Organik, inorganik ve biyoorganik maddelerde elektron spin rezonans (ESR) uygulamaları
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Dosyalar
Tarih
2010
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Selçuk Üniversitesi Fen Bilimleri Enstitüsü
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Bu tez çalışmasında biyolojik ve tıbbi öneme sahip bazı maddeler tek kristal haline getirilerek Elektron Spin Rezonans (ESR) yöntemiyle incelenmiştir. Elde edilen tek kristaller oda sıcaklığında ışınlarına maruz bırakılarak 123-450K sıcaklık aralığında ve her bir kristalin birbirine dik üç ekseninde 0o-180o açıları arasında 10 derecelik aralıklarla çevrilerek Bruker EMX-081 ESR spektrometresi ile spektrumları alınmıştır. Spektrumlardan elde edilen veriler ve maddelerin kimyasal yapıları göz önüne alınarak ışınlanmış tek kristallerde oluşan radikaller tespit edilmiş ve bu radikallere ait ESR parametreleri belirlenmiştir. Bir quinone türevi olan ışınlanmış 3,5-di-tert-butyl-1,2-benzoquinone (DTBQ) tek kristalinde veya radikali olduğu tespit edilmiştir. Ayrıca yalnızca bazı yönelimlerde radikaline rastlanmıştır. Bir üre türevi olan 4-phenylsemicarbazide (4PSC) tek kristalinde biçimine radikali oluştuğu anlaşılmıştır. Bir antioksidan olan 2,5-di-tert-butyl-hydroquinone (DTBHQ) tek kristalinde phenyl halkasındaki OH hidrojenlerinden birinin kopması nedeniyle hydoquinone anyon radikali oluştuğu ve yine bir antioksidan olan oksim türevi 2,2,4,4-tetramethyl-3-pentanone-oxime (TPO) tek kristalinde maddenin konformasyonel izomerlerinden gelen iki benzer iminoksi radikali ( ) olduğu tespit edilmiştir. Bir kolesterol esteri olan cholesteryl chloride tek kristalinde ve radikali oluştuğu anlaşılmıştır. Radikallere ait spektroskopik yarılma faktörü ve aşırı ince yapı sabitleri deneysel veriler kullanılarak en küçük kareler yöntemiyle ve doğrultu kosinüsleri bilgisayar programı yardımı ile hesaplanmıştır. Ayrıca deneysel olarak gözlenen spektrumlar simulasyon programı kullanılarak çizdirilmiş ve deneysel spektrumlarla tam bir uyum içinde olduğu gözlenmiştir.
In this thesis, some samples that have biological and medical importance were single crystallized and investigated by Electron Spin Resonance (ESR) technique. The grown single crystals were irradiated by rays then ESR spectra were detected by a Bruker EMX-081 ESR spectrometer at 123-450K temperature range, along three perpendicular axes rotating 0o-180o angles with 10o steps. The ESR parameters of the radicals produced in the samples have been determined by considering the ESR spectra and the chemical structure of the samples. In 3,5-di-tert-butyl-1,2-benzoquinone (DTBQ) single crystal which is a quinone derivative or radical has been determined. Besides these radicals radical has also been observed in some orientations. In an urea derivative 4-phenylsemicarbazide (4PSC) single crystal pi-radical has been determined. In an antioxidant 2,5-di-tert-butylhydroquinone (DTBHQ) single crystal hydroquinone anion radical has been determined to be product of the breaking off OH hydrogen in the phenyl ring. In an another antioxidant 2,2,4,4-tetramethyl-3-pentanone oxime (TPO) single crystal two similar iminoxy radicals ( ) have been determined which come out from conformational isomers. In a cholesteryl ester cholesteryl chloride single crystal and radicals have been determined.The hyperfine coupling constants, spectroscopic splitting factors and direction cosines belonging to them have been calculated using experimental values and the method of least squares by a computer program. Besides, the spectra observed experimentally have been tested by using a simulation program and the experimental spectra observed to be in good agreement with the theoretical values.
In this thesis, some samples that have biological and medical importance were single crystallized and investigated by Electron Spin Resonance (ESR) technique. The grown single crystals were irradiated by rays then ESR spectra were detected by a Bruker EMX-081 ESR spectrometer at 123-450K temperature range, along three perpendicular axes rotating 0o-180o angles with 10o steps. The ESR parameters of the radicals produced in the samples have been determined by considering the ESR spectra and the chemical structure of the samples. In 3,5-di-tert-butyl-1,2-benzoquinone (DTBQ) single crystal which is a quinone derivative or radical has been determined. Besides these radicals radical has also been observed in some orientations. In an urea derivative 4-phenylsemicarbazide (4PSC) single crystal pi-radical has been determined. In an antioxidant 2,5-di-tert-butylhydroquinone (DTBHQ) single crystal hydroquinone anion radical has been determined to be product of the breaking off OH hydrogen in the phenyl ring. In an another antioxidant 2,2,4,4-tetramethyl-3-pentanone oxime (TPO) single crystal two similar iminoxy radicals ( ) have been determined which come out from conformational isomers. In a cholesteryl ester cholesteryl chloride single crystal and radicals have been determined.The hyperfine coupling constants, spectroscopic splitting factors and direction cosines belonging to them have been calculated using experimental values and the method of least squares by a computer program. Besides, the spectra observed experimentally have been tested by using a simulation program and the experimental spectra observed to be in good agreement with the theoretical values.
Açıklama
Anahtar Kelimeler
Elektron spin rezonans, Electron spin resonance, Serbest radikal, Free radical, Spektroskopik yarılma faktörü, Spectroscopic splitting factor
Kaynak
WoS Q Değeri
Scopus Q Değeri
Cilt
Sayı
Künye
Sayın, Ü. (2010). Organik, inorganik ve biyoorganik maddelerde elektron spin rezonans (ESR) uygulamaları. Selçuk Üniversitesi, Yayımlanmış doktora tezi, Konya.
