Jump to main content
Jump to site search


Confocal Raman micro-spectral evidence and physicochemical evaluation of triamterene salts

Abstract

Discrimination of active pharmaceutical ingredients (APIs) existing as neutral molecule or salts is essential and complicated. However, the discrimination of pharmaceutical salts by confocal Raman micro-spectroscopy remains relatively poorly understood. In this paper, four new salts of triamterene (Tri) cocrystallized with nicotinic acid (NA), benzoic acid (BA), p-toluenesulfonic acid (TA), or isonicotinic acid (INA) were prepared and characterized comprehensively with powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), polarized Light Microscopy (PLM), and dynamic vapor sorption (DVS). Ionized pteridine is identified by marker peaks in the confocal Raman micro-spectra that are characteristic of C=N. Tri-NA•H2O and Tri-TA were further demonstrated as ionic salts, of which N1 atom of Tri protonation by single crystal X-ray diffraction (SCXRD). The intrinsic dissolution rate (IDR) and apparent equilibrium solubility of these four salts are improved compared to pure Tri component, especially for Tri-BA. This study provides a valuable insight into the pharmaceutical salts discrimination by vibrational spectra and presents that the Tri with an acid can be a possible and promising alternative formulation of Tri.

Back to tab navigation

Supplementary files

Publication details

The article was received on 15 Aug 2018, accepted on 11 Oct 2018 and first published on 12 Oct 2018


Article type: Paper
DOI: 10.1039/C8AN01579A
Citation: Analyst, 2018, Accepted Manuscript
  •   Request permissions

    Confocal Raman micro-spectral evidence and physicochemical evaluation of triamterene salts

    B. Peng, Z. Zhang, J. Wang, M. Li, Q. Zhang and X. Mei, Analyst, 2018, Accepted Manuscript , DOI: 10.1039/C8AN01579A

Search articles by author

Spotlight

Advertisements