Mechanical Shearing
Mechanical Shearing - Related Videos
04:53
A Novel Capsulorhexis Technique Using Shearing Forces with Cystotome
0 Views •
Cited by 5 •
2010
This video demonstrates a novel capsulorhexis technique in modern cataract surgery. Capsulorhexis is the most difficult and important part of phacoemulsification surgery.
13:28
Introducing Shear Stress in the Study of Bacterial Adhesion
0 Views •
Cited by 9 •
2011
During the infection process, a key step is the adhesion of pathogens with host cells. In most instances this adhesion step occurs in the presence of mechanical stress generated by flowing liquid. We describe a technique that introduces shear stress as an important parameter in the study of bacterial adhesion.
09:20
The Assembly and Application of 'Shear Rings': A Novel Endothelial Model for Orbital, Unidirectional and Periodic Fluid Flow and Shear Stress
0 Views •
Cited by 10 •
2016
Different levels and patterns of fluid shear are known to modulate endothelial gene expression, phenotype and susceptibility to disease. We discuss the assembly and use of 'shear rings': a model that produces unidirectional, periodic shear stress patterns. Shear rings are simple to assemble, economical and can produce high cell yields.
03:11
The Effects of Shear Stress on Platelets Treated with Antibodies Against Mechanosensory Receptors
0 Views •
2025
This video demonstrates the method to assess the impact of shear stress on platelets. Antibody treatment induces dissociation and conformational changes in mechanoreceptor complexes, activating the platelets and expressing markers on the surface. These markers are observed via immunostaining and flow cytometry.
01:18
Shearing Stress
0 Views •
2026
Shearing stress, denoted by the Greek letter tau (τ), is stress caused by forces acting transversely on an object. These forces create internal ones within the entity in the plane where the external forces are applied. The resultant of these internal forces is the shear in the section. The average shearing stress can be calculated by dividing the shear by the area of the cross-section. However, this is an average value as the distribution of shearing stress across a section varies. It can...
FAQs
Mechanical shearing disrupts biological samples by transferring controlled physical stress through tools such as rotor-stator blades, homogenizers, needles, or sonicators. That stress can break membranes and separate cellular structures, allowing intracellular material to become available for downstream analysis. The balance is important: insufficient force may leave cells intact, whereas excessive treatment can compromise the molecules or organelles being studied.
The main variables are applied force, treatment duration, temperature, and sample composition. Increasing force or extending treatment can change how thoroughly a sample is disrupted, while temperature control helps preserve target components during processing. Because tissues and cell preparations differ in composition, researchers adjust these conditions rather than assuming one setting will produce the same degree of disruption across all samples.
Mechanical shearing relies on physical stress as the primary disruptive input, whereas chemical lysis uses chemical action as its primary basis. This distinction matters when planning sample preparation because the chosen approach affects how membranes and cellular structures are opened. Mechanical treatment is therefore selected when controlled physical disruption is appropriate for the intended protein, nucleic acid, organelle, or tissue analysis.
Different analyses require different levels of access to cellular material. A preparation intended to examine internal molecules may need sufficient disruption to expose them, while work involving organelles requires conditions that avoid unnecessary damage. Controlling the extent of shearing helps balance accessibility with preservation, improving the suitability of the resulting sample for biochemical, molecular, or structural analysis.
A basic workflow begins by selecting a suitable shearing device, applying physical force for a controlled duration, and monitoring conditions such as temperature. Researchers then use the disrupted material for the planned analysis, which may include protein extraction, nucleic acid preparation, tissue homogenization, microscopy, or biochemical assays. Device choice and treatment intensity should reflect the sample and the component of interest.
Homogenizers, rotor-stator blades, needles, and sonicators all supply physical stress, but they represent different equipment choices for processing biological material. Selection depends on the sample type, desired degree of disruption, and the need to preserve target molecules or organelles. Comparing these factors helps researchers avoid treating every sample with identical mechanical conditions and supports more consistent preparation.
Mechanical shearing connects physical sample preparation to several biological research workflows. It can support cell lysis, protein extraction, nucleic acid preparation, tissue homogenization, microscopy, and biochemical assays. These applications depend on matching disruption conditions to the intended analysis, because the useful outcome is not simply a broken sample but access to target material in a form suitable for measurement.