Two nitroxide spin probes (7- and 12-doxyl stearic acid) were covalently bonded onto alumina surfaces, and the structures of sodium dodecyl sulfate and poly(acrylic acid) layers adsorbed on them were investigated by monitoring changes in the electron spin resonance spectral characteristics of the probes in comparison to those of electrostatically adsorbed doxyl stearic acid probes. Upon the adsorption of the surfactant and the polymer, the rotational correlation time of the bound probes was found to increase, but Co different extent in different adsorption regions. In contrast, while sodium dodecyl sulfate adsorption caused restriction of motion on the adsorbed probes similar to that on bound ones, the poly(acrylic acid) adsorption produced different effects on spin-spin exchange of the bound and adsorbed probes. The spin-spin exchange peak is proposed to be caused by surface migration and aggregation of the probes resulting from the reduction in available surface sites because of competition by the strongly adsorbing polymer species.