Market
leaders in temperature controlled microscopy, Linkam Scientific Instruments,
have been chosen by the Physics Department of the University of Liverpool to
study the effects of controlling stresses applied during the growth of collagen
secreted from human fibroblast cells.
The research goal of Senior Research Assistant, Dr Caroline Smith, and her
colleagues at the University of Liverpool is to advance the treatment of tendon
injuries by developing a method of growing oriented human collagen.
To achieve this and to gain a fundamental understanding of the process, Dr.
Smith is using the optical technique of reflection anisotropy spectroscopy to
monitor the extent to which collagen, grown by mouse fibroblast cells on
elastomeric substrates, is oriented when subjected to a regular uniaxial stress
mounted in a Linkam TST350 tensile stage.
For the experiment, small wells capable of holding liquid were fabricated from
polydimethylsiloxane (PDMS) to fit in the Tensile Stress Tester. The effect of
stretching the PDMS as a function of applied stress was investigated initially
to determine the effect of stress on the substrate. (J. Phys. D: Appl. Phys.
43,
245301 (2010)). L929 murine fibroblasts cells were cultured at 37?C in a 5 %
CO2 atmosphere in Dulbeccos Modified Eagles Medium (DMEM) (Sigma) supplemented
with 5 % Foetal Bovine Serum (Invitrogen) and 1 % Penicillin/Streptomycin
antibiotics (Sigma). The culture medium was replenished daily during the
cycling period. The cells were then subject to cyclic stress for 7 days. After
7 days, the wells were removed from the incubator and washed with Dulbecco's
Phosphate Buffered Saline (DPBS, Sigma). The cell layer was dispersed in 0.05 %
Trypsin/EDTA (Sigma) incubated for 3 min and subjected to gentle agitation to remove
the cells without damaging the collagen layer. After removal of the cells the
collagen secreted from the cells could be investigated by optical microscopy
and reflection anisotropy spectroscopy.
The ability to choose a wide range of cyclic speeds to relate back to the
growth of collagen is very useful. Initially, Dr Smith thought about making her
own TST but having a small unit that could control the cyclic stress and also
measure stress/strain curves at the same would be very difficult to manufacture
in-house. Hence, the Linkam unit was purchased.
The TST350 stage is built with two precision ground stainless steel lead screws
to maintain perfect uniform vertical and horizontal alignment. The sample jaws
move in opposite directions to maintain sample in both reflected and
transmitted microscope fields of view. Temperature control and accuracy is
excellent with a range from -196°C to 350°C with 0.01°C control and up to
30°C/min rates, with virtually no temperature feedback to the measurement of
force. Samples can be quickly loaded into the jaws and a test run can be
performed in seconds. The data feedback from the force transducer, designed and
built in-house, can be used to display an online plot of the force/distance
when the jaws are moving at constant speed or when speed is varied to maintain
a constant force. The speed of the jaws, force applied and distance moved can
all be varied relative to the cell temperature. The sample chamber is sealed
and can be controlled with various inert gases via the precision click fit
valves built onto sides of the stage.
Visit the
Linkam website (
www.linkam.co.uk)
today and learn about the broad range of applications in the field of
temperature controlled microscopy.
Subscribe to any of our newsletters for the latest on new laboratory products, industry news, case studies and much more!
Request your free copies HERE
Popular this Month
Top 10 most popular articles this month
Today's Picks
Looking for a Supplier?
Search by company or by product
Please note Lab Bulletin does not sell, supply any of the products featured on this website. If you have an enquiry, please use the contact form below the article or company profile and we will send your request to the supplier so that they can contact you directly.
Lab Bulletin is published by newleaf marketing communications ltd.