Ultimate spatial resolution in boron delta-doped homoepitaxial diamond interfaces has been achieved by diffraction contrast technique in Transmission Electron Microscopy. The combination of two reflections with the Howie-Whelan equations allows profiling the boron content of delta-doped diamond homoepitaxial layers by fitting experimentally measured CTEM intensities with the theoretical ones. To validate the method, the obtained doping profiles are compared with that of secondary ion mass spectrometry, obtaining a boron concentration of 1.6.10(21) at/cm(-3), which is in good agreement with that of SIMS. This approach is capable to perform dopant concentration quantification in a non-destructive way, and provides the possibility of nanometric resolution dopant concentration mapping by TEM.