Sequence-specificity of binding of ribonuclease binase to oligodeoxyribonucleotides immobilized in biochip gel pads was studied. Binding constants for the complexes between binase and selected oligonucleotides were measured. Oligodeoxyribonucleotides GAGAGAG and GAGAGAGAG were found to be high-specific in interaction with binase. These oligonucleotides were used as molecular probes for immobilization in a sorptive medium for subsequent isolation and concentrating of binase from diluted water solutions. Volume capacity of the developed sorptive mediums containing immobilized oligodeoxyribonucleotides GAGAGAG and GAGAGAGAG was found to be 2.6 and 2.3 mg of binase per 1 mL of sorbate correspondingly. After the procedure of affinity chromatography and elution ofbinase from sorptive medium the protein showed the same affinity of binding to oligonucleotides as the initial sample.