ABSTRACT
Due to the high similarity with the lipid layer between human skin keratinocytes, functional cosmetics with layered liquid crystal structure prepared by liquid crystal emulsification technology encapsulating natural active substances have become a hot research topic in recent years. This type of functional cosmetic often has a fresh and natural skin feel, excellent skin barrier repair function and efficient moisturizing effect, etc., showing great potential in cosmetic application. However, the present research on the application of liquid crystal emulsification technology to functional cosmetics is still in the initial stage, and there are fewer relevant reports with reference values. Based on the mentioned above, this review provides a comprehensive summary of functional cosmetics with layered liquid crystal structures prepared by liquid crystal emulsification technology from the following aspects: the structure of human skin, the composition of lamellar liquid crystal, the advantages of liquid crystal emulsification technology containing natural active substances used in the field of functional cosmetics, the preparation process, main components, influencing factors during the preparation and the market functional cosmetics with lamellar liquid crystal structure. Finally, the prospect of the application of liquid crystal emulsification technology in functional cosmetics is presented, to provide useful references for those engaged in the research of liquid crystal emulsification technology-related functional cosmetics.
ABSTRACT
Objective To prepare TOGA-X4 microparticles with uniform size and good rehydration property and to obtain the stable and reliable preparation process, and evaluate the in vitro release characteristics. Methods With the average particle size, polydispersity index and rehydration as indexes, optimizing the process of antitumor active substance TOGA-X4 microparticles by stainless steel rapid film emulsification method through single factor investigation to investigate the factors influencing the size and dispersion of the drug microparticles and observe the morphology of the particles by scanning electron microscopy. With the cumulative release degree of TOGA-X4 as index, direct drug release method was adopted to determine the cumulative release rate of TOGA-X4 and the size of TOGA-X4 microparticles. The curve of in vitro drug release was fitted with different release model to estimate the in vitro release characteristics of TOGA-X4 raw powders and TOGA-X4 microparticles. Results The optimized preparation technology contained TOGA-X4 mass concentration of 5 mg/mL in oil phase, PVA mass concentration of 30 mg/mL in for aqueous phase, the ratio of oil to water was 1:1, transmembrane pressure at 0.4 MPa, sucrose aqueous solution of 50 mg/mL as freeze-drying protective agent, curing temperature at 70 ℃; Compared with other in vitro release models, the logistic equation was the fittest model to TOGA-X4 microparticles, zero order equation was the fittest model to TOGA-X4. Conclusion The preparation of microparticles by stainless steel rapid film emulsification is simple, stable and reliable, which can improve the dissolution rate of insoluble drugs and has advantages in the preparation of microparticles of poorly water-soluble drugs.
ABSTRACT
Objective: The aim of this investigation was the development and characterization of Agomelatin-loaded liquid crystalline (AM-LC) nanoparticles for improved topical application. Methods: AM-LC was formulated with the glyceryl monooleate (GMO) and poloxamer 407 as structure forming agent (lipid) and surfactant respectively, by using emulsification of GMO and poloxamer in water using a hydrotrope (Cubosomes) formation method. The obtained dispersion was characterized for particle size, PDI, zeta potential, entrapment efficiency, surface morphology, in vitro studies. Further, conversion optimised formulation in to cubic gel by incorporating 0.5% w/w of carbopol 934P. The prepared gel was characterized by rheological measurements, surface pH and ex vivo permeation studies through the rat skin. Results: The average particle size of formulations was ranging from 187.6±3.97nm to 225.8±7.54nm and ZP from -14.5±4.65 to -23.5±3.86mV. In vitro drug release from cubosomes exhibited sustained release profile and the optimized formulation (F2) showed cumulative drug release of 83.96±2.43% during 24h. Transmission electron microscopic photographs confirmed that the formed liquid crystalline nanoparticles were cubic in shape. Results suggested that cubic gel exhibited a retarded release rate (53.5 ± 3.21%) than the control gel (95.33 ± 2.28%) containing 0.1% drug solution. Conclusion: The obtained results indicated that cubic gel would be a promising carrier for topical delivery of agomelatin into and across the skin.
ABSTRACT
The purpose of the present study was to prepare, characterize and evaluate the colon-targeted microspheres of mesalamine for the treatment and management of ulcerative colitis (UC). Microspheres were prepared by the ionic-gelation emulsification method using tripolyphosphate (TPP) as cross linking agent. The microspheres were coated with Eudragit S-100 by the solvent evaporation technique to prevent drug release in the stomach. The prepared microspheres were evaluated for surface morphology, entrapment efficiency, drug loading, micromeritic properties and in-vitro drug release. The microspheres formed had rough surface as observed in scanning electron microscopy. The entrapment efficiency of microspheres ranged from 43.72%-82.27%, drug loading from 20.28%-33.26%. The size of the prepared microspheres ranged between 61.22-90.41μm which was found to increase with increase in polymer concentration. All values are statistically significant as p<0.05. Micromeritic properties showed good flow properties and packability of prepared microspheres. The drug release of mesalamine from microspheres was found to decrease as the polymer concentration increases. The release profile of mesalamine from eudragit-coated chitosan micro-spheres was found to be pH dependent. It was observed that Eudragit S100 coated chitosan microspheres gave no release in the simulated gastric fluid, negligible release in the simulated intestinal fluid and maximum release in the colonic environment. It was concluded from the study that Eudragit-coated chitosan microspheres were promising carriers for colon-targeted delivery of Mesalamine.
ABSTRACT
The purpose of the present study was to prepare, characterize and evaluate the colon-targeted microspheres of mesalamine for the treatment and management of ulcerative colitis (UC). Microspheres were prepared by the ionic-gelation emulsification method using tripolyphosphate (TPP) as cross linking agent. The microspheres were coated with Eudragit S-100 by the solvent evaporation technique to prevent drug release in the stomach. The prepared microspheres were evaluated for surface morphology, entrapment efficiency, drug loading, micromeritic properties and in-vitro drug release. The microspheres formed had rough surface as observed in scanning electron microscopy. The entrapment efficiency of microspheres ranged from 43.72%-82.27%, drug loading from 20.28%-33.26%. The size of the prepared microspheres ranged between 61.22-90.41μm which was found to increase with increase in polymer concentration. All values are statistically significant as p<0.05. Micromeritic properties showed good flow properties and packability of prepared microspheres. The drug release of mesalamine from microspheres was found to decrease as the polymer concentration increases. The release profile of mesalamine from eudragit-coated chitosan micro-spheres was found to be pH dependent. It was observed that Eudragit S100 coated chitosan microspheres gave no release in the simulated gastric fluid, negligible release in the simulated intestinal fluid and maximum release in the colonic environment. It was concluded from the study that Eudragit-coated chitosan microspheres were promising carriers for colon-targeted delivery of Mesalamine.