Measurements of Dynamic Viscoelasticity of Poly (vinyl alcohol) Hydrogel for the Development of Blood Vessel Biomodeling

Abstract

In vitro blood vessel biomodeling with realistic mechanical properties and geometrical structures is helpful for training in surgical procedures, especial those used in endovascular treatment. Poly (vinyl alcohol) hydrogel (PVA-H), which is made of Poly (vinyl alcohol) (PVA) and water, may be useful as a material for blood vessel biomodeling due to its low surface friction resistance and good transparency. In order to simulate the mechanical properties of blood vessels, measurements of mechanical properties of PVA-H were carried out with a dynamic mechanical analyzer, and the storage modulus (G') and loss modulus (G'') of PVA-H were obtained. PVA-Hs were prepared by the low-temperature crystallization method. They were made of PVA with various concentrations (C) and degrees of polymerization (DP), and made by blending two kinds of PVA having different DP or saponification values (SV). The G' and G'' of PVA-H increased, as the C or DP of PVA increased, or as the proportion of PVA with higher DP or SV increased. These results indicate that it is possible to obtain PVA-H with desirable dynamic viscoelasticity. Furthermore, it is suggested that PVA-H is stable in the temperature range of 0°C to 40°C, indicating that biomodeling made of PVA-H should be available at 37°C, the physiological temperature. The dynamic viscoelasticity of PVA-H obtained was similar to that of the dog blood vessel measured in previous reports. In conclusion, PVA-H is suggested to be useful as a material of blood vessel biomodeling.

Friction behaviour of hydrophilic lubricious coatings for medical device applications

“…It is apparent from previous research into biomechanical modelling and the development of synthetic blood vessels for clinicians' training devices that PVA hydrogel can be used to simulate the interior of blood vessels [32][33][34]. In addition to having similar mechanical properties, PVA hydrogels have a high water content resulting in a low surface friction resistance and low interfacial energy with water or biological fluids [35], thus these materials canmimic human soft tissues.…”

Evaluation of the effect of catheter on the guidewire motion in a blood vessel model by physical and numerical simulations

“…Lawton et al (2000) employed a finite element discretization to model the catheter and to compute its deformed configurations. On the other hand, several simulators using blood vessel biomodels made of silicone rubber (Ikeda et al, 2005;Wetzel et al, 2005) or poly (vinyl alcohol) hydrogel (PVA-H) (Kosukegawa et al, 2008;Ohta et al, 2004), mimicking a living tissue, have also been developed. Many catheter simulators are developed for training, and include a haptic interface, with which medical students or physicians operate the virtual guidewire, to provide feedback to the operator yielding a sensation similar to that encountered in actual catheter insertion.…”

Friction Properties of Poly(vinyl alcohol) Hydrogel: Effects of Degree of Polymerization and Saponification Value

“…The crystalline regions are formed mainly by hydrogen bonds on the hydrophilic groups, while the amorphous regions include flexible chains without hydrogen bonds. Therefore, its thermal and mechanical properties can be flexibly controlled by changing the PVA factors such as concentration, polymerization, and saponification [4][5][6][7][8][9][10][11].…”

“…Higher DP of PVA induces increased entanglement of the polymer chains, and higher SV induces decreased amorphous regions. The amorphous regions may act as a damper, and consequently the variation of the inner crystalline structure appears as the different thermal and mechanical properties[4][5][6][7][8][9]. As shown inFig.…”