Electron paramagnetic resonance studies of free radicals: The research legacy of Janko N. Herak
By: Erim Bešić, Valerije Vrček and Davor Šakić
References
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- J. N. Herak, K. Adamič and J. Blinc, Electron spin resonance study of irradiated anhydrous maltose, J. Chem. Phys. 42(7) (1965) 2388–2391; https://doi.org/10.1063/1.1696305
- J. N. Herak and W. Gordy, Hydrogen addition radicals on RNA and nucleic acid bases at 77 oK, Proc. Natl. Acad. Sci. USA 55(6) (1966) 1373–1378; https://doi.org/10.1073/pnas.55.6.137
- J. N. Herak and W. Gordy, ESR study of nucleosides and nucleotides bombarded with hydrogen atoms, Proc. Natl. Acad. Sci. USA 56(1) (1966) 7–11; https://doi.org/10.1073/pnas.56.1.7
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- J. N. Herak and W. Gordy, Electron spin resonance study of hydrogen-addition and -replacement reactions in some pyrimidine compounds, J. Am. Chem. Soc. 89(15) (1967) 3818–3821; https://doi.org/10.1021/ja00991a024
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- J. N. Herak, EPR study of radiation damage of deuterated single crystal of thymidine, J. Chem. Phys. 52(11) (1970) 6440–6441; https://doi.org/10.1063/1.1672972
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- J. N. Herak and G. Schoffa, E.P.R. spectroscopy of radicals formed in a single crystal of 6-azathy-mine by irradiation, Mol. Phys. 22(2) (1971) 379–383; https://doi.org/10.1080/00268977100102671
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- A. Dulčić and J. N. Herak, Radiation-induced pair-wise radical formation in single crystals of thy-mine, Biochim. Biophys. Acta 319(2) (1973) 109–115; https://doi.org/10.1016/0005-2787(73)90001-4
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- J. N. Herak and C. A. McDowell, ENDOR study of long-range spin interactions in molecular crystals. I. 1-methyl uracil, J. Chem. Phys. 61(3) (1974) 1129–1135; https://doi.org/10.1063/1.1681985
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- D. Krilov and J. N. Herak, ESR evidence for the radiation-induced breakage of the sugar-phosphate bonds in nucleotides: Single crystal of deoxycytidine 5’-monophosphate, Biochim. Biophys. Acta 366(4) (1974) 396–401; https://doi.org/10.1016/0005-2787(74)90037-9
- J. N. Herak, D. Krilov and C. A. McDowell, ENDOR study of the stable radicals in g- or X-ray-irradiated single crystal of deoxycytidine-5’-phosphate, J. Magn. Reson. (1976) 23(1) (1976) 1–7; https://doi.org/10.1016/0022-2364(76)90131-1
- J. N. Herak and B. Rakvin, Electron paramagnetic resonance of superparamagnetic NiO particles, Phys. Lett. A 53(4) (1975) 307–309; https://doi.org/10.1016/0375-9601(75)90079-1
- B. Rakvin and J. N. Herak, Proton magnetic resonance parameters of hydroxyl groups on silica gel, Surf. Sci. A 51(1) (1975) 310–312; https://doi.org/10.1016/0039-6028(75)90255-1
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- B. Rakvin and J. N. Herak, The NO2 species in an irradiated single crystal of uridine 5’-phosphate (Na salt) – An ESR study, Radiat. Res. 78(3) (1979) 550–553; https://doi.org/10.2307/3574980
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- G. Pifat, J. Brnjas-Kraljevic, J. N. Herak, G. Jürgens and A. Holasek, Proton relaxation study of molecular motions in low-density lipoproteins, Int. J. Biol. Macromol. 3(5) (1981) 282–286; https://doi.org/10.1016/0141-8130(81)90043-X
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- J. N. Herak, G. Pifat, J. Brnjas-Kraljević, G. Knipping and A. Holasek, Probing of the porcine serum lipoprotein surfaces by Mn(II) binding: An e.s.r. study, Int. J. Biol. Macromol. 5(4) (1983) 233–236; https://doi.org/10.1016/0141-8130(83)90008-9
- D. Krilov, G. Pifat and J. N. Herak, Electron spin resonance spin-trapping study of peroxidation of human low density lipoprotein, Can. J. Chem. 66(8) (1988) 1957–1960; https://doi.org/10.1139/v88-315
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- J. N. Herak, Oxidation hypothesis of atherogenesis, Acta Pharm. Jugosl. 41 (1991) 299–309.
- J. N. Herak, N. Stojanović and D. Krilov, 3.P.65 Slow autoxidation of LDL spares alpha-tocopherol, Atherosclerosis 134(1) (1997) 212–212; Abstract – 11th International Symposium on Atherosclerosis, Paris, 5–9 October 1997; https://doi.org/10.1016/S0021-9150(97)89094-6
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- J. N. Herak, N. Stojanović and D. Krilov, Probabilistic kinetic model of slow oxidation of low-density lipoprotein: I. Theory, Chem. Phys. Lipids 129(1) (2004) 63–74; https://doi.org/10.1016/j.chemphyslip.2003.12.001
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- J. N. Herak, K. Sanković, D. Krilov and J. Hüttermann, An EPR study of the transfer and trapping of holes produced by radiation in guanine (thioguanine) hydrochloride single crystals, Radiat. Res. 151(3) (1999) 319–324; https://doi.org/10.2307/3579944
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- D. Krilov, A. Lekić, E. Bešić and J. N. Herak, EPR study of a copper center in a single crystal of cyto-sine monohydrate, J. Inorg. Biochem. 99(3) (2005) 886–889; https://doi.org/10.1016/j.jinorgbio.2005.01.001
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- E. Bešić and D. Šakić, EPR study of a copper impurity center in a single crystal of 6-chlorouracil, J. Mol. Struct. 1321(3) (2025) Article ID 140080 (9 pages); https://doi.org/10.1016/j.molstruc.2024.140080
- V. Gomzi and J. N. Herak, Density functional theory investigation of the proton hyperfine couplings in thiocytosine oxidation product in the cytosine monohydrate crystal lattice, J. Mol. Struct. – THEOCHEM 629(1-3) (2003) 71–76; https://doi.org/10.1016/S0166-1280(03)00128-3
- V. Gomzi and J. N. Herak, Ionization potentials of nucleobase analogs using partial third-order electron propagator method, J. Mol. Struct. – THEOCHEM 683(1–3) (2004) 155–157; https://doi.org/10.1016/j.theochem.2004.07.005
- V. Gomzi and J. N. Herak, Dependence of the radical g-tensor on the molecular environment. Sulfur-centered radicals of thiocytosine in the cytosine crystal matrices, Chem. Phys. 333(2–3) (2007) 112–118; https://doi.org/10.1016/j.chemphys.2007.01.010
Language: English
Page range: 1 - 22
Accepted on: May 12, 2026
Published on: Jun 30, 2026
Published by: Croatian Pharmaceutical Society
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