With the vast number of nucleic acid manipulations that are necessary in biomedical research, it is crucial for a researcher to have a reliable thermal cycler. The GeneAmp® PCR System 9700 from Applied Biosystems thoroughly fulfills this role. It is one of the most versatile and affordable thermal cyclers currently on the market. Although the 96-well block is sufficient for most routine applications such as PCR and sequencing, there are interchangeable blocks with varying well sizes (0.5ml, 96, 384) and metals (aluminum, silver, gold-plated silver) making the system appropriate for a wide variety of applications. The platinum lid reduces sample evaporation thus eliminating the need for a mineral oil overlay. The GeneAmp® PCR System 9700 is also is accurate to the tenth decimal place to accommodate the demands of sensitive templates.
In terms of its on screen display, this machine has several small perks that allow the user to quickly become comfortable using it. The screen is blue with white text, which adds to the visibility of the characters. Display prompts are managed by 5 function keys that are beneath the corresponding position on the screen. To assist with determining the necessary temperatures for various cycles, this instrument has an on screen melting temperature (Tm) calculator. By means of this display, every option is editable including the number of temperature changes per cycle and the number of holds. These attributes are graphically portrayed by a series of lines. The temperature of each cycle is listed above the solid, horizontal line and the position of this line varies along with the change of temperature. Secondly, there are a series of vertical, dashed lines separating the initial hold, the experimental cycles, and any subsequent holds. The appropriate portion of the line and the temperature listed above blink to show the progress of the cycle. During the cycles, the instrument will automatically read out the statistics of the run, such as when it began and what time it is expected to end.
Another valuable attribute of this machine is the memory. It is possible to store up to 100 protocols and you can sort them by file name, date entered, or size of the protocol. This makes it possible to quickly locate frequently used protocols and start the run, thus eliminating time wasted in reprogramming old methods. The memory card is also transportable to other machines.
The only remotely derogatory statement I can make regarding thisintrument is that Applied Biosystems currently advertises a 9800 model that has a slightly faster ramp speed.
In conclusion, I assert that the GeneAmp® PCR System 9700 is the most versatile, yet affordable thermal cycler available on the market. It is rare for laboratory instrumentation to be intuitive to operate, but this thermal cycler accomplishes this while securing its position as a reliable and accurate means of manipulating nucleic acids.
Enjoli Cooke
Research Fellow
National Institutes of Health
National Eye Institute