1 23 Journal of Sol-Gel Science and Technology ISSN 0928-0707 Volume 61 Number 2 J Sol-Gel Sci Technol (2012) 61:390-402 DOI 10.1007/s10971-011-2639-9 Photocatalytic degradation of metoprolol in water suspension of TiO 2 nanopowders prepared using sol–gel route Maja Šćepanović, Biljana Abramović, Aleksandar Golubović, Sanja Kler, Mirjana Grujić-Brojčin, Zorana Dohčević-Mitrović, Biljana Babić, et al.