'Micro-rack' measures cell mechanical properties

Researchers at the National Institute of Standards and Technology have developed a microelectromechanical system (MEMS) cell-stretcher that can measure the mechanical properties of a living cell, such as its ability to stick to a surface. The new device is expected to enable novel studies of cell mechanics, which influence basic cell functions such as growth and division, and diseases such as sickle cell anemia and asthma.

The prototype device, described in a new paper, is believed to be the only technique for studying bulk mechanical properties of a single, whole cell while it is spreading out and sticking to a substrate as it would in the body, says the designer, NIST bioengineer David Serrell. Other biomechanical test methods focus on individual cell components or entire tissues.

The heart of the NIST device is a circular cell platform 200 micrometers wide, a tiny fleck just barely visible to the naked eye. The two halves of the circle can be pulled as far as 100 micrometers apart under computer control, while the force needed to separate them is measured by sensors. In a demonstration using a connective tissue cell, the cell is placed on the center of the platform, allowed to spread and adhere for several hours, and then pulled slowly apart until it detaches. In NIST experiments, the cells let go of the substrate at a force of about 1500 nanonewtons.

The devices are made on silicon wafers using a NIST-developed process based on standard chip-making techniques. The geometry of any component can be altered to suit a variety of cell types and experiments. The apparatus could be used for a variety of studies, such as effects of cyclic strain on cells, the elasticity of their response to force, or the effectiveness of different proteins used to encourage attachment of the cells, Serrell says. The newest version of the device, fabricated but not yet tested, is made of silicon nitride, a transparent material that will allow simultaneous real-time imaging of the interior of the cells and perhaps provide new insights into the relationships of force and cell mechanical properties and structure.

Citation: D.B. Serrell, T. Oreskovic, A.J. Slifka, R.L. Mahajan and D.S. Finch. A uniaxial bioMEMS device for quantitative force-displacement measurements. Biomedical Microdevices. Available online.

Source: National Institute of Standards and Technology

Related stories:

Controlling light with sound: new liquid camera lens as simple as water and vibration
New miniature image-capturing technology powered by water, sound, and surface tension could lead to smarter and lighter cameras in everything from cell phones and automobiles to autonomous robots and miniature spy planes.
Researchers discover unexpected properties of materials in lowermost mantle
Materials deep inside Earth have unexpected atomic properties that might force earth scientists to revise their models of Earth's internal processes, a team of researchers has discovered.
Bioengineers develop 'microscope on a chip'
Researchers at the California Institute of Technology have turned science fiction into reality with their development of a super-compact high-resolution microscope, small enough to fit on a finger tip. This "microscopic microscope" operates without lenses but has the magnifying power of a top-quality optical microscope, can be used in the field to analyze blood samples for malaria or check water supplies for giardia and other pathogens, and can be mass-produced for around $10.
Researchers coat titanium with polymer to improve integration of joint replacements
Research at the Georgia Institute of Technology shows that coating a titanium implant with a new biologically inspired material enhances tissue healing, improves bone growth around the implant and strengthens the attachment and integration of the implant to the bone.
New electrostatic-based DNA microarray technique could revolutionize medical diagnostics
The dream of personalized medicine — in which diagnostics, risk predictions and treatment decisions are based on a patient's genetic profile — may be on the verge of being expanded beyond the wealthiest of nations with state-of-the-art clinics.
Nanotech: Hot Technology Gets a Cool Down
It’s the hottest technology – featherweight laptops that feature rapid response, crisp graphics and operate complex computer games; slim cell phones with Web-browsing capabilities, store high resolution photos and keep track of our lives; credit card-sized MP3 players that store thousands of songs and hours of videos.
Princeton researchers envision a more secure Internet
Like human society itself, the world's computerized infrastructure is wondrously complex, both spectacularly fertile and deeply flawed.
New nanostructured thin film shows promise for efficient solar energy conversion
In the race to make solar cells cheaper and more efficient, many researchers and start-up companies are betting on new designs that exploit nanostructures--materials engineered on the scale of a billionth of a meter. Using nanotechnology, researchers can experiment with and control how a material generates, captures, transports, and stores free electrons--properties that are important for the conversion of sunlight into electricity.

News discussion:

General Science news