This site contains: mathematics courses and book; covers: image analysis, data analysis, and discrete modelling; provides: image analysis software. Created and run by Peter Saveliev.

# Counting stained DNA

Q: we need to "count cell/dna etc from still microscopic image... Here we stained DNA ...S-phase are in red and G-phase is in Blue. We want to count how many red are there and how many blue are there."

I used Pixcavator and did a bit of experimenting with the first image. The red cells are easy to capture - in the red channel, 71 total.

Now the red cells are so bright that in the blue channel they are also present. So, here you see both red and blue and have to subtract:

 299 - 71 = 228 of the blue ones.


Using subtraction here isn't a perfect solution clearly. To separate red and blue one might try to filter the spots based on the size or intensity.

Image processing can help too - I simply removed the red using Photoshop Elements.

The total was 204:

One day you'll be able to use the true color analysis.