Quantitative Analysis of Digital Gel Images.              Download Program

Introduction.  The Image Processor software provides quantitative analysis of digital gel images. The fluorescence images of the gels stained with fluorescence dye (e.g., Ethidium Bromide) can be acquired utilizing an inexpensive digital camera with a resolution of about 2 Mega Pixels CCD  and interfaced with a personal computer. The software included with the camera package allows for the acquisition of the digital fluorescence images in JPEG format. The JPEG images thus obtained can be analyzed using the Image Processor program.  The Image Processor allows for the selection of a particular lane in the gel, and for the quantitative scanning of the relative fluorescence intensities as a function of distance from the loading wells of the gels, thus revealing the positions of the intercalated DNA bands.

Procedure. Open the JPEG file of the gel image using the Image Processor program. Rotate the gel image if necessary. For further calculations, the gel lanes should be oriented horizontally. Adjust the image contrast to full scale. Select the first gel lane using the cursor lines. Calculate the fluorescence intensity (in arbitrary units) as a function of distance from the loading well of the gel. The computer will automatically display the calculated histogram. Save the histogram in ASCII format. Switch the screen to “Image.”  Select the next lane and repeat the procedure. The histograms can be quantitatively analyzed using any available convenient program such as MS Excel, Corel Quattro Pro, Origin, etc.