Tropical Journal of Pharmaceutical Research

Original Research Article | OPEN ACCESS

Characterization, stability and solubility of co-amorphous systems of glibenclamide and L-arginine at different pH

Salma O Aragón-Aburto^1,2, Karina Mondragon-Vasquez¹, Gerardo Valerio-Alfaro², Jorge O Dominguez-Chavez¹

¹Facultad de Bioanalisis Región Veracruz, Universidad Veracruzana, Agustín de Iturbide, 91700, Mexico; ²UNIDA, Tecnologico Nacional de Mexico-IT Veracruz, Miguel A. de Quevedo 2779, 91860, Veracruz, Mexico.

For correspondence:- Jorge Dominguez-Chavez Email: jorgedominguez@uv.mx

Accepted: 23 June 2022 Published: 31 July 2022

Citation: Aragón-Aburto SO, Mondragon-Vasquez K, Valerio-Alfaro G, Dominguez-Chavez JO. Characterization, stability and solubility of co-amorphous systems of glibenclamide and L-arginine at different pH. Trop J Pharm Res 2022; 21(7):1355-1364 doi: 10.4314/tjpr.v21i7.1

© 2022 The authors.
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Abstract

Purpose: To investigate the stability and solubility of co-amorphous systems of glibenclamide (GBC) with L-arginine (L-Arg) at different pH values.

Methods: Three co-amorphous solids of GBC and L-Arg were obtained by fast solvent evaporation using 2:1, 1:1 and 1:2 stoichiometries. All co-amorphous systems were characterized by XRPD, FTIR, RAMAN and NMR-solid state as well as thermal techniques such as DSC and TGA. The stability of co-amorphous systems was evaluated by indicative stability and stability in relevant physiological media was measured at different pH values.

Results: The chemical characterization suggest that there was no proton transference between L-Arg and GBC indicative of co-amorphous solids. Stability studies showed that all the co-amorphous solids are unstable under humid conditions and only the co-amorphous system of GBC: L-Arg 1:2 was stable in all the pH values tested. Solubility studies at different pH values showed that the co-amorphous GBC: L-Arg 1:1 and 1:2, showed increasing solubility values even at pH < 7 (0.6468 mg/mL at pH 1.2 for co-amorphous GBC: L-Arg 1:2 at the first hour) where free GBC was not soluble.

Conclusion: Co-amorphous systems of GBC and L-Arg, is an interesting strategy to increase the solubility of poorly-soluble drugs at acidic pH values

Keywords: Co-amorphous, Glibenclamide, L-Arginine, Solubility, Stability