laponite/PDMAAm Nanocomposite Hydrogels

Scientific Reports ◽

10.1038/s41598-019-51555-5 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Jin Hyun Lee ◽

Wen Jiao Han ◽

Hyo Seon Jang ◽

Hyoung Jin Choi

Keyword(s):

Mechanical Properties ◽

Biomedical Applications ◽

Chemical Structure ◽

Tensile Tests ◽

Thermal And Mechanical Properties ◽

Soft Actuator ◽

Nanocomposite Hydrogels ◽

Good Biocompatibility ◽

Responsive Hydrogels

Abstract Magneto-responsive hydrogels (MRHs) have attracted considerable attention in various applications owing to their smart response to an externally applied magnetic field. However, their practical uses in biomedical fields are limited by their weak mechanical properties and possible toxicity to the human body. In this study, tough, biocompatible, and magneto-responsive nanocomposite hydrogels (MR_NCHs) were developed by the in-situ free-radical polymerization of N, N-dimethylacrylamide (DMAAm) and laponite and Fe3O4 nanoparticles. The effects of the concentrations of DMAAm, water, and laponite and Fe3O4 nanoparticles in the pre-gel solutions or mixtures on the viscoelastic and mechanical properties of the corresponding hydrogels were examined by performing rheological and tensile tests, through which the mixture composition producing the best MR_NCH system was optimized. The effects were also explained by the possible network structures of the MR_NCHs. Moreover, the morphology, chemical structure, and thermal and mechanical properties of the MR_NCHs were analyzed, while comparing with those of the poly(DMAAm) (PDMAAm) hydrogels and laponite/PDMAAm NCHs. The obtained optimal MR_NCH exhibited noticeable magnetorheological (MR) behavior, excellent mechanical properties, and good biocompatibility. This study demonstrates how to optimize the best Fe3O4/laponite/PDMAAm MR_NCH system and its potential as a soft actuator for the pharmaceutical and biomedical applications.

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Demystifying and Unravelling the Factual Molecular Structure of the Biopolymer Sporopollenin

10.26434/chemrxiv.10059860.v1 ◽

2019 ◽

Author(s):

Abanoub Mikhael ◽

Kristina Jurcic ◽

Celine Schneider ◽

David carr ◽

Gregory L. Fisher ◽

...

Keyword(s):

Molecular Structure ◽

Biomedical Applications ◽

Chemical Structure ◽

Pollen Grains ◽

Outer Wall ◽

Mass Spectrometric ◽

Chemical Degradation ◽

Wastewater Purification ◽

Biochemical Pathways ◽

Micro Reactors

<p>Sporopollenin is a natural highly cross-linked biopolymer composed of carbon, hydrogen, and oxygen which forms the outer wall of pollen grains. Sporopollenin is resilient to chemical degradation. Because of this stability, its exact chemical structure and the biochemical pathways involved in its biosynthesis remains a mystery and unresolved.<sup> </sup>It is obvious that a well-conceived coherent study of the sporopollenin structure details will help immensely scientists in better understanding the chemistry of their current applications of sporopollenin exines such as drug delivery, peptide synthesis, micro-reactors, and wastewater purification. As well, it may also lead to the discovery of newer biomedical applications in the next coming years. We have identified and characterized the molecular structure of the clean, intact sporopollenin using mass spectrometric and nuclear magnetic resonance techniques. These analyses showed that sporopollenin is composed of a circular polyhydroxylated tetraketide polymer rigid backbone and a poly(hydroxyacid) branched network. The poly(hydroxyacid) network chains are attached by covalantly ether bonds to the polyhydroxylated tetraketides rigid backbone, forming the scaffold of the spherical sporopollenin.</p>

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How to Improve Physico-Chemical Properties of Silk Fibroin Materials for Biomedical Applications?—Blending and Cross-Linking of Silk Fibroin—A Review

Materials ◽

10.3390/ma14061510 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1510

Author(s):

Sylwia Grabska-Zielińska ◽

Alina Sionkowska

Keyword(s):

Silk Fibroin ◽

Biomedical Applications ◽

Magnetic Particles ◽

Chemical Properties ◽

Ternary Mixtures ◽

Cross Linking ◽

Advantages And Disadvantages ◽

Physico Chemical ◽

Binary And Ternary Mixtures ◽

To Receive

This review supplies a report on fresh advances in the field of silk fibroin (SF) biopolymer and its blends with biopolymers as new biomaterials. The review also includes a subsection about silk fibroin mixtures with synthetic polymers. Silk fibroin is commonly used to receive biomaterials. However, the materials based on pure polymer present low mechanical parameters, and high enzymatic degradation rate. These properties can be problematic for tissue engineering applications. An increased interest in two- and three-component mixtures and chemically cross-linked materials has been observed due to their improved physico-chemical properties. These materials can be attractive and desirable for both academic, and, industrial attention because they expose improvements in properties required in the biomedical field. The structure, forms, methods of preparation, and some physico-chemical properties of silk fibroin are discussed in this review. Detailed examples are also given from scientific reports and practical experiments. The most common biopolymers: collagen (Coll), chitosan (CTS), alginate (AL), and hyaluronic acid (HA) are discussed as components of silk fibroin-based mixtures. Examples of binary and ternary mixtures, composites with the addition of magnetic particles, hydroxyapatite or titanium dioxide are also included and given. Additionally, the advantages and disadvantages of chemical, physical, and enzymatic cross-linking were demonstrated.

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Thermo-responsive polymer encapsulated gold nanorods for single continuous wave laser-induced photodynamic/photothermal tumour therapy

Journal of Nanobiotechnology ◽

10.1186/s12951-020-00754-8 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Beilei Gong ◽

Yuanbing Shen ◽

Huiyan Li ◽

Xiaojun Li ◽

Xia Huan ◽

...

Keyword(s):

Gold Nanorods ◽

Biomedical Applications ◽

Continuous Wave ◽

Continuous Wave Laser ◽

Tumour Site ◽

Polymer Shell ◽

Potential System ◽

Responsive Polymer ◽

Good Biocompatibility ◽

Spr Effect

AbstractOwing to strong and tunable surface plasmon resonance (SPR) effect and good biocompatibility, gold nanoparticles have been suggested to be a versatile platform for a broad range of biomedical applications. In this study, a new nanoplatform of thermo-responsive polymer encapsulated gold nanorods incorporating indocyanine green (ICG) was designed to couple the photothermal properties of gold nanorods (AuNRs) and the photodynamic properties of ICG to enhance the photodynamic/photothermal combination therapy (PDT/PTT). In addition to the significantly increased payload and enhancing photostability of ICG, the polymer shell in the nanoplatform also has thermo-responsive characteristics that can control the release of drugs at tumour sites upon the laser irradiation. On the basis of these improvements, the nanoplatform strongly increased drug aggregation at the tumour site and improved the photothermal/photodynamic therapeutic efficacy. These results suggest that this nanoplatform would be a great potential system for tumour imaging and antitumour therapy.

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Graphene Integrated Hydrogels Based Biomaterials in Photothermal Biomedicine

Nanomaterials ◽

10.3390/nano11040906 ◽

2021 ◽

Vol 11 (4) ◽

pp. 906

Author(s):

Le Minh Tu Phan ◽

Thuy Anh Thu Vo ◽

Thi Xoan Hoang ◽

Sungbo Cho

Keyword(s):

Photothermal Therapy ◽

Biomedical Applications ◽

High Light ◽

Conversion Materials ◽

Potential Applications ◽

Good Biocompatibility ◽

Biomedical Field ◽

Hydrogel Composites ◽

Material Fabrication ◽

Biomedical Fields

Recently, photothermal therapy (PTT) has emerged as one of the most promising biomedical strategies for different areas in the biomedical field owing to its superior advantages, such as being noninvasive, target-specific and having fewer side effects. Graphene-based hydrogels (GGels), which have excellent mechanical and optical properties, high light-to-heat conversion efficiency and good biocompatibility, have been intensively exploited as potential photothermal conversion materials. This comprehensive review summarizes the current development of graphene-integrated hydrogel composites and their application in photothermal biomedicine. The latest advances in the synthesis strategies, unique properties and potential applications of photothermal-responsive GGel nanocomposites in biomedical fields are introduced in detail. This review aims to provide a better understanding of the current progress in GGel material fabrication, photothermal properties and potential PTT-based biomedical applications, thereby aiding in more research efforts to facilitate the further advancement of photothermal biomedicine.

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