title: EPR Studies of DOPA-Melanin Complexes with Netilmicin and Cu(II) at Temperatures in the Range of 105-300 K.
abstract: The application of electron paramagnetic resonance (EPR) spectroscopy in pharmacy of melanin complexes with netilmicin and Cu(II) was presented. The continuous microwave saturation of EPR spectra of DOPA-melanin and the complexes was performed. EPR spectra were measured on an X-band (9.3 GHz) spectrometer at temperatures in the range of 105-300 K. Paramagnetic copper ions decrease the intensity of the EPR lines of melanin's free radicals. It was found that fast spin-lattice relaxation characterizes DOPA-melanin-Cu(II) complexes. Slow spin-lattice relaxation processes exist in melanin's paramagnetic centers of DOPA-melanin and DOPA-melanin-netilmicin, [DOPA-melanin-netilmicin]-Cu(II), [DOPA-melanin-Cu(II)]-netilmicin complexes. Spin-lattice relaxation processes are faster at higher temperatures. The homogeneous broadening of EPR lines for melanin complexes was observed. The practical consequences of differences between paramagnetic properties of melanin complexes with netilmicin and the complexes with Cu(II) were discussed.
authors.affiliation: Division of Laboratory Medicine, Department of Biophysics, School of Pharmacy, Medical University of Silesia in Katowice, Jedności 8, 41-200 Sosnowiec, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Zdybel
authors.forename: Barbara
authors.initials: B
authors.lastname: Pilawa
authors.forename: Ewa
authors.initials: E
authors.lastname: Buszman
authors.forename: Dorota
authors.initials: D
authors.lastname: Wrześniok
authors.forename: Ryszard
authors.initials: R
authors.lastname: Krzyminiewski
authors.forename: Zdzisław
authors.initials: Z
authors.lastname: Kruczyński