{"title":"On Polymeric Gold(I) Complexes with Glutathione in Aqueous Solutions","authors":"I. V. Mironov, V. Yu. Kharlamova","doi":"10.1134/S0036023624601247","DOIUrl":null,"url":null,"abstract":"<p>The study addresses reactions involving gold(I) glutathione complexes in aqueous solutions at <i>T</i> = 25°C and <i>I</i> = 0.2 M (NaCl) in the pH range of 7.20–6.06 (<i>C</i><sub>Au</sub> = (5–10) × 10<sup>–4</sup> M). Using mass spectrometry, it was shown that at <i>C</i><sub>GS</sub> > <i>C</i><sub>Au</sub>, polymeric species <span>\\({\\text{A}}{{{\\text{u}}}_{{\\text{4}}}}({\\text{GS}})_{4}^{*}\\)</span> and <span>\\({\\text{A}}{{{\\text{u}}}_{n}}({\\text{GS}})_{{n + 1}}^{*}\\)</span>, where <i>n</i> ≤ 4, can exist, together with monomeric <span>\\({\\text{Au}}({\\text{GS}})_{2}^{*}\\)</span> (the symbol * means the sum of species with different degrees of protonation). According to UV spectroscopy data, in the range of 0.5 < <i>C</i><sub>GS</sub>/<i>C</i><sub>Au</sub> < 3, all spectra can be described, within the experimental error, as linear combinations of the spectra of four species, including <span>\\({\\text{Au}}({\\text{GS}})_{2}^{*}\\)</span>. The proportion of <span>\\({\\text{Au}}({\\text{GS}})_{2}^{*}\\)</span> decreases with decreasing pH. The equilibrium constant for 0.25 <span>\\({\\text{A}}{{{\\text{u}}}_{{\\text{4}}}}({\\text{GSH}})_{4}^{{4 - }}\\)</span> + <span>\\({\\text{GSH}}_{2}^{ - }\\)</span> = <span>\\({\\text{Au}}({\\text{GSH}})_{2}^{{3 - }}\\)</span> + H<sup>+</sup> amounts to log <i>K</i> = –4.4 ± 0.1 (<i>I</i> = 0.2 M, NaCl).</p>","PeriodicalId":762,"journal":{"name":"Russian Journal of Inorganic Chemistry","volume":"69 10","pages":"1567 - 1574"},"PeriodicalIF":1.8000,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Russian Journal of Inorganic Chemistry","FirstCategoryId":"92","ListUrlMain":"https://link.springer.com/article/10.1134/S0036023624601247","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, INORGANIC & NUCLEAR","Score":null,"Total":0}
引用次数: 0
Abstract
The study addresses reactions involving gold(I) glutathione complexes in aqueous solutions at T = 25°C and I = 0.2 M (NaCl) in the pH range of 7.20–6.06 (CAu = (5–10) × 10–4 M). Using mass spectrometry, it was shown that at CGS > CAu, polymeric species \({\text{A}}{{{\text{u}}}_{{\text{4}}}}({\text{GS}})_{4}^{*}\) and \({\text{A}}{{{\text{u}}}_{n}}({\text{GS}})_{{n + 1}}^{*}\), where n ≤ 4, can exist, together with monomeric \({\text{Au}}({\text{GS}})_{2}^{*}\) (the symbol * means the sum of species with different degrees of protonation). According to UV spectroscopy data, in the range of 0.5 < CGS/CAu < 3, all spectra can be described, within the experimental error, as linear combinations of the spectra of four species, including \({\text{Au}}({\text{GS}})_{2}^{*}\). The proportion of \({\text{Au}}({\text{GS}})_{2}^{*}\) decreases with decreasing pH. The equilibrium constant for 0.25 \({\text{A}}{{{\text{u}}}_{{\text{4}}}}({\text{GSH}})_{4}^{{4 - }}\) + \({\text{GSH}}_{2}^{ - }\) = \({\text{Au}}({\text{GSH}})_{2}^{{3 - }}\) + H+ amounts to log K = –4.4 ± 0.1 (I = 0.2 M, NaCl).
期刊介绍:
Russian Journal of Inorganic Chemistry is a monthly periodical that covers the following topics of research: the synthesis and properties of inorganic compounds, coordination compounds, physicochemical analysis of inorganic systems, theoretical inorganic chemistry, physical methods of investigation, chemistry of solutions, inorganic materials, and nanomaterials.