The DNA Engine Opticon System (PTC-200 DNA Engine Cycler and CFD-3200 Opticon Detector) is an easy-to-use and sensitive machine for measuring continuous fluorescence, particularly in real-time quantitative PCR (qPCR) applications. The detector itself is available as a complete system (including a desktop computer, monitor, and DNA engine thermal cycler) or as an upgrade to an existing thermal cycler. This system has an excitation range of 450-495 nm and a detection range of 515-545 nm. It has a heated lid which eliminates the need for oil on top of samples and samples can be run in either 96-well plates or strip tubes. It has a temperature range of 0 to 150°C with an accuracy of ±0.3°C and a relatively quick ramping speed: up to 3°C per second. A temperature gradient feature is available that allows the user to easily optimize the annealing temperature of the PCR reaction by running each column of wells at a separate temperature. A gradient calculator is built into the software which makes it very easy to calculate the well temperature across all 12 columns. The Opticon is compatible with many different chemistries including SYBR® Green I, Molecular Beacons, TaqMan® Probes, Scorpion® Probes, and the Amplifluor® System.
The software associated with the Opticon System is fairly simple to use as it is divided into three stages: experimental setup and programming, run initiation and status, and data analysis. Protocols are easily edited and saved using pull-down menus. A nice feature of this software is the quick-load application that allows users to repeatedly load and use the same saved experimental protocol without having to set it up every time. Using the initiation and status portion of the software allows the user to monitor which step is currently running, how much time is left in the run, and the current temperature of the sample and the lid. The data analysis stage generates graphs and plots data in very easy to understand formats and allows for easy adjustment of threshold values. Graphs can be made using fluorescence versus cycle number, log quantity versus threshold cycle, or both.
MJ Research, the original manufacturer of the DNA Engine Opticon System, has been purchased by Bio-Rad who now sells and supports this system. This transition rendered technical support virtually non-existent for quite some time due to a court injunction involving PCR patents. However, the injunction has now been lifted and customer support by Bio-Rad is excellent. In fact, they extended the length of the warranty for this machine by the amount of months that customer service was unavailable.
I have used this machine for the past two years in our lab quite extensively to quantify HIF-1-alpha using both SYBR® Green I and TaqMan® probe chemistries with much success. Once the experimental conditions are optimized, the quick load feature of the software and the high temperature ramping rate make running samples much quicker than many real-time PCR machines.