Origin of transparency in scattering biomimetic collagen materials

Living tissues, heterogeneous at the microscale, usually scatter light. Strong scattering is responsible for the whiteness of bones, teeth, and brain and is known to limit severely the performances of biomedical optical imaging. Transparency is also found within collagen-based extracellular tissues such as decalcified ivory, fish scales, or cornea. However, its physical origin is still poorly understood. Here, we unveil the presence of a gap of transparency in scattering fibrillar collagen matrices within a narrow range of concentration in the phase diagram. This precholesteric phase presents a three-dimensional (3D) orientational order biomimetic of that in natural tissues. By quantitatively studying the relation between the 3D fibrillar network and the optical and mechanical properties of the macroscopic matrices, we show that transparency results from structural partial order inhibiting light scattering, while preserving mechanical stability, stiffness, and nonlinearity. The striking similarities between synthetic and natural materials provide insights for better understanding the occurring transparency.

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MECHANICAL BEHAVIOR UNDER UNCONFINED COMPRESSION LOADINGS OF DENSE FIBRILLAR COLLAGEN MATRICES MIMETIC OF LIVING TISSUES

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519410003290 ◽

2010 ◽

Vol 10 (01) ◽

pp. 35-55 ◽

Cited By ~ 12

Author(s):

SALAH RAMTANI ◽

YOSHIYUKI TAKAHASHI-IÑIGUEZ ◽

CHRISTOPHE HELARY ◽

DIDIER GEIGER ◽

MARIE MADELEINE GIRAUD GUILLE

Keyword(s):

Mechanical Properties ◽

Soft Tissues ◽

Three Dimensional ◽

Fibrillar Collagen ◽

Unconfined Compression ◽

Collagen Scaffolds ◽

Collagen Concentration ◽

Collagen Matrices ◽

Compression Load ◽

Living Tissues

Bio-artificial tissues are being developed as replacements for damaged biologic tissues and their mechanical properties are critical for load-bearing applications. Reconstituted dense three-dimensional (3D) fibrillar collagen matrices are promising materials for tissue engineering, at the light of their interaction with fibroblasts.1,2 The mechanical properties of these fibrillar collagen matrices are now being characterized under unconfined compression loading for various strain rates and collagen concentrations. The data were compared to those obtained in the same conditions with a biological tissue, the rat dermis. The results show a very sensitive behavior to both the displacement rate, typical of biological soft tissues, and the collagen concentration varying between 5 and 40 mg/ml. The link between the mechanical properties and the microscopic structure of the collagen scaffolds show an increasing viscoelastic modulus with respect to the fibril density. It is found that the matrices at 5 mg/ml and the dorsal rat skin (DRS) exhibit similar stress–strain response when submitted to the same external unconfined compression load. Such results highlight the interest of these matrices as potential tissue substitutes.

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Molecular mechanisms of tumor invasion in three-dimensional collagen matrices

10.32469/10355/6016 ◽

2007 ◽

Author(s):

Kevin E. Fisher

Keyword(s):

Tumor Invasion ◽

Molecular Mechanisms ◽

Three Dimensional ◽

Collagen Matrices

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Mechanical Behavior of Hydroxyapatite-Chitosan Composite: Effect of Processing Parameters

Minerals ◽

10.3390/min11020213 ◽

2021 ◽

Vol 11 (2) ◽

pp. 213

Author(s):

Hamid Ait Said ◽

Hassan Noukrati ◽

Hicham Ben Youcef ◽

Ayoub Bayoussef ◽

Hassane Oudadesse ◽

...

Keyword(s):

Molecular Weight ◽

Compressive Strength ◽

Mechanical Strength ◽

Bone Repair ◽

Mechanical Stability ◽

Three Dimensional ◽

Processing Parameters ◽

Composite Effect ◽

Solid Liquid ◽

The Impact

Three-dimensional hydroxyapatite-chitosan (HA-CS) composites were formulated via solid-liquid technic and freeze-drying. The prepared composites had an apatitic nature, which was demonstrated by X-ray diffraction and Infrared spectroscopy analyses. The impact of the solid/liquid (S/L) ratio and the content and the molecular weight of the polymer on the composite mechanical strength was investigated. An increase in the S/L ratio from 0.5 to 1 resulted in an increase in the compressive strength for HA-CSL (CS low molecular weight: CSL) from 0.08 ± 0.02 to 1.95 ± 0.39 MPa and from 0.3 ± 0.06 to 2.40 ± 0.51 MPa for the HA-CSM (CS medium molecular weight: CSM). Moreover, the increase in the amount (1 to 5 wt%) and the molecular weight of the polymer increased the mechanical strength of the composite. The highest compressive strength value (up to 2.40 ± 0.51 MPa) was obtained for HA-CSM (5 wt% of CS) formulated at an S/L of 1. The dissolution tests of the HA-CS composites confirmed their cohesion and mechanical stability in an aqueous solution. Both polymer and apatite are assumed to work together, giving the synergism needed to make effective cylindrical composites, and could serve as a promising candidate for bone repair in the orthopedic field.

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Comparative Study of Silk Fibroin-Based Hydrogels and Their Potential as Material for 3-Dimensional (3D) Printing

Molecules ◽

10.3390/molecules26133887 ◽

2021 ◽

Vol 26 (13) ◽

pp. 3887

Author(s):

Watcharapong Pudkon ◽

Chavee Laomeephol ◽

Siriporn Damrongsakkul ◽

Sorada Kanokpanont ◽

Juthamas Ratanavaraporn

Keyword(s):

3D Printing ◽

Silk Fibroin ◽

Biomedical Applications ◽

Mechanical Stability ◽

Three Dimensional ◽

Structure Stability ◽

3 Dimensional ◽

Critical Technology ◽

Box Structure ◽

High Degree

Three-dimensional (3D) printing is regarded as a critical technology in material engineering for biomedical applications. From a previous report, silk fibroin (SF) has been used as a biomaterial for tissue engineering due to its biocompatibility, biodegradability, non-toxicity and robust mechanical properties which provide a potential as material for 3D-printing. In this study, SF-based hydrogels with different formulations and SF concentrations (1–3%wt) were prepared by natural gelation (SF/self-gelled), sodium tetradecyl sulfate-induced (SF/STS) and dimyristoyl glycerophosphorylglycerol-induced (SF/DMPG). From the results, 2%wt SF-based (2SF) hydrogels showed suitable properties for extrusion, such as storage modulus, shear-thinning behavior and degree of structure recovery. The 4-layer box structure of all 2SF-based hydrogel formulations could be printed without structural collapse. In addition, the mechanical stability of printed structures after three-step post-treatment was investigated. The printed structure of 2SF/STS and 2SF/DMPG hydrogels exhibited high stability with high degree of structure recovery as 70.4% and 53.7%, respectively, compared to 2SF/self-gelled construct as 38.9%. The 2SF/STS and 2SF/DMPG hydrogels showed a great potential to use as material for 3D-printing due to its rheological properties, printability and structure stability.

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Dendritic Fibroblasts in Three-dimensional Collagen Matrices

Molecular Biology of the Cell ◽

10.1091/mbc.e02-08-0493 ◽

2003 ◽

Vol 14 (2) ◽

pp. 384-395 ◽

Cited By ~ 139

Author(s):

Frederick Grinnell ◽

Chin-Han Ho ◽

Elisa Tamariz ◽

David J. Lee ◽

Gabriella Skuta

Keyword(s):

Dimensional Space ◽

Human Fibroblasts ◽

Three Dimensional ◽

Rho Kinase ◽

Matrix Remodeling ◽

Dependent Manner ◽

Collagen Matrices ◽

Form And Function ◽

Metabolic Coupling ◽

Dendritic Network

Cell motility determines form and function of multicellular organisms. Most studies on fibroblast motility have been carried out using cells on the surfaces of culture dishes. In situ, however, the environment for fibroblasts is the three-dimensional extracellular matrix. In the current research, we studied the morphology and motility of human fibroblasts embedded in floating collagen matrices at a cell density below that required for global matrix remodeling (i.e., contraction). Under these conditions, cells were observed to project and retract a dendritic network of extensions. These extensions contained microtubule cores with actin concentrated at the tips resembling growth cones. Platelet-derived growth factor promoted formation of the network; lysophosphatidic acid stimulated its retraction in a Rho and Rho kinase-dependent manner. The dendritic network also supported metabolic coupling between cells. We suggest that the dendritic network provides a mechanism by which fibroblasts explore and become interconnected to each other in three-dimensional space.

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Direct coherent multi-ink printing of fabric supercapacitors

Science Advances ◽

10.1126/sciadv.abd6978 ◽

2021 ◽

Vol 7 (3) ◽

pp. eabd6978 ◽

Cited By ~ 1

Author(s):

Jingxin Zhao ◽

Hongyu Lu ◽

Yan Zhang ◽

Shixiong Yu ◽

Oleksandr I. Malyi ◽

...

Keyword(s):

System Integration ◽

High Performance ◽

Mechanical Stability ◽

Three Dimensional ◽

High Mass ◽

Wearable Electronics ◽

Energy Storage Devices ◽

Fabrication Procedure ◽

Self Powered ◽

Mechanical Devices

Coaxial fiber-shaped supercapacitors with short charge carrier diffusion paths are highly desirable as high-performance energy storage devices for wearable electronics. However, the traditional approaches based on the multistep fabrication processes for constructing the fiber-shaped energy device still encounter persistent restrictions in fabrication procedure, scalability, and mechanical durability. To overcome this critical challenge, an all-in-one coaxial fiber-shaped asymmetric supercapacitor (FASC) device is realized by a direct coherent multi-ink writing three-dimensional printing technology via designing the internal structure of the coaxial needles and regulating the rheological property and the feed rates of the multi-ink. Benefitting from the compact coaxial structure, the FASC device delivers a superior areal energy/power density at a high mass loading, and outstanding mechanical stability. As a conceptual exhibition for system integration, the FASC device is integrated with mechanical units and pressure sensor to realize high-performance self-powered mechanical devices and monitoring systems, respectively.

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Current Update of Collagen Nanomaterials—Fabrication, Characterisation and Its Applications: A Review

Pharmaceutics ◽

10.3390/pharmaceutics13030316 ◽

2021 ◽

Vol 13 (3) ◽

pp. 316

Author(s):

Samantha Lo ◽

Mh Busra Fauzi

Keyword(s):

Mechanical Stability ◽

Health Management ◽

Three Dimensional ◽

Volume Ratio ◽

Cartilage Regeneration ◽

Nerve Tissue ◽

Electrospinning Technique ◽

Engineering Technology ◽

Promising Alternative ◽

Tissue Repair And Regeneration

Tissue engineering technology is a promising alternative approach for improvement in health management. Biomaterials play a major role, acting as a provisional bioscaffold for tissue repair and regeneration. Collagen a widely studied natural component largely present in the extracellular matrix (ECM) of the human body. It provides mechanical stability with suitable elasticity and strength to various tissues, including skin, bone, tendon, cornea and others. Even though exogenous collagen is commonly used in bioscaffolds, largely in the medical and pharmaceutical fields, nano collagen is a relatively new material involved in nanotechnology with a plethora of unexplored potential. Nano collagen is a form of collagen reduced to a nanoparticulate size, which has its advantages over the common three-dimensional (3D) collagen design, primarily due to its nano-size contributing to a higher surface area-to-volume ratio, aiding in withstanding large loads with minimal tension. It can be produced through different approaches including the electrospinning technique to produce nano collagen fibres resembling natural ECM. Nano collagen can be applied in various medical fields involving bioscaffold insertion or fillers for wound healing improvement; skin, bone, vascular grafting, nerve tissue and articular cartilage regeneration as well as aiding in drug delivery and incorporation for cosmetic purposes.

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The differential regulation of cell motile activity through matrix stiffness and porosity in three dimensional collagen matrices

Biomaterials ◽

10.1016/j.biomaterials.2010.04.064 ◽

2010 ◽

Vol 31 (25) ◽

pp. 6425-6435 ◽

Cited By ~ 144

Author(s):

Miguel Miron-Mendoza ◽

Joachim Seemann ◽

Frederick Grinnell

Keyword(s):

Three Dimensional ◽

Differential Regulation ◽

Matrix Stiffness ◽

Collagen Matrices ◽

Motile Activity

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Apolar and polar transitions drive the conversion between amoeboid and mesenchymal shapes in melanoma cells

Molecular Biology of the Cell ◽

10.1091/mbc.e15-06-0382 ◽

2015 ◽

Vol 26 (22) ◽

pp. 4163-4170 ◽

Cited By ~ 17

Author(s):

Sam Cooper ◽

Amine Sadok ◽

Vicky Bousgouni ◽

Chris Bakal

Keyword(s):

Quantitative Imaging ◽

Three Dimensional ◽

Shape Space ◽

Melanoma Cells ◽

Collagen Matrices ◽

Morphological Heterogeneity ◽

Rho Family Gtpases ◽

Metastatic Process ◽

Rho Family ◽

Single Living

Melanoma cells can adopt two functionally distinct forms, amoeboid and mesenchymal, which facilitates their ability to invade and colonize diverse environments during the metastatic process. Using quantitative imaging of single living tumor cells invading three-dimensional collagen matrices, in tandem with unsupervised computational analysis, we found that melanoma cells can switch between amoeboid and mesenchymal forms via two different routes in shape space—an apolar and polar route. We show that whereas particular Rho-family GTPases are required for the morphogenesis of amoeboid and mesenchymal forms, others are required for transitions via the apolar or polar route and not amoeboid or mesenchymal morphogenesis per se. Altering the transition rates between particular routes by depleting Rho-family GTPases can change the morphological heterogeneity of cell populations. The apolar and polar routes may have evolved in order to facilitate conversion between amoeboid and mesenchymal forms, as cells are either searching for, or attracted to, particular migratory cues, respectively.

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