Electronic absorption spectra of polyaniline (PANI) solutions in a transparent cell were observed to change as the cell gap was reduced to similar to 10 mum. Although the cell gap size was wide enough, at least two orders of magnitude larger than the polymer coils in the solution, the observed;changes were explained by self-confinement of polymer molecules at the liquid/solid interface as a result of their intense adsorption and depletion of the relatively small solution volume, respectively. It was shown that the cell material affects electronic spectra of confined polymer solutions.