scholarly journals Facile Cell-Friendly Hollow-Core Fiber Diffusion-Limited Photofabrication

2021 ◽  
Vol 9 ◽  
Author(s):  
Alexander G. Savelyev ◽  
Anastasia V. Sochilina ◽  
Roman A. Akasov ◽  
Anton V. Mironov ◽  
Alina Yu. Kapitannikova ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Free Radicals ◽  
Three Dimensional ◽  
Single Step ◽  
Flavin Mononucleotide ◽  
Outer Diameter ◽  
Solid Core ◽  
Hollow Core ◽  
Fabrication Procedure ◽  
Core Fiber

Bioprinting emerges as a powerful flexible approach for tissue engineering with prospective capability to produce tissue on demand, including biomimetic hollow-core fiber structures. In spite of significance for tissue engineering, hollow-core structures proved difficult to fabricate, with the existing methods limited to multistage, time-consuming, and cumbersome procedures. Here, we report a versatile cell-friendly photopolymerization approach that enables single-step prototyping of hollow-core as well as solid-core hydrogel fibers initially loaded with living cells. This approach was implemented by extruding cell-laden hyaluronic acid glycidyl methacrylate hydrogel directly into aqueous solution containing free radicals generated by continuous blue light photoexcitation of the flavin mononucleotide/triethanolamine photoinitiator. Diffusion of free radicals from the solution to the extruded structure initiated cross-linking of the hydrogel, progressing from the structure surface inwards. Thus, the cross-linked wall is formed and its thickness is limited by penetration of free radicals in the hydrogel volume. After developing in water, the hollow-core fiber is formed with centimeter range of lengths. Amazingly, HaCaT cells embedded in the hydrogel successfully go through the fabrication procedure. The broad size ranges have been demonstrated: from solid core to 6% wall thickness of the outer diameter, which was variable from sub-millimeter to 6 mm, and Young’s modulus ∼1.6 ± 0.4 MPa. This new proof-of-concept fibers photofabrication approach opens lucrative opportunities for facile three-dimensional fabrication of hollow-core biostructures with controllable geometry.

scholarly journals Microfluidic Raman Sensing Using a Single Ring Negative Curvature Hollow Core Fiber

Biosensors ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 430
Author(s):  
Xinyu Wang ◽  
Shuguang Li ◽  
Shoufei Gao ◽  
Yingying Wang ◽  
Pu Wang ◽  
...  
Keyword(s):  
Negative Curvature ◽  
Limit Of Detection ◽  
Detection System ◽  
Low Cost ◽  
Coupling Efficiency ◽  
Solid Core ◽  
Hollow Core ◽  
Single Ring ◽  
Excitation Laser ◽  
Core Fiber

A compact microfluidic Raman detection system based on a single-ring negative-curvature hollow-core fiber is presented. The system can be used for in-line qualitative and quantitative analysis of biochemicals. Both efficient light coupling and continuous liquid injection into the hollow-core fiber were achieved by creating a small gap between a solid-core fiber and the hollow-core fiber, which were fixed within a low-cost ceramic ferrule. A coupling efficiency of over 50% from free-space excitation laser to the hollow core fiber was obtained through a 350 μm-long solid-core fiber. For proof-of-concept demonstration of bioprocessing monitoring, a series of ethanol and glucose aqueous solutions at different concentrations were used. The limit of detection achieved for the ethanol solutions with our system was ~0.04 vol.% (0.32 g/L). Such an all-fiber microfluidic device is robust, provides Raman measurements with high repeatability and reusability, and is particularly suitable for the in-line monitoring of bioprocesses.

HYDROXYAPATITE, ALGINATE, AND CHITOSAN FOR BONE SCAFFOLDS: SPECTROSCOPY STUDY

2016 ◽  
Vol 19 (2) ◽  
pp. 93-100
Author(s):  
Lalita El Milla
Keyword(s):  
Tissue Engineering ◽  
Bone Tissue Engineering ◽  
Bone Tissue ◽  
Functional Groups ◽  
Bone Growth ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Tissue Engineering Scaffolds ◽  
Hydroxyapatite Powder ◽  
Materials Used

Scaffolds is three dimensional structure that serves as a framework for bone growth. Natural materials are often used in synthesis of bone tissue engineering scaffolds with respect to compliance with the content of the human body. Among the materials used to make scafffold was hydroxyapatite, alginate and chitosan. Hydroxyapatite powder obtained by mixing phosphoric acid and calcium hydroxide, alginate powders extracted from brown algae and chitosan powder acetylated from crab. The purpose of this study was to examine the functional groups of hydroxyapatite, alginate and chitosan. The method used in this study was laboratory experimental using Fourier Transform Infrared (FTIR) spectroscopy for hydroxyapatite, alginate and chitosan powders. The results indicated the presence of functional groups PO43-, O-H and CO32- in hydroxyapatite. In alginate there were O-H, C=O, COOH and C-O-C functional groups, whereas in chitosan there were O-H, N-H, C=O, C-N, and C-O-C. It was concluded that the third material containing functional groups as found in humans that correspond to the scaffolds material in bone tissue engineering.

In vitro Three Dimensional Scaffold-free Construct of Human Adipose-derived Stem Cells in Coculture with Endothelial Cells and Fibroblasts

2017 ◽  
Vol 68 (6) ◽  
pp. 1341-1344
Author(s):  
Grigore Berea ◽  
Gheorghe Gh. Balan ◽  
Vasile Sandru ◽  
Paul Dan Sirbu
Keyword(s):  
Tissue Engineering ◽  
Stem Cells ◽  
Endothelial Cells ◽  
Single Cell ◽  
Cell Line ◽  
Bone Repair ◽  
Umbilical Vein ◽  
Human Fibroblasts ◽  
Three Dimensional ◽  
Adipose Derived Stem Cells

Complex interactions between stem cells, vascular cells and fibroblasts represent the substrate of building microenvironment-embedded 3D structures that can be grafted or added to bone substitute scaffolds in tissue engineering or clinical bone repair. Human Adipose-derived Stem Cells (hASCs), human umbilical vein endothelial cells (HUVECs) and normal dermal human fibroblasts (NDHF) can be mixed together in three dimensional scaffold free constructs and their behaviour will emphasize their potential use as seeding points in bone tissue engineering. Various combinations of the aforementioned cell lines were compared to single cell line culture in terms of size, viability and cell proliferation. At 5 weeks, viability dropped for single cell line spheroids while addition of NDHF to hASC maintained the viability at the same level at 5 weeks Fibroblasts addition to the 3D construct of stem cells and endothelial cells improves viability and reduces proliferation as a marker of cell differentiation toward osteogenic line.

scholarly journals Second sacral sacralalar‐iliac (S2AI) screw placement in adult degenerative scoliosis (ADS) patients: an imaging study

BMC Surgery ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Bing Wu ◽  
Kai Song ◽  
Junyao Cheng ◽  
Pengfei Chi ◽  
Zhaohan Wang ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Imaging Study ◽  
Outer Diameter ◽  
Degenerative Scoliosis ◽  
Female Patients ◽  
Lateral Angle ◽  
Adult Degenerative Scoliosis ◽  
Imaging Characteristics ◽  
Starting Point ◽  
Trajectory Length

Abstract Background The imaging characteristics of sacral sacralalar-iliac (S2AI) screw trajectory in adult degenerative scoliosis (ADS) patients will be determined. Methods S2AI screw trajectories were mapped on three-dimensional computed tomography (3DCT) reconstructions of 40 ADS patients. The starting point, placement plane, screw template, and a circle centered at the lowest point of the ilium inner cortex were set on these images. A tangent line from the starting point to the outer diameter of the circle was selected as the axis of the screw trajectory. The related parameters in different populations were analyzed and compared. Results The trajectory length of S2AI screws in ADS patients was 12.00 ± 0.99 cm, the lateral angle was 41.24 ± 3.92°, the caudal angle was 27.73 ± 6.45°, the distance from the axis of the screw trajectory to the iliosciatic notch was 1.05 ± 0.81 cm, the distance from the axis of the screw trajectory to the upper edge of the acetabulum was 1.85 ± 0.33 cm, and the iliac width was 2.12 ± 1.65 cm. Compared with females, the lateral angle of male ADS patients was decreased, but the trajectory length was increased (P < 0.05). Compared to patients without ADS in previous studies, the lateral angle of male patients was larger, the lateral angle of female patients was increased, and the caudal angle was decreased (P < 0.05). Conclusions There is an ideal trajectory of S2AI screws in ADS patients. A different direction should be noticed in the placement of S2AI screws, especially in female patients.

scholarly journals Advances in tissue engineering of vasculature through three‐dimensional bioprinting

2021 ◽  
Author(s):  
Junjin Zhu ◽  
Yuting Wang ◽  
Linna Zhong ◽  
Fangwei Pan ◽  
Jian Wang
Keyword(s):  
Tissue Engineering ◽  
Three Dimensional

scholarly journals Is Dialdehyde Chitosan a Good Substance to Modify Physicochemical Properties of Biopolymeric Materials?

2021 ◽  
Vol 22 (7) ◽  
pp. 3391
Author(s):  
Sylwia Grabska-Zielińska ◽  
Alina Sionkowska ◽  
Ewa Olewnik-Kruszkowska ◽  
Katarzyna Reczyńska ◽  
Elżbieta Pamuła
Keyword(s):  
Mechanical Properties ◽  
Tissue Engineering ◽  
Physicochemical Properties ◽  
Silk Fibroin ◽  
Three Dimensional ◽  
Microscopy Imaging ◽  
Maximum Deformation ◽  
One Step ◽  
Chitosan Blends ◽  
Fourier Transfer Infrared Spectroscopy

The aim of this work was to compare physicochemical properties of three dimensional scaffolds based on silk fibroin, collagen and chitosan blends, cross-linked with dialdehyde starch (DAS) and dialdehyde chitosan (DAC). DAS was commercially available, while DAC was obtained by one-step synthesis. Structure and physicochemical properties of the materials were characterized using Fourier transfer infrared spectroscopy with attenuated total reflectance device (FTIR-ATR), swelling behavior and water content measurements, porosity and density observations, scanning electron microscopy imaging (SEM), mechanical properties evaluation and thermogravimetric analysis. Metabolic activity with AlamarBlue assay and live/dead fluorescence staining were performed to evaluate the cytocompatibility of the obtained materials with MG-63 osteoblast-like cells. The results showed that the properties of the scaffolds based on silk fibroin, collagen and chitosan can be modified by chemical cross-linking with DAS and DAC. It was found that DAS and DAC have different influence on the properties of biopolymeric scaffolds. Materials cross-linked with DAS were characterized by higher swelling ability (~4000% for DAS cross-linked materials; ~2500% for DAC cross-linked materials), they had lower density (Coll/CTS/30SF scaffold cross-linked with DAS: 21.8 ± 2.4 g/cm3; cross-linked with DAC: 14.6 ± 0.7 g/cm3) and lower mechanical properties (maximum deformation for DAC cross-linked scaffolds was about 69%; for DAS cross-linked scaffolds it was in the range of 12.67 ± 1.51% and 19.83 ± 1.30%) in comparison to materials cross-linked with DAC. Additionally, scaffolds cross-linked with DAS exhibited higher biocompatibility than those cross-linked with DAC. However, the obtained results showed that both types of scaffolds can provide the support required in regenerative medicine and tissue engineering. The scaffolds presented in the present work can be potentially used in bone tissue engineering to facilitate healing of small bone defects.

Sign in / Sign up

Export Citation Format

Share Document