Spin-echo small-angle neutron scattering (SESANS) technique is a method to measure the correlation function of the structural organization of materials from nano- to micrometer length scales. As this method does not require neither highly collimated beams nor high incident intensity it can be easily and effectively used at the low flux sources, such as compact accelerator driven neutron sources. Here we describe an important science case for SESANS setup designed at the compact neutron source DARIA. It was shown that SESANS method is a sensitive tool to study the packaging of DNA in the nuclei of biological cells. The sensitivity of the SESANS signal crucially depends on the neutron wavelength. The pulse character of the compact neutron source suits ideally to these investigations as it implies changeable neutron wavelength in the range from 0.2 to 1.0 nm. Such option allows one to study in great detail the internal structure of the biological cell in the length scale from 100 nm to 10 mkm.