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Researcher, University of Bristol

Our lab was interested in purchasing a syringe pump from WPI. The company's support was helpful in identifying the required model and even informed us of model-specific limitations (which were of no concern for our intended use). The overall processing and delivery was exceedingly fast – less tha...
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BiOTESTER: A fully equipped biaxial test system built specifically for biomaterials

  • Overview
  • Specifications
  • Accessories
  • Citations
  • Related Products


BIOTESTER Biorakes with tissue mounted on a BioTester. The sample size is much smaller than a US penny One view from the software with actual live video from the mounted sample. Biorakes Pulley System Clamps

There are 6 images available to view - click to enlarge and scroll through the product gallery.

Biotester Datasheet
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Uniaxial U-Stretch
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Why measure mechanical properties?
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Stress-strain in human sclera
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The BioTester provides researchers with an easy-to-use, affordable test instrument to characterize soft tissues and biomaterials. This biaxial test system captures and graphically displays live time, force, and synchronized video images for results analysis and verification. Data is easily exported to standard spreadsheet programs. 

  • High performance actuators (2 per axis) capable of μm positional resolution for accurate test motion.
  • Inline overload-protected load cell on each axis
  • High resolution CCD camera to collect time synchronized images for post test analysis
  • Temperature controlled media bath
  • Patented attachment system facilitates rapid and accurate specimen attachment
  • Optional use of hook-and-suture or grip based attachment systems
  • User-controlled test routines for multi-modal cyclic, simple, and relaxation testing over a wide range of strain rates
  • Data output as a comma separated value text files for easy import into a variety of spread sheet and data analysis programs
  • Simple USB connection to a Windows-based host computer
  • Specimen Size: 3mm to 15mm
  • Load Cell Capacities (N): 0.5, 1.5, 2.5, 5, 10, 23
  • Load Cell Accuracies: 0.2% of capacity Max Displacement
  • Rate: 10mm/s Image Rate: 15Hz
  • Image Resolution: 1280 X 960 pixels
  • Max. Temperature: 40°C

Sample Mounting Systems

The BioRake sample mounting system is CellScale’s patented method for attaching soft tissues and biomaterials.

 Each tine is electrochemically sharpened to easily pierce both the toughest and most delicate tissue samples. Each set is permanently attached to a common base to allow simultaneous puncture of all 20 attachment points. The BioRakes are magnetically mounted for easy removal for cleaning or replacement and for simple transition between BioRake, Balanced Pulley, and Clamp mounting systems.

To perform testing, samples are positioned and raised into place using the manual lift mechanism and pressure is applied to insert the hooks in the tissue. The sample is thus mounted and ready for analysis within a few seconds. The mounting is consistent, accurate and easy.

BioRakes are available with tine spacing ranging from 0.7mm to 2.2mm to accommodate specimens from 3 to 15mm in size.

The balanced pulley sample mounting system is CellScale’s attachment method for ensuring zero shear stress during biaxial testing.


Two double-ended custom suture hooks are used to create 4 attachment points on each side of the specimen. A two-stage stainless steel pulley mechanism ensures that each of the sutures is held at the same tension during the test.

The pulley mechanisms are magnetically mounted for easy removal for cleaning and for simple transition between BioRake, Balanced Pulley, and Clamp mounting systems.

The clamp sample mounting system is CellScale’s attachment method for testing to failure.


Using a cruciform specimen allows the attachment sites, which are inherently weaker than the base material, to be moved away from the gauge area of the specimen. The clamps allow the specimen to be loaded easily and held securely.

The stainless steel clamping mechanisms are mounted over the same brackets used for the other attachment systems to allow for fast and easy transition between BioRake, Balanced Pulley, and Clamp mounting systems.

Custom clamp designs can also be made to tailor the clamp force and clamping surface to your tissue. 

Video Overviews 



Force Capacity  500, 100, 2500, 5000mN, 10N, 23N
Force Accuracy  0.2% of force capacity
Max. Elongation Rate 10mm/s
Max. Strain Rate (5mm specimen) 200%/s
Spatial Resolution (Actuator)  >0.1μm 
Spatial Accuracy (Acuator) 10μm 
Spatial Resolution (Image Analysis)  1/8 pixel 
Max. Force Data Rate 100Hz
Image Rate 1280 x 960 -15Hz



Abbeele, M. Van den, & Smoljkic, M. (2015). Characterisation of mechanical properties of human pulmonary and aortic tissue. … European Conference of …. Retrieved from

Argento, G., & Jonge, N. de. (2014). Modeling the impact of scaffold architecture and mechanical loading on collagen turnover in engineered cardiovascular tissues. …  and modeling in …. Retrieved from

Ballotta, V., Driessen-Mol, A., Bouten, C., & Baaijens, F. (2014). Strain-dependent modulation of macrophage polarization within scaffolds. Biomaterials. Retrieved from

Grimes, K., & Voorhees, A. (2014). Cardiac function of the naked mole-rat: ecophysiological responses to working underground. American Journal of …. Retrieved from

Hill, M., Simon, M., & Valdez-Jasso, D. (2014). Structural and Mechanical Adaptations of Right Ventricle Free Wall Myocardium to Pressure Overload. Annals of biomedical  …. Retrieved from


Kahlon, A., Hurtig, M., & Gordon, K. (2014). Regional and depth variability of porcine meniscal mechanical properties through biaxial testing. Journal of the Mechanical Behavior of  …. Retrieved from

Kavanagh, E., & Grace, P. (2014). The biaxial mechanical behaviour of abdominal aortic aneurysm intraluminal thrombus: Classification of morphology and the determination of layer and region specific. Journal of  …. Retrieved from

Monaco, L. (2014). Comparative Analysis of Selected Model Species used in Intervertebral Disc Research. Retrieved from

O’Leary, S, Doyle, B., & McGloughlin, T. (2014). The impact of long term freezing on the mechanical properties of porcine aortic tissue. Journal of the Mechanical Behavior of  …. Retrieved from

O’Leary, S, Healey, D., & Kavanagh, E. (2014). The biaxial biomechanical behaviour of abdominal aortic aneurysm. On the Characterisation  …. Retrieved from

O’Leary, SA. (2014). On the characterisation of abdominal aortic tissues. Retrieved from

O’Leary, SA, & Healey, D. (2014). The Biaxial Biomechanical Behavior of Abdominal Aortic Aneurysm Tissue. Annals of biomedical  …. Retrieved from

Quiroga, J. P., Emans, P., & Wilson, W. (2014). Should a native depth-dependent distribution of human meniscus constitutive components be considered in FEA-models of the knee joint? Journal of the  …. Retrieved from

Soares, A. (2014). Mechanics of the pulmonary valve in the aortic position. Journal of the  …. Retrieved from




UStretch - A versatile uniaxial benchtop mechanical tester

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