Determination of pK(a) Values of Some Sulfonamides by LC and LC-PDA Methods in Acetonitrile-Water Binary Mixtures


Sanli N., Sanli S., Ozkan G., DENİZLİ A.

JOURNAL OF THE BRAZILIAN CHEMICAL SOCIETY, cilt.21, ss.1952-1960, 2010 (SCI İndekslerine Giren Dergi) identifier

  • Cilt numarası: 21 Konu: 10
  • Basım Tarihi: 2010
  • Dergi Adı: JOURNAL OF THE BRAZILIAN CHEMICAL SOCIETY
  • Sayfa Sayıları: ss.1952-1960

Özet

The dissociation constants of seven sulfonamide antibiotics, sulfadiazine, sulfathiazole, sulfamerazine, sulfamethazine, sulfamonomethoxine, sulfadoxine and sulfamethoxazole, have been determined in different acetonitrile-water binary mixtures (15, 30, 40, 50% v/v) by means of reversed-phase liquid chromatographic data. Also, a method based on the absorbance spectra at the maximum of chromatographic peaks previously obtained has been applied to determine the pK(a) values. This method can be applied to data obtained from LC-UV (photodiode array detection (PDA)) instruments and retains all the advantages of LC and spectrophotometric methods. Linear relationships were observed when the calculated pK(a) values of sulfonamides in different solvent mixtures were plotted against the acetonitrile molar fraction.