880-888Borosilicate glasses with the addition of one of the 3d-transition metals (Ti→Cu) (0.1 g/100g glass) have been investigated as possible materials having bioactivity by infrared reflection spectroscopy and electrical properties after the immersion in simulated body fluid (SPF) for different interval of times. The results show obvious effects of the transition metal ions on the bioactivity of the borosilicate glasses. The results are discussed taking into consideration recent achievements that govern the formation of hydroxyapatite surface layer on glass. Also, IR and electrical results are discussed in relation to the glass composition and structure, which confirm the effect of the formation of HAp layer and the possible mixed ionic and electronic mechanisms due to the addition of transition metal oxides