ABSTRACT
Timolol maleate cubic nanoparticles (TM-LCNPs) were prepared via fragmentation of a bulk GMO/poloxamer 407 cubic phase gel by high-pressure homogenization. The optimal prescription was selected based on particle size and entrapment efficiency by orthogonal design method. Malvern particle sizer, polarized light microscopy, and differential scanning calorimetry were used to characterize the cubic nanoparticles. Commercial eye drops were used as a control for the release and corneal permeation experiment in vitro. Fluorescence imaging was used to observe the retention of Rhodamine B cubic nanoparticles (RhB-LCNPs) in rabbit cornea. The results indicated that the optimal prescription and preparation of TM-LCNPs was oil-water ratio (7:3), homogenous pressure (900 bar), the number of homogenizations (6) and drug loading (1%). Corneal permeability of TM-LCNPs was significantly higher than that of commercially available eye drops. The residence time in eyes was longer which suggested a sustained release behavior. The pathology result of rabbit corneal after multiple administration of TM-LCNPs showed that there was no apparent damage.
ABSTRACT
OBJECTIVE: To prepare oridonin-loaded cubosomes, and encapsulate oridonin(ORI) for the purpose of enhancing the solubility and prolonging the action time. METHODS: Phytantriol (PYT) was firstly used to cooperate with Poloxamer 407-propylene glycol-water system to improve the solubility of ORI for developing ORI-loaded cubosomes. Polarizing microscope, small angel X-ray scattering (SAXS) and cryogenic transmission electron microscopy(cryo-TEM) were used to study the characters of cubosomes. RESULTS: Under homogenization conditions of 1 200 bar for 9 cycles, the obtained PYT-based cubosomes had narrow particle size distribution with a mean particle size of (225.9 ± 5.6) nm. The internal structures of cubosomes were revealed by small-angle X-ray scattering as a bicontinuous cubic liquid crystalline phase with Pn3m geometry. The encapsulation efficiency and drug loading determined by ultrafiltration centrifugation were (86.6 ± 1.5)% and (3.69 ± 0.06) mg•g-1, the solubility of ORI had been increased by 5.20 times. CONCLUSION: The optimized formulas of cubosomes show obvious 24 h-sustained release, and the in vitro release profiles fitt the Higuchi release model well, implying diffusion-control as main release mechanism.
ABSTRACT
Liquid crystalline nanoparticles are composed of a certain concentration of amphiphilic lipid self-assembly in water. The attractiveness of this formulation is linked to the nanostructural versatility, compatiblity, digestiblity and bioadhesive properties of their lipid constituents, and the capability of solubilizing and sustaining the release of amphiphilic, hydrophobic and hydrophilic drugs. Liquid crystalline nanoparticles, as a novel drug delivery system, have great promise in drug delivery. The carrier materials, preparation methods, characterization and applications of liquid crystalline nanoparticles were reviewed based on relevant articles published in recent years to provide reference for further study of liquid crystal nanoparticles.
ABSTRACT
This review introduced the structural characteristics, drug carrier materials, preparation and exosyndrome of cubosomes. The authors mainly analyzed the advantages, prospect and existing problems of cubosomes as apotential drug delivery system for transdermal administration to provide a reference for further development of cubosomes as a drug delivery system for transdermal administration.