Fig. 2.

Advantages of biochips with 3D elements in comparison with 2D elements residing on a planar surface. Molecular complexes formed in 3D elements and distributed uniformly throughout the volume are located in the water-like homogeneous environment of the hydrogel and have identical energies of formation. In this case, the temperature-induced dissociation of such complexes occurs in a narrow temperature range and it is always possible to select a temperature at which the perfect complex remains stable, while the imperfect complex will be substantially dissociated. Therefore, in the case of 3D elements, perfect complexes can be detected by signals exceeding the signals of imperfect complexes several times. In 2D elements, the energy of complex formation is superimposed with different energy interactions between the complexes and the substrate surface. As a result, the dissociation curves of molecular complexes have a gentle slope and the temperature shift (usually 3–4°C) between the curves characterizing the perfect and imperfect complexes is insufficient to provide a significant difference in the corresponding signals