Search results

1 – 10 of 247
Article
Publication date: 22 June 2020

Zhanshe Guo, Taiyi Zhang, Xiangdang Liang and Yutong Wang

The study of vascular mechanics is important. The purpose of this paper is to present an apparatus to measure the biomechanical properties of blood vessels, which can be used for…

Abstract

Purpose

The study of vascular mechanics is important. The purpose of this paper is to present an apparatus to measure the biomechanical properties of blood vessels, which can be used for tensile test and fatigue test.

Design/methodology/approach

This equipment consists of a mechanical test platform, a hardware circuit based on FPGA and control software. The torque generated by stepper motor is converted to axial force by ball screw, and the vascular specimen is stretched axially. The tension is measured by a load cell, and the displacement is recorded by a grating displacement sensor.

Findings

According to the results of calibration experiment and stability experiment, the linearity error of the system is 0.251, the hysteresis error is 0.047, the repeatability error is 0.185, the comprehensive error is 0.315 and the standard deviation of the output is less than 0.01 N. A test of animal vascular mechanical properties was carried out, and the results are consistent with the theory.

Originality/value

This apparatus is designed to measure biomechanical properties of blood vessels, and the results of experiments indicate that it is stable and reliable. This work is valuable for studying vascular disease and testing artificial blood vessels.

Details

Sensor Review, vol. 40 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 18 January 2011

Amal Owida, Rui Chen, Shital Patel, Yos Morsi and Xiumei Mo

The purpose of this paper is to prepare a new combined method of rapid prototyping, fused deposition modeling (FDM) and electrospinning for the fabrication of coronary artery…

1799

Abstract

Purpose

The purpose of this paper is to prepare a new combined method of rapid prototyping, fused deposition modeling (FDM) and electrospinning for the fabrication of coronary artery bypass graft (CABG).

Design/methodology/approach

A dynamically optimum design of blood vessel graft was constructed using FDM and electrospinning. Fabrication of 3‐D CABG model was constructed using pro‐engineer based on the optimum hemodynamic analysis and was converted to an stereolithography file format which was imported to the Magic software where it was edited to a high‐resolution contour. The model was then created from acrylonitrile butadiene styrene which was used as a collector for electrospinning fabrication. For the electrospinning thermoplastic polyurethane was dissolved with hexafluoroisopropanol. The voltage applied for electrospinning was 15 kV where the solid FDM model was used to collect nanofibers at fixed distance.

Findings

The properties of the fabricated vessel agreed well with those of human artery. The proposed method can be effectively used for the fabrication of an optimized graft design. This proposed method has been proved as a promising fabrication processes in fabricating a specially designed graft with the correct physical and mechanical properties.

Originality/value

The proposed method is novel and combines the advantages of both FDM and electrospinning techniques.

Details

Rapid Prototyping Journal, vol. 17 no. 1
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 1 February 2021

Rudranarayan Kandi, Pulak Mohan Pandey, Misba Majood and Sujata Mohanty

This paper aims to discuss the successful fabrication of customized tubular scaffolds for tracheal tissue engineering with a novel route using solvent-based extrusion 3D printing.

Abstract

Purpose

This paper aims to discuss the successful fabrication of customized tubular scaffolds for tracheal tissue engineering with a novel route using solvent-based extrusion 3D printing.

Design/methodology/approach

The manufacturing approach involved extrusion of polymeric ink over a rotating predefined pattern to construct customized tubular structure of polycaprolactone (PCL) and polyurethane (PU). Dimensional deviation in thickness of scaffolds were calculated for various layer thicknesses of 3D printing. Physical and chemical properties of scaffolds were investigated by scanning electron microscope (SEM), contact angle measurement, Fourier Transform Infrared Spectroscopy (FTIR) and X-ray diffraction (XRD). Mechanical characterizations were performed, and the results were compared to the reported properties of human native trachea from previous reports. Additionally, in vitro cytotoxicity of the fabricated scaffolds was studied in terms of cell proliferation, cell adhesion and hemagglutination assay.

Findings

The developed fabrication route was flexible and accurate by printing customized tubular scaffolds of various scales. Physiochemical results showed good miscibility of PCL/PU blend, and decrease in crystalline nature of blend with the addition of PU. Preliminary mechanical assessments illustrated comparable mechanical properties with the native human trachea. Longitudinal compression test reported outstanding strength and flexibility to maintain an unobstructed lumen, necessary for the patency. Furthermore, the scaffolds were found to be biocompatible to promote cell adhesion and proliferation from the in vitro cytotoxicity results.

Practical implications

The attempt can potentially meet the demand for flexible tubular scaffolds that ease the concerns such as availability of suitable organ donors.

Originality/value

3D printing over accurate predefined templates to fabricate customized grafts gives novelty to the present method. Various customized scaffolds were compared with conventional cylindrical scaffold in terms of flexibility.

Details

Rapid Prototyping Journal, vol. 27 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 17 October 2017

Yang Wu, Jerry Fuh, Yoke San Wong and Jie Sun

Fabricating functionally graded scaffolds to mimic the complex spatial distributions of the composition, micro-structure and functionality of native tissues will be one of the key…

Abstract

Purpose

Fabricating functionally graded scaffolds to mimic the complex spatial distributions of the composition, micro-structure and functionality of native tissues will be one of the key objectives for future tissue engineering research. This study aims to create a scaffold to mimic functionally-graded tissue using a hybrid process, which incorporated electrospun polycaprolactone (PCL) and electrosprayed hydroxyapatite (HA) in a simple pathway.

Design/methodology/approach

The PCL and HA were dispensed simultaneously from different positions to form a layer on a rotational mandrel, and a gradient construct was achieved by adjusting dispensing rates of both materials.

Findings

The morphology of scaffolds changed gradually from one layer to another layer with the change of the dispensing conditions of the two materials. The elemental distribution analysis revealed that C/Ca ratio linearly increased with certain dispensing rate ratio of PCL:HA. In addition, the thickness, mechanical properties (i.e. ultimate tensile stress and Young’s modulus), surface roughness and water contact angle of each layer changed accordingly with the variation of dispensing rate of PCL and HA, and the diameter distributions of PCL fibres and HA particles did not vary significantly.

Originality/value

This study showed the hybrid process has the potential to be used in fabrication of scaffold with functionally graded structure for tissue engineering applications, especially for mimicking the nature of the native 3D tendon–bone interface.

Details

Rapid Prototyping Journal, vol. 23 no. 6
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 1 November 2000

Jaroslav Mackerle

Gives a bibliographical review of the finite element methods (FEMs) applied in biomedicine from the theoretical as well as practical points of view. The bibliography at the end…

1347

Abstract

Gives a bibliographical review of the finite element methods (FEMs) applied in biomedicine from the theoretical as well as practical points of view. The bibliography at the end of the paper contains 748 references to papers, conference proceedings and theses/dissertations dealing with the finite element analyses and simulations in biomedicine that were published between 1985 and 1999.

Details

Engineering Computations, vol. 17 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 December 2004

George K. Stylios

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects…

3545

Abstract

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Details

International Journal of Clothing Science and Technology, vol. 16 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 December 2001

George Stylios

Discusses the 6th ITCRR, its breadth of textile and clothing research activity, plus the encouragement given to workers in this field and its related areas. States that, within…

1078

Abstract

Discusses the 6th ITCRR, its breadth of textile and clothing research activity, plus the encouragement given to workers in this field and its related areas. States that, within the newer research areas under the microscope of the community involved, technical textiles focuses on new, ‘smart’ garments and the initiatives in this field in both the UK and the international community at large. Covers this subject at length.

Details

International Journal of Clothing Science and Technology, vol. 13 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 December 2003

George K. Stylios

Examines the ninth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects…

1197

Abstract

Examines the ninth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Details

International Journal of Clothing Science and Technology, vol. 15 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 December 2002

George K. Stylios

Looks at the eighth published year of the ITCRR and the research, from far and near, involved in this. Muses on the fact that, though all the usual processes are to the fore, the…

Abstract

Looks at the eighth published year of the ITCRR and the research, from far and near, involved in this. Muses on the fact that, though all the usual processes are to the fore, the downside part of the industry is garment making which is the least developed side. Posits that the manufacture of clothing needs to become more technologically advanced as does retailing. Closes by emphasising support for the community in all its efforts.

Details

International Journal of Clothing Science and Technology, vol. 14 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 18 February 2022

Jasvinder Singh, Pulak Mohan Pandey, Tejinder Kaur and Neetu Singh

The purpose of this paper is to fabricate pre-existing geometries of the stents using solvent cast 3D printing (SC3P) and encapsulation of each stent with heparin drug by using…

Abstract

Purpose

The purpose of this paper is to fabricate pre-existing geometries of the stents using solvent cast 3D printing (SC3P) and encapsulation of each stent with heparin drug by using aminolysis reaction.

Design/methodology/approach

The iron pentacarbonyl powder and poly-ɛ-caprolactone blend (PCIP) were used to print stent designs of Art18z, Palmaz-Schatz and Abbott Bvs1.1. The properties of antithrombosis, anticoagulation and blood compatibility were introduced in the stents by conjugation of heparin drug via the aminolysis process. The aminolysis process was confirmed by energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy due to presence of amide group and nitrogen peak in the respective analysis. Biological studies were performed to depict the cell viability, hemocompatibility and antithrombotic properties. Besides, mechanical behaviors were analyzed to study the behavior of the stents under radial compression load and bending load.

Findings

The amount of heparin immobilized on the Art18z, Palmaz-Schatz and Abbott Bvs1.1 stents were 255 ± 27, 222 ± 30 and 212 ± 13 µg, respectively. The cell viability studies using L929 fibroblast cells confirmed the cytocompatibility of the stents. The heparinized SC3P printed stents displayed excellent thrombo-resistance, anticoagulation properties and hemocompatibility as confirmed by blood coagulation analysis, platelet adhesion test and hemolysis analysis. Besides, mechanical behavior was found in context of the real-life stents. All these assessments confirmed that the developed stents have the potential to be used in the real environment of coronary arteries.

Originality/value

Various customized shaped biodegradable stents were fabricated using 3D printing technique and encapsulated with heparin drug using aminolysis process.

1 – 10 of 247