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The new SmartPower 4000 power supply is an all-purpose power supply
Douglas Drake Michelle Cayouette Lisa Filippone
Bob LeSchofs
Stratagene
Figure 1: The SmartPower 4000 Power Supply
Stratagene has developed the new SmartPower 4000 power supply, an all-in-one power supply for any electrophoretic application. The SmartPower 4000 power supply has been designed for the high-voltage, low-current requirements of DNA sequencing gels as well as for the low-voltage, high-current requirements of horizontal DNA gels and vertical protein gels. With its broad power range and four sets of output jacks, the SmartPower 4000 power supply is the perfect one-source power supply for running a variety of different experiments or for high-volume applications.
In 1990, Stratagene introduced the FeatherVolt power supplies,* a uniquely designed line of power supplies for all types of electrophoresis research. The FeatherVolt 500, 2000 and 3000 volt power supplies were smaller in size and lighter in weight than conventional high-voltage power supplies. When used in conjunction with a StrataTherm temperature controller,** the FeatherVolt 3000 power supply1 allowed researchers to regulate gel temperature during electrophoresis by controlling voltage output. For the first time, sequencing gels could be run at constant temperatures to reduce band compressions. Since 1991, Stratagene has been awarded several patents1 for the compact and lightweight design of the FeatherVolt power supplies and their innovative temperature regulation system.
Stratagene has taken the patented FeatherVolt technology and developed the
SmartPower 4000 power supply, a new, more advanced power supply that replaces
all three of the FeatherVolt models. The compact, lightweight design of the
SmartPower 4000 unit is similar to the design of the FeatherVolt power supplies;
however, the SmartPower 4000 power supply has an all-purpose format that makes
it ideal for all electrophoretic applications. The unit has broad voltage,
current and power control ranges that make it powerful and multifunctional
for both horizontal gels and sequencing gels. Four sets of output jacks enable
multiple similar gels to be run at the same voltage simultaneously. The
SmartPower 4000 power supply features a built-in StrataTherm temperature
controller that allows direct regulation of sequencing gel temperatures. The
SmartPower 4000 power supply is programmable, and can store up to 15
user-defined and named programs. A built-in timer can be used for elapsed-time
monitoring and for automatic timing of runs. Both current and power can be
monitored on each output jack independently, which allows better control of each
experimental condition. In addition, the SmartPower 4000 power supply has
constant voltage, current, power or temperature controls with an automatic
crossover capability that continually adjusts during gel electrophoresis to
maintain the selected run condition.The SmartPower 4000 power supply
incorporates numerous safety features, including a no-load detection system,
which prevents operation if nothing is connected, and a sudden-load change
sensor, which alerts the user to extreme changes in running conditions.
Ideal For All Applications
To show the versatility of this power supply, we have tested the SmartPower 4000 power supply in a number of applications. These applications include DNA sequencing, horizontal agarose gel electrophoresis, precast protein gel electrophoresis and electroelution.
figure 2
DNA Sequencing. In figure 2, the SmartPower 4000 power supply was used in conjunction with the CastAway system and precast gels to obtain sequence from M13mp18 DNA template using the M13 (-40) primer. Sequencing results obtained using the SmartPower 4000 power supply and the CastAway system exhibit crisp, clear bands. Read lengths of approximately 400 bases per gel with double sample loading are routinely achieved (data not shown). The built-in temperature controller of the SmartPower 4000 power supply coupled with the thin, 0.25-mm format of the CastAway precast gels produce sequencing data of superior quality in a fraction of the time required for conventional sequencing methods.2 Due to the temperature controller of the SmartPower power supply, the maximum desired temperature of the gel can be set, eliminating the need for manual gel monitoring. This feature is especially useful when double loading sequencing gels since the longer run time can cause the gel to become hot, and the bands from the second set of samples to become diffuse (data not shown).
figure 3
Horizontal DNA Gel Electrophoresis. In figure 3, the SmartPower 4000 power supply was used for horizontal gel electrophoresis. The pBluescript vector was digested with EcoR I and serially diluted. These samples were loaded onto a 1% agarose gel and electrophoresed for 1.5 hours at 100 volts in 1X TAE buffer using the SmartPower 4000 power supply. Excellent band clarity and resolution were obtained.
figure 4
Vertical Protein Gel Electrophoresis. The SmartPower 4000 power supply was used for protein gel electrophoresis in figure 4, which shows an image of an SDS-PAGE gel run at 130 volts (constant) for 1.5 hours. The SmartPower 4000 power supply has the low wattage control that is necessary to run protein gels. Typically, protein gels require low-wattage conditions (1 to 10 watts) because low-ionic-strength buffers are used.
figure 5
DNA Electroelution. Electroelution is a common technique for purifying DNA, RNA and protein from agarose and polyacrylamide gels. Stratagenes Quik-Pik electroelution capsules (figure 5) are designed for excising and eluting biomolecules from gel polymers. In figure 6, a Kb DNA Ladder molecular weight marker was electrophoresed through a 1% agarose gel in 1X TAE buffer and stained with ethidium bromide. The 2-kb band was excised from the gel and purified using the protocol provided with Quik-Pik electroelution capsules. The purified DNA band fragment was then electrophoresed next to an aliquot of the Kb DNA Ladder marker using the SmartPower 4000 power supply. The conditions for electroelution can be saved as individual files within the SmartPower 4000 power supply and readily recalled for a new experiment.
The SmartPower 4000 power supply is the newest and most innovative power supply available. Many power supplies can maintain either the high-voltage conditions necessary for sequencing gels or the low-voltage conditions necessary for agarose gels. The SmartPower 4000 power supply can handle both of these extremes and anything in between. This versatile power supply has been designed as a single unit that can be used for any electrophoretic application. The broad functionality of the SmartPower power supply makes it ideal for both small and large laboratories.
Blinderman, L., LeSchofs, B., and Sorge, J. (1991) Strategies 4: 22.
Hoener, T., and Drake, D. (1996) Strategies 9: 71-72.
Cayouette, M., and Moores, J. (1996) Strategies 9: 88-89.
* U.S. Patent Nos. 5,055,172 and 5,342,497
** U.S. Patent No. 5,328,581
