A dynamic inline sample thermoregulation unit for flow cytometry.
BACKGROUND
Flow cytometry is a valuable tool for the study of cellular and molecular interactions. We sought to develop instrumentation that would allow accurate and precise inline dynamic temperature control of flow cytometry samples in order to expand the analytical capabilities of flow cytometry.


METHODS
Using a temperature controller, DC power supply, and a Peltier module, we designed a temperature control circuit that regulates the temperature of a heat transfer block. The heat transfer block surrounds the sample line to efficiently heat and cool the sample. We attached DNA oligomers to microspheres and observed the denaturation of fluorescently labeled complementary oligomers to verify that the sample was achieving the desired temperature.


RESULTS
The inline thermoregulation unit can ramp between 30 and 95 degrees C (>2 degrees C per second) within 30 s repeatedly. The accuracy of the instrument was verified by comparing the observed melting temperatures of the oligomer sets to the predicted values. These values varied within 6% of the predicted and were reproducible over a variety of conditions.


CONCLUSIONS
The apparatus we constructed accurately and dynamically controls the sample temperature of inline samples. Flow cytometers equipped with our inline thermoregulation unit will be able to conveniently use temperature as a robust experimental parameter.
Graves
S W
SW
National Flow Cytometry Resource, Biosciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Habbersett
R C
RC
Nolan
J P
JP
D001483:Base Sequence; D002138:Calibration; D004581:Electronics; D005434:Flow Cytometry / Q000295:instrumentation* / Q000379:methods; D008863:Microspheres; D009691:Nucleic Acid Denaturation; D009838:Oligodeoxyribonucleotides / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015203:Reproducibility of Results; D013696:Temperature; D013997:Time Factors
D009838:Oligodeoxyribonucleotides