Catalase could be dissolved in a range of organic solvents by modifying less than 5% of its surface amino groups with a reactive nonionic surfactant derivative, bis(brij35). A solution of brij35-modified catalase in I,I,1-trichloroethylene displayed substantially greater activity than PEG modified enzyme. Modification of the enzyme surface with brij35 may facilitate enzyme solution through the formation of small enzyme aggregates enclosed within a reverse micelle formed from free and covalently bound brij35.