Data documentation is one the most important parts of research. A good quality image is essential for analysis of results, presentations and publications. Documentation of gel photographs is one rigorously used methodology for analysis. Hence, there are plenty of gel documentation systems available from different companies, however, in my view, UVP is one of the most trusted and economical brands.
The EC2 Darkroom from UVP is a basic requirement for any laboratory. The primary importance of a darkroom is that it helps in avoiding exposure to UV radiation. The darkroom consists of a transilluminator on a sliding tray for ease of handling and documenting gels; there is also a CCD camera on top. There are three knobs for directing the transmission of different light: The first knob allows the selection of UV light (254nm/365nm) or white light, the second knob is a filter wheel selector and the third knob is for transilluminator control. The darkroom also has a master on/off switch for light. With the help of a window (gel viewer), one can easily view gels without getting exposed to UV light.
There are different options for the visualization of gels. The filter wheel contains 5 filters for visualizing gels stained with Comassie blue, SYBR® Green, SYBR® Gold, Nile Red or ethidium bromide. The transilluminator control knob helps in safe usage (i.e. eliminating the risk of exposure to UV). It has three options: First is a safety switch which automatically switches off the UV light when the door is open. The second is “Always Off” which can be used when one wants to capture a chemiluminescent image. The third is “Always On” which can be used when cutting gels or removing a gel piece containing DNA or protein.
UVP also provides an optional “LabWorks Image Acquisition and Analysis Software” package for documentation and analysis of Western blots as well as RNA or DNA agarose gels. Coomassie and Nile Red stains can also be documented and analyzed. Colony counting is easier with the help of LabWorks. Intensity measurements for normalization and elucidating the levels of molecular alterations can also be performed. The software can also be used for assignment of molecular weights to unknown proteins; in addition, one can estimate protein amount if the proper standards are used.
We use the EC2 Darkroom from UVP as an all-purpose (i.e. for DNA, RNA, protein gels) system in our research. My work involves the identification of molecular alterations of different proteins and their mRNA at various stages of carcinogenesis. We are interested in investigating levels of different cytoskeletal and associated proteins in order to use them as markers for the progression of cancer. Hence, the accurate measurement of protein levels is extremely important. The presence/absence/level of certain RNA species using RT-PCR has also been analyzed using the LabWorks software. In the case of DNA agarose gels, there is an integration feature which allows you to combine several images/exposures; this has proven excellent for visualization of bands which are difficult to visualize with naked eye. The system also generates good images on thermal paper for better representation of results.
However, there are certain difficulties in measuring intensity at times. For example, for Western blot analysis of relative expression levels of a protein band, one has to manually select the area and cut paste each area of the box for measuring the intensity. Also, in assigning the molecular weight, one has to do much of work manually and the software is not very user-friendly.
This instrument was procured more than 5 years ago and has required little maintenance with only the door knob being in a little bad condition because of rigorous usage. For all analyses, we found the EC2 Darkroom to be convenient and cost-effective and I always recommend this instrument to my colleagues and mention that it’s a worthwhile investment.