Investigation on inhibition kinetics and mechanism the evaluation of application possibilities
Küçük Resim Yok
Tarih
2000
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Ege Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Bu çalışmada, Pd(II) tarafından katalizlenen Co(III) EDTA ile hipofosfit iyonu arasındaki tepkime, indikatör tepkime olarak seçilmiştir.Bu katalitik tepkimenin inhibisyon kinetiği hem mekanistik yönden incelenmiş hem de uygulama olanakları araştırılmıştır. İndikatör tepkime için PdCl2'den başka katalizörler de (Pt, Au ve Ni tuzları) denenmiş ve reaksiyon üzerinde etkilerinin olmadığı saptanmıştır. Gerek farklı katalizörlerle yapılan çalışmalar gerekse tepkime değişkenlerinin tepkime hızına olan etkileri üzerindeki ayrıntılı çalışmalar sonucunda orijinal bir tepkime mekanizması önerilmiştir. Tepkime spektrofotometrik olarak izlenmiş ve 540 nm de absorbans değişimi ölçülmüştür. Optimum koşullar altında iyodür, sistin, sistein ve N-asetil sisteinin iz miktarlarının bile tepkime üzerinde güçlü inhibisyon etkileri olduğu gösterilmiştir. İnhibisyon etkilerinden yararlanılarak, bu maddelerin iz miktarlarının belirlenebilme olanakları araştırılmıştır. Yöntem, su, idrar, tuz ve bazı ilaç örneklerinde iyodür tayinine uygulanmış ve modifiye Sandell-Kolthoff yöntemi ile karşılaştırılmıştır. Biyolojik sıvılardaki iyot içeriğinin belirlenmesi, gerek beslenme bozuklukları ve gerekse tiroid hastalıklarının metabolik ve epidemiyolojik çalışmaları yönünden önemlidir. İyot miktarı için önerilen bu yöntemin en büyük avantajı idrar örnekleri için bir ön hazırlık sürecinin olmayışıdır. İnhibisyon kinetiğine dayalı miktar belirtim yöntemi, kolay, hızlı ve ekonomiktir. Bu nedenlerle de araştırıcılar için uygulama alanlarının (kimya, biyokimya, çevre kimyası, eczacılık vb.) daha da geliştirilmesine gerek duyulan, araştırmaya açık bir yöntemdir
In this study, the reaction between Co(III)EDTA and HIPOP, catalyzed by Pd(II) has been chosen as the indicator reaction. The inhibition kinetics of this catalytic reaction has been investigated with a mechanistic approach and, the possibilities of its application have been evaluated. Catalyzers other than PdCl2 ( Pt, Au, Ni salts ) have been assayed for the indicator reaction and it was observed that theese catalysts have no effect on the reaction. Using the results detailed studies on various catalyzers as well as on different variables effecting the reaction rate, an original reaction mechanism is proposed. The reaction was monitored spectrophotometrically and the change in absorbance measured at 540 nm. It was shown that iodide, cystine, cysteine, and N-acetylcysteine, even in trace amounts, had a strong inhibitory effect under optimum conditions. Possibilities of the estimation of trace amounts of these substances based on their inhibitory effects were investigated. The method was applied to the determination of iodide in water, urine, salt, and some drug samples and was compared with the modified Sandell- Kolthoff method. The determination of the iodide content of biological fluids is important both in malnutrition conditions and in the metabolic and epidemiological studies of tyroid diseases. The main advantage of this method proposed for the determination of iodide in urine samples is that it does not necessitate a preparative procedure. The quantitative assay developed, based on inhibition kinetics, is practical, fast, and economical. For this reason, it is a technique open to research for the development of application fields (chemistry, biochemistry, enviromental and pharmaceutical chemistry e.g ) for researchers interested.
In this study, the reaction between Co(III)EDTA and HIPOP, catalyzed by Pd(II) has been chosen as the indicator reaction. The inhibition kinetics of this catalytic reaction has been investigated with a mechanistic approach and, the possibilities of its application have been evaluated. Catalyzers other than PdCl2 ( Pt, Au, Ni salts ) have been assayed for the indicator reaction and it was observed that theese catalysts have no effect on the reaction. Using the results detailed studies on various catalyzers as well as on different variables effecting the reaction rate, an original reaction mechanism is proposed. The reaction was monitored spectrophotometrically and the change in absorbance measured at 540 nm. It was shown that iodide, cystine, cysteine, and N-acetylcysteine, even in trace amounts, had a strong inhibitory effect under optimum conditions. Possibilities of the estimation of trace amounts of these substances based on their inhibitory effects were investigated. The method was applied to the determination of iodide in water, urine, salt, and some drug samples and was compared with the modified Sandell- Kolthoff method. The determination of the iodide content of biological fluids is important both in malnutrition conditions and in the metabolic and epidemiological studies of tyroid diseases. The main advantage of this method proposed for the determination of iodide in urine samples is that it does not necessitate a preparative procedure. The quantitative assay developed, based on inhibition kinetics, is practical, fast, and economical. For this reason, it is a technique open to research for the development of application fields (chemistry, biochemistry, enviromental and pharmaceutical chemistry e.g ) for researchers interested.
Açıklama
Anahtar Kelimeler
Biyokimya, Biochemistry, Kimya, Chemistry
