The present invention relates to a method and apparatus for simultaneous
quantification of the amounts of one or more radioactive nuclides within
arbitrary regions on a surface where these nuclides have been deposited,
adsorbed or fixed. These radioactive nuclides serve as markers on
compounds that typically have been incorporated into tissue sections or
into larger biological molecules that by various mechanisms have been
bound to chemical substances on this surface. The method is especially
well suited for DNA microarray deductions through the use of nucleotides
labelled with different beta-emitting radionuclides.