Investigation of non-covalent complex formation between 2-(4-hydroxyphenylazo) benzoic acid and α-Cyclodextrin in solid and solution forms

Abstract

Benzoic acid and its derivatives molecules have some biological properties such as antifungal and antimicrobial properties and so these molecules have been especially used in drug industry. In this study, complex formation between alpha cyclodextrin which is a good drug delivery system and 2-(4-hydroxyphenylazo) benzoic acid was performed in both aqueous environment and solid state form. 2-(4-hydroxyphenylazo) benzoic acid, alpha cyclodextrin and 2-(4-hydroxyphenylazo) benzoic acid / alpha cyclodextrin complex were characterized with UV–Vis, FT-IR, NMR, TGA and powder XRD. Experimental results are clear that alpha cyclodextrin is good carrier system for 2-(4-hydroxyphenylazo) benzoic acid molecule. In solid form, complex formation was indicated using FT-IR and powder XRD. In solution phase, it has been shown by UV–Vis and NMR that complex formation between alpha cyclodextrin and 2-(4-hydroxyphenylazo) benzoic acid molecule was successfully performed. Moreover, according to TGA results, thermal stability of alpha cyclodextrin /2-(4-hydroxyphenylazo) benzoic acid complex was increased.