Freeze dried multicomponent inclusion complexes of quercetin: Physicochemical evaluation and pharmacodynamic study

Abstract

The present study was undertaken to investigate the effect of cyclodextrin (CD) complexation in presenceof hydrophilic polymer on physicochemical properties as well as anti- inflammatory activity of quercetin (QUN). Theinitial phase solubility studies were carried out in presence and absence of hydrophilic polymers(hydroxypropylmethylcellulose, polyvinylpyrrolidone K30 and poloxamer 188) to study their effect on the stability andcomplexation efficiency of CDs. The binary (QUN-βCD and QUN-HPβCD) and multicomponent (QUN-βCD-POLOand QUN-HPβCD-POLO) inclusion complexes of QUN prepared using lyophilization technique. The complexes weresubjected to DSC, ATR-FTIR, XRPD and SEM analysis, and evaluated for drug content and saturation solubility. Thephase solubility studies revealed the formation of QUN-βCD and QUN-HPβCD complexes with 1:1 stoichiometry. Theincorporation of POLO increased the stability as well as complexation efficiency of CDs. FTIR and DSC analysisindicated hydrogen bonding interaction POLO with QUN and CDs. XRD and SEM analysis revealed greateramorphization in case of multicomponent inclusion complexes. All complexes showed uniform drug content. QUNHPβCD-POLO exhibited maximum solubility than the physical mixtures and other complexes. The pure QUN andQUN-HPβCD-POLO were tested for in vivo anti-inflammatory activity by Carrageenan induced rat paw edema method.QUN-HPβCD-POLO exhibited significant increase in anti-inflammatory activity as compared to pure QUN.