Background: Curcumin and Thymoquinone are very well-known phytochemicals for their potent anti-inflammatory and anticancer properties. The major challenges for curcumin is its poor aqueous solubility and erratic oral bioavailability.
Objective: To develop a novel liquid self-nanoemulsifying drug delivery system (SNEDDS) containing curcumin and thymoquinone and further converted into a solid dosage form using adsorbents Syloid® and Neusilin® as the solid carrier.
Methods: The characterization of the liquid and solid SNEDDS was performed by particle size & zeta potential analysis, scanning electron microscopy, differential scanning calorimetry, fourier transform infrared spectroscopy and X-ray powder diffraction. The drug loading, and in vitro release studies were carried out to investigate the efficiency of curcumin release from SNEDDS.
Results: The liquid SNEDDS containing black seed oil showed excellent self-emulsification performance with transparent appearance. The results of characterization studies showed that solidification using 50% (w/w) Syloid® and Neusilin® in the liquid formulation yield free flowing powder with no agglomeration but Neusilin® produced smooth granules than Syloid® and kept the drugs stable in amorphous state. In vitro dissolution studies indicated that liquid SNEDDS formulations of F4 and its solid SNEDDS using Neusilin® provided high dissolution efficiency and reproducibility for curcumin and thymoquinone. However, Neusilin® showed higher rate of dissolution (more than 65%, p < 0.05) compared to Syloid® for curcumin.
Conclusions: Curcumin loaded-SNEDDS formulation containing thymoquinone in liquid & solid dosage forms were successfully developed with an increased drug loading and dissolution rate, which could be the potential combined delivery system for various anti-inflammatory and anti-cancer treatments.
Keywords: Combined therapeutic effects; Curcumin; Self-nanoemulsifying drug delivery systems (SNEDDS); Solubility improvement; Thymoquinone.