ABSTRACT
Objective To prepare lutein ester (LE) nanoparticles (LE-NPs) by anti-solvent method using tetrahydrofuran as solvent, deionized water as antisolvent and Poloxamer 188 as surfactant, and to optimize the process of getting LE-NPs. Methods The concentration of LE, ratio of solvent to solvent, type and dosage of surfactant, precipitation time and stirring speed were investigated factors affecting the particle size of LE-NPs. The raw LE and LE-NPs were observed and analyzed by scanning electron microscopy, laser particle size analyzer, X-ray diffraction, and differential scanning calorimetry; Solvent residue was tested by GC method. What’s more, the solubility and dissolving capability of raw LE and LE-NPs also were detected in vitro in this study. Results The optimized preparation conditions of LE-NPs were as follows: 10 min of stirring time, 50 mg/mL of LE concentration, 1∶7 of the volume ratio of solvent to antisolvent, 0.5% at mass fraction of poloxamer 188, 950 r/min of stirring speed, 25 ℃ of precipitation temperature. The mean particle size of spherical LE-NPs was 164 nm. XRD and DSC results showed that LE-NPs had lower crystallinity compared to raw drug, and mainly in amorphous state. The solvent residue result showed that tetrahydrofuran residue content in LE-NPs was 344.3 μg/g. Furthermore, the solubility and dissolution rate of LE-NPs were about 2.91 times and 9.65 times of raw LE. Conclusion LE-NPs prepared by antisolvent method could become a new formulation, which has higher solubility and bioavailability than raw LE.
ABSTRACT
Objective: Curcumin nanoparticles lyophilized powder (CNLP) were prepared by antisolvent method which was optimized using single factor method. In this process, acetone was used as solvent, deionized water was used as antisolvent, tween-80 was used as surfactant and mannitol was used as lyoprotectant. Methods: The main factors affecting the particle size of CNLP included the concentration of curcumin, volume ratio of solvent and antisolvent, dosage of surfactant, precipitation time, stirring speed, and dosage of lyoprotectant. The contrast experiments on dissolution in vitro was done between CNLP and raw curcumin powder. Results: The mean particle size of CNLP was (172.2 ± 4.6) nm; The Zeta potential of CNLP redissolving in water was (-19.7 ± 3.7) mV. The SEM graphs indicated the raw curcumin was in irregular and massive shape and its particle size was about 20 μm. The CNLP exhibited regular block structure and its particle size was about 170 nm which was obviously reduced compared with raw curcumin. The mean particle size of CNLP obtained from laser particle analyzer was in accord with the morphology of CNLP. The saturated solubility of CNLP was 41.32 times of raw curcumin powder in deionized water, 1.74 times in simulated gastric fluid and 4.11 times in simulated intestinal fluid through saturated solubility test, respectively. The dissolution rate of CNLP was 14.51 times of raw curcumin powder in water dissolution medium, 2.33 times in simulated gastric fluid and 44.79 times in simulated intestinal fluid through dissolution determination, respectively. Conclusion: The preparation process of CNLP using antisolvent method could improve the drawback of poor water solubility and enhance the bioavailability of curcumin.