Optical reflectometry is applied as a tool for studying single and simultaneous adsorption of a carbohydrate, a nonionic surfactant, and a protein, For the nonionic surfactant poly(ethylene oxide) alkyl ether on a silica surface the adsorption process is fast and reversible, and the maximum adsorbed amount was 2.45 mg•m-2. Also, the effect of pH on the adsorption of chitosan on silica, and its interaction with C12EO5 have been studied. The maximum adsorbed amount was obtained for pH ≥6.8 (0.80 mg•m-2). Changes in surface functionality upon adsorbing C12EO5 on a chitosan layer and the protein, bovine serum albumin, are reported. The results are discussed in terms of adsorption kinetics, adsorbed mass plateau values, and reversibility of layer formation.