Medical application - Puncture testing on plasma membrane

Customer needs and challenges

ANDILOG collaborated with searchers from the medical industry to supply a puncture testing measuring device. The goals of the searchers was to charaterize and quantify the microstructural constituents.The needs were to provide:

• A complete solution which is able to test and characterize plasma membranes, in order to make comparisons across studies.
• A real-time characterization methods which is capable of following the process of membrane penetration

It is critical to be able to characterize the force preceding the first penetration event on cellular, as it gives access to the cytoplasm.

Note: Similar tests have been pursued on tissues in order to characterize the strength and elasticity properties and so have a better understanding of the tissues’ healing mechanism.

ANDILOG Solution

To reply to this challenge of measuring the cell penetration force, ANDILOG supplied:

• The motorized and automated testing stand STENTOR CC, which is able to repeat with high accuracy the same process on a large amount of samples
• a puncture fixture, which clamps and provides rigidity to the plasma membrane specimen
• The control and acquisition software CALIFORT, which collects data for later examination of the membrane rupture

Results

Researchers were able to clearly identify the membrane penetration forces, by collecting the force at first breakthrough and then compared the penetration forces on treated cells for further research purposes.

The collected results at the end of the testing protocol were maximum force, force at break, and penetration distance.

ANDILOG Products

ANDILOG was able to answer to this challenge by offering the computerized testing machine STENTOR CC which is controlled through the software CALIFORT; and a puncture fixture used to determine the resistance of a material to the penetration of a probe. The penetration event corresponds to advancements of the probe toward the specimen.

• > The STENTOR CC is a motorized testing machine able to perform tensile and compression test at a constant speed rate. The load cell can be sized accordingly to the testing requirements and are available from 10N to 5000N.
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• > The puncture fixture is composed by a base with anti-slip ring which hold and secure the specimen in place, when the probe (or puncture plunger) is used to penetrate through the material (available in various shape: cylindrical, spherical, with sharp edges, radiused edges or needle shaped).
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• > The CALIFORT software controls the motorized test stand. It allows to configure testing protocols with multiple steps, automatically performs calculations, stores data and edits reports comparing results

How it works

Operating principle:

• Test material is cut into 3x3in square, it is critical to have an uniform specimen
• Specimen is held by the set of clamping rings offered by the puncture fixation
• The puncture fixation is attached to the working area of the testing system STENTOR CC
• A probe is attached to the load cell on the moving crosshead of the testing system
• The tester goes in down direction, and applies a small compression force (< 1 lb) to the specimen through the probe
• The force and displacement value are zeroed
• The STENTOR CC continues the test at a constant rate of crosshead movement according to the specification and continues until the specimen rupture
• The force is loaded up onto the specimen as the probe advanced
• This force relaxed transiently when a penetration occurred
• Penetration event is automatically detected and recorded by the CALIFORT
• The STENTOR CC reverses its movement to return to its original position; the probe is retracted from the specimen.

Our key added value

Our added value has been underlined by our customer by our capacity to coordinate approaches and method effectively. We have been able to react and answer quickly to the needs of providing a full compatible and advanced device. The main advantages of our measuring solutions are:

• Repeatable results with automatic pre-defined calculations
• Slow rate penetration speed in order to characterize with accuracy the resistance properties
• Full traceability of results thanks to the data acquisition software

ANDILOG's force gauges are specifically tailored towards quality assurance and research, for further information please contact ANDILOG’s Team.