Layer-by-Layer Fabrication of 3D Hydrogel Structures Using Open Microfluidics

Patterning and 3D fabrication techniques have enabled the use of hydrogels for a number of applications including microfluidics, sensors, separations, and tissue engineering in which form fits function. Devices such as reconfigurable microvalves or implantable tissues have been created using lithography or casting techniques. Here, we present a novel open microfluidic patterning method that utilizes surface tension forces to pattern hydrogel layers on top of each other, producing 3D hydrogel structures. We use a patterning device to form a temporary open microfluidic channel on an existing gel layer, allowing the controlled flow of unpolymerized gel in regions defined by the device. Once the gel is polymerized, the patterning device can then be removed, and subsequent layers added to create a multi-layered 3D structure. The use of open-microfluidic and surface tension-based methods to define the shape of each layer enables patterning to be performed with a simple pipette, minimizing dead-volume and shear stress applied on the fluid. Our method is compatible with unmodified (native) biological hydrogels, or other non-biological materials with fluid properties compatible with capillary flow. With our open-microfluidic layer-by-layer fabrication method, we demonstrate the capability to build agarose and type I collagen structures featuring asymmetric designs, multiple components, overhanging features, and cell laden regions.

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On-Chip Fabrication of None-Dead-Volume Microtips for ESI-MS Applications

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.121-123.611 ◽

2007 ◽

Vol 121-123 ◽

pp. 611-614

Author(s):

Che Hsin Lin ◽

Jen Taie Shiea ◽

Yen Lieng Lin

Keyword(s):

Surface Tension ◽

Low Cost ◽

Microfluidic Channel ◽

Dead Volume ◽

Esi Ms ◽

Rapid Fabrication ◽

Chip Fabrication ◽

Novel Method ◽

On Chip ◽

Highly Uniform

This paper proposes a novel method to on-chip fabricate a none-dead-volume microtip for ESI-MS applications. The microfluidic chip and ESI tip are fabricated in low-cost plastic based materials using a simple and rapid fabrication process. A constant-speed-pulling method is developed to fabricate the ESI tip by pulling mixed PMMA glue using a 30-μm stainless wire through the pre-formed microfluidic channel. The equilibrium of surface tension of PMMA glue will result in a sharp tip after curing. A highly uniform micro-tip can be formed directly at the outlet of the microfluidic channel with minimum dead-volume zone. Detection of caffeine, myoglobin, lysozyme and cytochrome C biosamples confirms the microchip device can be used for high resolution ESI-MS applications.

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Effect of temperature on surface tension and surface dilational rheology of type I collagen

Colloids and Surfaces A Physicochemical and Engineering Aspects ◽

10.1016/j.colsurfa.2014.05.025 ◽

2014 ◽

Vol 460 ◽

pp. 168-175 ◽

Cited By ~ 8

Author(s):

Aleksandra Kezwon ◽

Kamil Wojciechowski

Keyword(s):

Surface Tension ◽

Type I Collagen ◽

Effect Of Temperature ◽

Type I ◽

Dilational Rheology

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Layer-by-layer assembly of type I collagen and chondroitin sulfate on aminolyzed PU for potential cartilage tissue engineering application

Applied Surface Science ◽

10.1016/j.apsusc.2012.06.051 ◽

2012 ◽

Vol 258 (24) ◽

pp. 9918-9925 ◽

Cited By ~ 24

Author(s):

Xianyun He ◽

Yingjun Wang ◽

Gang Wu

Keyword(s):

Tissue Engineering ◽

Chondroitin Sulfate ◽

Type I Collagen ◽

Cartilage Tissue Engineering ◽

Engineering Application ◽

Cartilage Tissue ◽

Tissue Engineering Application ◽

Type I ◽

Layer By Layer ◽

Layer Assembly

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Bioengineering Approaches to Improve In Vitro Performance of Prepubertal Lamb Oocytes

Cells ◽

10.3390/cells10061458 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1458

Author(s):

Antonella Mastrorocco ◽

Ludovica Cacopardo ◽

Daniela Lamanna ◽

Letizia Temerario ◽

Giacomina Brunetti ◽

...

Keyword(s):

Oocyte Maturation ◽

Large Scale ◽

Type I Collagen ◽

3D Structure ◽

Three Dimensional ◽

Basal Membrane ◽

Type I ◽

Animal Reproduction ◽

Blastocyst Quality

Juvenile in vitro embryo technology (JIVET) provides exciting opportunities in animal reproduction by reducing the generation intervals. Prepubertal oocytes are also relevant models for studies on oncofertility. However, current JIVET efficiency is still unpredictable, and further improvements are needed in order for it to be used on a large-scale level. This study applied bioengineering approaches to recreate: (1) the three-dimensional (3D) structure of the cumulus–oocyte complex (COC), by constructing—via bioprinting technologies—alginate-based microbeads (COC-microbeads) for 3D in vitro maturation (3D-IVM); (2) dynamic IVM conditions, by culturing the COC in a millifluidic bioreactor; and (3) an artificial follicular wall with basal membrane, by adding granulosa cells (GCs) and type I collagen (CI) during bioprinting. The results show that oocyte nuclear and cytoplasmic maturation, as well as blastocyst quality, were improved after 3D-IVM compared to 2D controls. The dynamic 3D-IVM did not enhance oocyte maturation, but it improved oocyte bioenergetics compared with static 3D-IVM. The computational model showed higher oxygen levels in the bioreactor with respect to the static well. Microbead enrichment with GCs and CI improved oocyte maturation and bioenergetics. In conclusion, this study demonstrated that bioengineering approaches that mimic the physiological follicle structure could be valuable tools to improve IVM and JIVET.

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Evaluation of the Grafting Efficacy of Active Biomolecules of Phosphatidylcholine and Type I Collagen on Polyether Ether Ketone: In Vitro and In Vivo

Polymers ◽

10.3390/polym13132081 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2081

Author(s):

Jian-Chih Chen ◽

Chih-Hua Chen ◽

Kai-Chi Chang ◽

Shih-Ming Liu ◽

Chia-Ling Ko ◽

...

Keyword(s):

Type I Collagen ◽

3D Structure ◽

Orthopedic Implants ◽

Type I ◽

Polyether Ether Ketone ◽

Hydrophilic Nature ◽

Potential Alternative ◽

Ether Ketone

Biomolecule grafting on polyether ether ketone (PEEK) was used to improve cell affinity caused by surface inertness. This study demonstrated the sequence-polished (P) and sulfonated (SA) PEEK modification to make a 3D structure, active biomolecule graftings through PEEK silylation (SA/SI) and then processed with phosphatidylcholine (with silylation of SA/SI/PC; without SA/PC) and type I collagen (COL I, with silylation of SA/SI/C; without SA/C). Different modified PEEKs were implanted for 4, 8, and 12 weeks for histology. Sulfonated PEEK of SA showed the surface roughness was significantly increased; after the silylation of SA/SI, the hydrophilic nature was remarkably improved. The biomolecules were effectively grafted through silylation, and the cells showed improved attachment after 1 h. Furthermore, the SA/SI/PC group showed good in vitro mineralization. The new bone tissues were integrated into the 3D porous structures of SA/SI/PC and SA/SI/C in vivo making PEEK a potential alternative to metals in orthopedic implants.

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Nonuniformity in Periodontal Ligament: Mechanics and Matrix Composition

Journal of Dental Research ◽

10.1177/0022034520962455 ◽

2020 ◽

pp. 002203452096245

Author(s):

B.K. Connizzo ◽

L. Sun ◽

N. Lacin ◽

A. Gendelman ◽

I. Solomonov ◽

...

Keyword(s):

Periodontal Ligament ◽

Type I Collagen ◽

Alveolar Bone ◽

Tooth Movement ◽

Critical Role ◽

3D Structure ◽

Matrix Composition ◽

Type I ◽

Critical Function ◽

Significant Difference

The periodontal ligament (PDL) plays a critical role in providing immediate response to abrupt high loads during mastication while also facilitating slow remodeling of the alveolar bone. The PDL exceptional functionality is permitted by the unique nonuniform structure of the tissue. Two distinct areas that are critical to PDL function were previously identified: the furcation and the dense collar. Despite their hypothesized functions in tooth movement and maintenance, these 2 regions have not yet been compared within the context of their native environment. Therefore, the objective of this study is to elucidate the extracellular matrix (ECM) structure, composition, and biomechanical function of the furcation and the collar regions while maintaining the 3-dimensional (3D) structure in the murine PDL. We identify significant difference between the collar and furcation regions in both structure and mechanical properties. Specifically, we observed unique longitudinal structures in the dense collar that correlate with type VI collagen and LOX, both of which are associated with increased type I collagen density and tissue stiffness and are therefore proposed to function as scaffolds for tooth stabilization. We also found that the collar region is stiffer than the furcation region and therefore suggest that the dense collar acts as a suspense structure of the tooth within the bone during physiological loading. The furcation region of the PDL contained more proteins associated with reduced stiffness and higher tissue remodeling, as well as a dual mechanical behavior, suggesting a critical function in loads transfer and remodeling of the alveolar bone. In summary, this work unravels the nonuniform nature of the PDL within the 3D structural context and establishes understanding of regional PDL function, which opens new avenues for future studies of remodeling, regeneration, and disease.

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Reducing the Foreign Body Reaction by Surface Modification with Collagen/Hyaluronic Acid Multilayered Films

ISRN Biomaterials ◽

10.1155/2014/718432 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 8

Author(s):

Cindy Yi Chi Hsieh ◽

Fang-Wei Hu ◽

Wen-Shiang Chen ◽

Wei-Bor Tsai

Keyword(s):

Surface Modification ◽

Hyaluronic Acid ◽

Foreign Body ◽

Type I Collagen ◽

Foreign Body Reaction ◽

Biological Response ◽

Multilayer Films ◽

Type I ◽

Layer By Layer

Biological response against foreign implants often leads to encapsulation, possibly resulting in malfunction of implants devices. The aim of this study was to reduce the foreign body reaction by surface modification of biomaterials through layer-by-layer deposition of type I collagen (COL)/hyaluronic acid (HA) multilayer films. Polydimethylsiloxane (PDMS) samples were coated with alternative COL and HA layers with different layers. We found that the in vitro adhesion, proliferation, and activation of macrophage-like cells were greatly decreased by COL/HA multilayered deposition. The PDMS samples modified with 20 bilayers of COL/HA were implanted in rats for 3 weeks, and the thickness of encapsulation surrounding the samples was decreased by 29–57% compared to the control unmodified PDMS. This study demonstrates the potential of COL/HA multilayer films to reduce foreign body reaction.

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Collagen fibrillogenesis in vitro: interaction of types I and V collagen

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142670 ◽

1986 ◽

Vol 44 ◽

pp. 210-211

Author(s):

Arthur J. Wasserman ◽

Kathy C. Kloos ◽

David E. Birk

Keyword(s):

Type I Collagen ◽

Corneal Stroma ◽

Minor Component ◽

Homogeneous Distribution ◽

Type I ◽

Type V Collagen ◽

Fibril Morphology ◽

Type V ◽

In Vitro Interaction

Type I collagen is the predominant collagen in the cornea with type V collagen being a quantitatively minor component. However, the content of type V collagen (10-20%) in the cornea is high when compared to other tissues containing predominantly type I collagen. The corneal stroma has a homogeneous distribution of these two collagens, however, immunochemical localization of type V collagen requires the disruption of type I collagen structure. This indicates that these collagens may be arranged as heterpolymeric fibrils. This arrangement may be responsible for the control of fibril diameter necessary for corneal transparency. The purpose of this work is to study the in vitro assembly of collagen type V and to determine whether the interactions of these collagens influence fibril morphology.

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