Curcumin solid dispersion based on three model acrylic polymers: formulation and release properties

Shuai Zong,Ming Ye,Jinglei Li,Hyun Jin Park,Yuting Liu

doi:10.1590/s2175-97902022e18946

Abstract

To investigate structure-property relationship of polymer-based curcumin solid dispersion (SD), three acrylic polymers were used to formulate curcumin SD by solvent evaporation method. Curcumin Eudragit EPO SD (cur@EPO), curcumin Eudragit RS PO SD (cur@RSPO) and curcumin Eudragit RL PO SD (cur@RLPO) showed deep red, golden orange and reddish orange color, respectively. Cur@RSPO entrapped 15.42 wt% of curcumin followed by cur@RL PO and cur@EPO. FTIR spectra indicated that in cur@EPO, curcumin may transfer hydrogen to the dimethylaminoethyl methacrylate group and thus change its color to red. In contrast, curcumin may form hydrogen bonding with Eudragit RS PO and Eudragit RL. Curcumin exists in amorphous state in three SDs as proved by differential scanning calorimetry and X-Ray diffraction measurement. In vitro digestion presented that lower pH value in simulated gastric ﬂuid (SGF) stimulates the curcumin release from cur@EPO while permeability inﬂuences the release profile in other two SDs. When in simulated intestinal ﬂuid (SIF), first order release model governs the release behaviors of all three SDs which showed sustained release pattern. Our results are helpful to elucidate how structure of polymer may impact on the major properties of curcumin contained SD and will be promising to broaden its therapeutic applications.

Highlights

Curcumin [(1E, 6E)-1, 7-bis (4-hydroxy-3-methoxyphenyl)-1, 6-heptadiene-3, 5-ione] is the primary active compound of the perennial herb Curcuma Longa L. which has been used as nutritional supplement and herbal medicine in many Asian countries for thousands of years (Kharat, Zhang, McClements, 2018)
It is notable to point out that curcumin Eudragit E PO solid dispersion (SD) has deep red color while other two SDs show curcumin characteristic yellow color (Figure S1)
The halo X-Ray diffraction (XRD) pattern of curcumin SDs implies that no crystal compound exist, reinforces the observation of Differential scanning calorimetry (DSC) that in the all three acrylic polymer based SDs, curcumin exists in amorphous state rather than crystal state

Summary

INTRODUCTION

Curcumin [(1E, 6E)-1, 7-bis (4-hydroxy-3-methoxyphenyl)-1, 6-heptadiene-3, 5-ione] is the primary active compound of the perennial herb Curcuma Longa L. (turmeric) which has been used as nutritional supplement and herbal medicine in many Asian countries for thousands of years (Kharat, Zhang, McClements, 2018). SD is relatively easy to prepare, with higher loading ability and stability It is scalable and economic which makes this method particular appealing in the pharmaceutical industry. We prepared curcumin SD using the solvent evaporation method along with three model acrylic polymers: Eudragit E PO, Eudragit RS PO and Eudragit RL PO. Eudragit E PO is a polyelectrolyte that belongs to the family of (meth) acrylate copolymers It is composed of dimethylaminoethyl methacrylate, butyl methacrylate, and methyl methacrylate with the molar ratio of 2:1:1 (Gallardo, Skalsky, Kleinebudde, 2008). The results of this study can provide an insight into acrylic polymer based SD formulation which is helpful to promote the broad therapeutic activities of curcumin

MATERIAL AND METHODS

Preparation procedure

RESULTS AND DISCUSSION

CONCLUSIONS