Tuning the pKa of the antihistaminic drug chlorpheniramine maleate by supramolecular interactions with water-soluble polymers

Ignacio Moreno-Villoslada, Felipe González, Bernabé L. Rivas, Toshimichi Shibue, Hiroyuki Nishide

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37 Citations (Scopus)


The interaction of the pharmacologically important chlorpheniramine maleate (CPM) with polyanions containing sulfonate groups such as poly(sodium 4-styrenesulfonate) (PSS), poly(sodium vinylsulfonate) (PVS), and the more hydrophobic poly(sodium 2-(N-acrylamido)-2-methyl-propanesulfonate) (PAMPS) has been studied by 1H NMR. It was found that the pKa of the low-molecular weight molecule (LMWM) may be modified by its interaction with the polyanions, changing from 3 to 5, due to electric charge compensation. Interestingly, the interaction of CPM with PSS produces changes in CPM resonances, such as a general broadening and upfield shifts of the signals, and NOE effects between the LMWM and the water-soluble polymer (WSP) that indicate the presence of π-π interactions.

Original languageEnglish
Pages (from-to)799-804
Number of pages6
Issue number3
Publication statusPublished - 2007 Jan 26



  • π-π interactions
  • Chlorpheniramine maleate
  • Water-soluble polymers

ASJC Scopus subject areas

  • Organic Chemistry
  • Polymers and Plastics

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