The new synthesis route to δ-FeOOH (feroxyhyte) was reported.
γ-irradiation of Fe(III) precursor in the presence of amino-dextran produced δ-FeOOH.
In highly reducing and alkaline conditions the Fe(III) reduced to Fe(II).
The rather uniform δ-FeOOH disc-like regular magnetic nanoparticles were formed.