ISSN:
1572-901X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Summary The formation constants of species formed in the systems H+-Zn2+-cysteine and H+-Zn2+-cystine have been determined in aqueous solution at 37° and I = 0.15 mot dm−3 (NaClO4), using the pH-metric method. The existence of the following species [ZnL], [ZnL2], [ZnL2H] and [Zn2L3] (2.3 ≤pH ≤ 7.7) was proved for the Zn2+-cysteine system, whereas for the Zn2+-cystine [Zn2L] (5.3 ≤ pH ≤ 6.4) was the only species found. In the Zn2+-cystine system the pH range was severely restricted because of precipitation occurring at pH 〉 6.4. A new experimental and numerical approach was employed in order to implement the possibility of rigorously selecting the species present in each system. The results have been compared with data previously reported on the same systems, considering in particular the different sets of species found in the various works.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01396942
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