Rapid in situ cross-linking of hydrogel adhesives based on thiol-grafted bio-inspired catechol-conjugated chitosan

In this paper, a novel chitosan derivative, thiol-grafting bio-inspired catechol-conjugated chitosan was synthesized. The chemical structure of the synthesized catechol-conjugated chitosan was verified by 1H NMR, and its contents of thiol group and catechol group were determined by UV-vis spectrum. Four percent of catechol-conjugated chitosan aqueous solution could form hydrogels rapidly in situ in 1 min or less with the addition of sodium periodate. Rheological studies showed that the mechanical properties depend on the concentrations of catechol-conjugated chitosan and the molar ratio of sodium periodate to catechol groups. Additionally, the adhesive properties of the resulting adhesives were evaluated, and the adhesion strength of obtained adhesives was as high as 50 kPa because of the complex and multiple interactions, especially the anti-oxidation mechanism of thiol group. The in vitro cytotoxicity assays demonstrated an excellent biocompatibility of the catechol-conjugated chitosan hydrogels. Benefiting from the in situ fast cured, desired mechanical strength, biocompatibility and relatively high adhesion performance, these properties suggested that catechol-conjugated chitosan hydrogel adhesives have potential applications as tissue adhesive for soft tissues.

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Ultra-strong bio-glue from genetically engineered polypeptides

Nature Communications ◽

10.1038/s41467-021-23117-9 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Chao Ma ◽

Jing Sun ◽

Bo Li ◽

Yang Feng ◽

Yao Sun ◽

...

Keyword(s):

Soft Tissues ◽

Covalent Bond ◽

Genetically Engineered ◽

Supramolecular Interactions ◽

Molar Ratio ◽

High Adhesion ◽

Strong Adhesion ◽

Order Of Magnitude

AbstractThe development of biomedical glues is an important, yet challenging task as seemingly mutually exclusive properties need to be combined in one material, i.e. strong adhesion and adaption to remodeling processes in healing tissue. Here, we report a biocompatible and biodegradable protein-based adhesive with high adhesion strengths. The maximum strength reaches 16.5 ± 2.2 MPa on hard substrates, which is comparable to that of commercial cyanoacrylate superglue and higher than other protein-based adhesives by at least one order of magnitude. Moreover, the strong adhesion on soft tissues qualifies the adhesive as biomedical glue outperforming some commercial products. Robust mechanical properties are realized without covalent bond formation during the adhesion process. A complex consisting of cationic supercharged polypeptides and anionic aromatic surfactants with lysine to surfactant molar ratio of 1:0.9 is driven by multiple supramolecular interactions enabling such strong adhesion. We demonstrate the glue’s robust performance in vitro and in vivo for cosmetic and hemostasis applications and accelerated wound healing by comparison to surgical wound closures.

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Quantification of assembly forces during creation of head-neck taper junction considering soft tissue bearing: a biomechanical study

Arthroplasty ◽

10.1186/s42836-021-00075-7 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Toni Wendler ◽

Torsten Prietzel ◽

Robert Möbius ◽

Jean-Pierre Fischer ◽

Andreas Roth ◽

...

Keyword(s):

Soft Tissue ◽

Work Experience ◽

Soft Tissues ◽

Force Sensor ◽

Biomechanical Study ◽

Measuring System ◽

Wide Range ◽

Head Neck

Abstract Background All current total hip arthroplasty (THA) systems are modular in design. Only during the operation femoral head and stem get connected by a Morse taper junction. The junction is realized by hammer blows from the surgeon. Decisive for the junction strength is the maximum force acting once in the direction of the neck axis, which is mainly influenced by the applied impulse and surrounding soft tissues. This leads to large differences in assembly forces between the surgeries. This study aimed to quantify the assembly forces of different surgeons under influence of surrounding soft tissue. Methods First, a measuring system, consisting of a prosthesis and a hammer, was developed. Both components are equipped with a piezoelectric force sensor. Initially, in situ experiments on human cadavers were carried out using this system in order to determine the actual assembly forces and to characterize the influence of human soft tissues. Afterwards, an in vitro model in the form of an artificial femur (Sawbones Europe AB, Malmo, Sweden) with implanted measuring stem embedded in gelatine was developed. The gelatine mixture was chosen in such a way that assembly forces applied to the model corresponded to those in situ. A study involving 31 surgeons was carried out on the aforementioned in vitro model, in which the assembly forces were determined. Results A model was developed, with the influence of human soft tissues being taken into account. The assembly forces measured on the in vitro model were, on average, 2037.2 N ± 724.9 N, ranging from 822.5 N to 3835.2 N. The comparison among the surgeons showed no significant differences in sex (P = 0.09), work experience (P = 0.71) and number of THAs performed per year (P = 0.69). Conclusions All measured assembly forces were below 4 kN, which is recommended in the literature. This could lead to increased corrosion following fretting in the head-neck interface. In addition, there was a very wide range of assembly forces among the surgeons, although other influencing factors such as different implant sizes or materials were not taken into account. To ensure optimal assembly force, the impaction should be standardized, e.g., by using an appropriate surgical instrument.

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Multifunctional Coatings for Robotic Implanted Device

International Journal of Molecular Sciences ◽

10.3390/ijms20205126 ◽

2019 ◽

Vol 20 (20) ◽

pp. 5126 ◽

Cited By ~ 2

Author(s):

Caterina Cristallini ◽

Serena Danti ◽

Bahareh Azimi ◽

Veronika Tempesti ◽

Claudio Ricci ◽

...

Keyword(s):

Acrylic Acid ◽

Vinyl Alcohol ◽

Soft Tissues ◽

Functional Characterization ◽

Titanium Substrate ◽

Repair Process ◽

Chemical Imaging ◽

In Vitro Cytotoxicity ◽

Poly Vinyl Alcohol

The objective of this study was the preparation and physico-chemical, mechanical, biological, and functional characterization of a multifunctional coating for an innovative, fully implantable device. The multifunctional coating was designed to have three fundamental properties: adhesion to device, close mechanical resemblance to human soft tissues, and control of the inflammatory response and tissue repair process. This aim was fulfilled by preparing a multilayered coating based on three components: a hydrophilic primer to allow device adhesion, a poly(vinyl alcohol) hydrogel layer to provide good mechanical compliance with the human tissue, and a layer of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) fibers. The use of biopolymer fibers offered the potential for a long-term interface able to modulate the release of an anti-inflammatory drug (dexamethasone), thus contrasting acute and chronic inflammation response following device implantation. Two copolymers, poly(vinyl acetate-acrylic acid) and poly(vinyl alcohol-acrylic acid), were synthetized and characterized using thermal analysis (DSC, TGA), Fourier transform infrared spectroscopy (FT-IR chemical imaging), in vitro cell viability, and an adhesion test. The resulting hydrogels were biocompatible, biostable, mechanically compatible with soft tissues, and able to incorporate and release the drug. Finally, the multifunctional coating showed a good adhesion to titanium substrate, no in vitro cytotoxicity, and a prolonged and controlled drug release.

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Study on Bone Cell Adaptability of α-TCP/HAp Functionally Graded Porous Beads for Biomaterials Application

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.76.143 ◽

2010 ◽

Vol 76 ◽

pp. 143-146

Author(s):

S. Ohtake ◽

T. Asaoka ◽

K. Furukawa ◽

T. Ushida ◽

T. Tateishi

Keyword(s):

Bone Cells ◽

High Strength ◽

Bone Cell ◽

Functionally Graded ◽

The Body ◽

Tissue Adhesive ◽

Adhesive Properties ◽

Living Body ◽

Porous Beads

Porous beads of bioactive ceramics such as HAp, TCP are considered to be promising as excellent scaffolds for cultivating bone cells. To realize this type of beads which maintains the function of scaffold with sufficient strength up to growth of new bone, and is expected to absorbed completely after the growth, a-TCP/ HAp functionally graded porous beads were fabricated. HAp is bioactive material which has both high strength and better tissue-adhesive properties, but that is not readily absorbed by the human body. On the contrary, a-TCP is highly bioabsorbable; it is quickly absorbed by the body, and, therefore, disappears before bone is completely replaced. Fabricated new beads are composed of a-TCP at the center and HAp at the surface, to control the solubility in living body. Bone cell adaptability of these beads were confirmed in vitro.

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Concomitant release of sialic acids and calcium by neuraminidase from rat aorta in situ

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1988.0068 ◽

1988 ◽

Vol 235 (1279) ◽

pp. 139-144 ◽

Cited By ~ 2

Keyword(s):

Sialic Acid ◽

Wistar Rats ◽

Rat Aorta ◽

Sialic Acids ◽

Molar Ratio ◽

Male Wistar Rats

Male Wistar rats were heparinized and killed with pentobarbital. The upper and lower ends of the aortae were cannulated and the blood was washed out with saline until the washings contained calcium and sialic-acid-reacting material at minimal concentrations. The aortae were perfused with neuraminidase for 15 min. This caused the appearance of calcium as well as of sialic acids in the perfusate in total amounts of about 5.3 nmol and about 3.6 nmol per aorta respectively. The molar ratio of about 1.5 is sufficiently close to that determined for the association of calcium with sialic acids in vitro to suggest that their association is similar in vivo .

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Injectable in situ forming drug delivery system for cancer chemotherapy using a novel tissue adhesive: Characterization and in vitro evaluation

European Journal of Pharmaceutics and Biopharmaceutics ◽

10.1016/j.ejpb.2006.11.022 ◽

2007 ◽

Vol 66 (3) ◽

pp. 383-390 ◽

Cited By ~ 32

Author(s):

Sachiro Kakinoki ◽

Tetsushi Taguchi ◽

Hirofumi Saito ◽

Junzo Tanaka ◽

Tetsuya Tateishi

Keyword(s):

Drug Delivery ◽

Drug Delivery System ◽

Delivery System ◽

Cancer Chemotherapy ◽

Tissue Adhesive ◽

In Vitro Evaluation ◽

In Situ Forming

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In Vitro Evaluation of an Implantable Force Transducer (IFT) in a Patellar Tendon Model

Journal of Biomechanical Engineering ◽

10.1115/1.2895495 ◽

1993 ◽

Vol 115 (4A) ◽

pp. 335-343 ◽

Cited By ~ 32

Author(s):

D. L. Glos ◽

D. L. Butler ◽

E. S. Grood ◽

M. S. Levy

Keyword(s):

Patellar Tendon ◽

Measurement Errors ◽

Soft Tissues ◽

Force Transducer ◽

Device Performance ◽

Test Results ◽

Transducer Design ◽

Model Device

A new implantable transducer has been developed for in situ evaluation of ligament and tendon forces. Unlike previous devices, this sensor is placed within the specimen, minimizing measurement errors due to impingement on surrounding soft tissues and bone. In this study, we present the sensor design details as well as test results from initial in vitro trials in the goat patellar tendon model. Device performance and influence of the device on the specimen were evaluated under several loading conditions. In all cases, device output had a strong correlation with induced tissue load. Significant variations in device performance were only noted at high tissue deformation rates. More extensive investigations will be conducted to assess how changes in transducer design might alter performance characteristics.

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In Vitro and In Vivo Biocompatibility of Nano-Hydroxyapatite/Collagen Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.288-289.195 ◽

2005 ◽

Vol 288-289 ◽

pp. 195-198

Author(s):

Xiao Yan Lin ◽

Hong Song Fan ◽

Xu Dong Li ◽

Min Tang ◽

Ling Li Zhang ◽

...

Keyword(s):

Mutagenic Activity ◽

Calcium Nitrate ◽

In Vitro Cytotoxicity ◽

Cytotoxicity Test ◽

Hydrogen Phosphate ◽

Diffusion Test ◽

Micronucleus Tests

A nano-grade hydroxyapatite/collagen composite was prepared by an in situ synthesis technique from calcium nitrate, diammoniun hydrogen phosphate, and a cowhide collagen sol at low temperature. XRD and TEM analyses of the composite indicated that crystals formed in the collagen fibril matrix were nanohydroxyapatite with low crystallinity. Biocompatibility of the composite was evaluated by in vitro cytotoxicity test and in vivo genotoxicity and sensitization test. No mutagenic activity of the composite was observed in mouse micronucleus tests. No evidence of dermal sensitization of the composite was found in guinea pig maximization tests. The results from a filter diffusion test indicated that the composite did not induce a cytotoxic behavior. All these results suggest that the composite has excellent biocompatibility.

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