packing a float into a A8R8G8B8 texture (shader)

Hi guys, I would like to pack a float in the range [0.0..1.0] into an integer texture (A8R8G8B8 format), and also converting the texture value back into a float. I don't want to use a 32F texture. Is that possible? Does anyone have an efficient way of packing/unpacking such a value? I am using HLSL,