Quercetin (3,3 ',4 ',5,7-pentahydroxyflavone) complexes with calcium(II) and magnesium(II), its potentiometric and spectrophotometric studies

Erdogan G., Karadag R.

REVIEWS IN ANALYTICAL CHEMISTRY, cilt.24, sa.1, ss.9-23, 2005 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 24 Sayı: 1
  • Basım Tarihi: 2005
  • Dergi Adı: REVIEWS IN ANALYTICAL CHEMISTRY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.9-23
  • Anahtar Kelimeler: quercetin, magnesium, calcium, stability constant, potentiometri, spectrophotometri, CONSTANTS, PLASMA
  • Marmara Üniversitesi Adresli: Hayır

Özet

In this study, the stability constants of the complexes of quercetin formed with calcium(II) and magnesium(II) were determined potentiometrically by using Calvin-Bjerrum and Irving Rossotti methods and by spectrophotometry. The evaluated protonation constants of the ligand were found: logK(1) = 9.63 +/- 0.11 and logK(2) = 8.32 +/- 013, at the 25 degrees C. For the calcium and magnesium complexes logarithms of the stability constants were found: for Ca : logK = 2.91 +/- 0.04, and for Magnesium: logK = 3.51 +/- 0.07. From the results, the components of quercetin-metal complexes are given 1:1 (quercetin:metal ratio) both Ca(II) and Mg(II).