Preparation and in vitro evaluation of total alkaloids of Strychni Semen-total glucosides of paeony lipid-based cubic liquid crystalline nanoparticles / 中草药

Objective: To prepare total alkaloids of Strychni Semen (TASS) - total glucosides of paeony (TGP) lipid-based cubic liquid crystalline nanoparticles (TASS-TGP LLCN) and investigate its percutaneous absorption behavior. Methods: TASS-TGP LLCN was prepared by precursor injection method, and the encapsulation efficiency (EE) was determined by ultrafiltration centrifugation. The prescription of TASS-TGP LLCN was optimized by uniform design with the encapsulation efficiency as the index, and the basic properties of the optimized TASS-TGP LLCN were evaluated. Meanwhile, Poloxamer 407 (F127) was used as matrix to prepare gel, Franz diffusion method was used to compare the in vitro percutaneous permeability of TASS-TGP LLCN gel with TASS-TGP ordinary gel. Results: The optimal formula of TASS-TGP LLCN was glycerol monooleate (GMO) 1.0 g, F127 0.25 g, dispersed phase 60 mL. The EE of brucine, strychnine and paeoniflorin were all more than 50%, the average particle size was about (245.3 ± 16.4) nm, the pH value was 6.62, and the cubic structure was uniform in size under transmission electron microscope. The cumulate osmotic quantities in 24 h, the permeation rate and the skin retention volume of TASS-TGP LLCN gel were all better than ordinary gel of TASS-TGP. Conclusion: TASS-TGP LLCN has dual effects of promoting permeability and skin reservoir, which has a potential development prospect.

Formulation optimization of rutaecarpine lipid liquid crystalline nanoparticles by Box-Behnken design-response surface methodology / 中草药

Objective To optimize the formulation of rutaecarpine lipid liquid crystalline nanoparticles (Rut-LLCN) by Box-Behnken design-response surface methodology. Methods Rut-LLCN were prepared by precursor injection-high pressure homogenization method. A three factor and three-level Box-Behnken design was employed with the glyceryl monoolein quality, percentage of poloxamer in glyceryl monoolein and the rutaecarpine quality as independent variables, the entrapment efficiency, drug loading, mean particle size and polydispersity index as the dependent variables to sereen the optimal formaula. Results Optimized prescription was GMO 450 mg, F127-GMO 12%, and Rut 20 mg. All items of optimized prescription were similar to target values. According to the optimized prescription, the entrapment efficiency, drug loading, average particle size, and PDI of Rut-LLCN were (84.02 ± 7.99)%, (3.24 ± 0.30)%, (186.90 ± 13.50) nm, and 0.313 ± 0.020, respectively. Conclusion The prescription optimization model of Rut-LLCN was optimized by Box-Behnken designs-response surface methodology, and entrapment efficiency, drug loading, mean particle size, and PDI of Rut-LLCN are measured to investigate the model.

Analysis on intestinal absorption of paeoniflorin lipid liquid crystalline nanoparticles via everted intestinal sacs / 中国中药杂志

To study the absorption kinetics of paeoniflorin lipid liquid crystalline nanoparticles (Pae-LLCN) in different intestinal segments of rats and compare them with paeoniflorin(Pae) solution. Rat everted gut sac models were adopted for intestinal absorption test, and Pae content was determined by HPLC method to study the absorption characteristics of Pae-LLCN in rat duodenum, jejunum, ileum and colon, and investigate the effects of different drug concentrations on intestinal absorption. Results showed that Pae-LLCN and Pae were well absorbed at different intestine segments and different concentrations. The absorption constant Ka was increased with the increasing of the drug concentration, indicating possible passive absorption. The accumulative absorption volume Q and absorption constant Ka of Pae-LLCN were higher than those of Pae at each intestinal segment(P<0.05). The results revealed that Pae-LLCN and Pae could be well absorbed in whole intestinal segments and its mechanism may be passive absorption. LLCN can effectively improve the intestinal absorption of Pae.

Formulation and characterization of Liquid Crystalline Hydrogel of Agomelatin: In vitro and Ex vivo evaluation.

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.

Preparation of paeoniflorin lipid liquid crystalline nanoparticles and its in vitro release / 中草药

Objective: To prepare paeoniflorin lipid liquid crystalline nanoparticles (Pae-LLCN), and to study its in vitro release behavior. Methods: Using encapsulation efficiency (EE) as index, the Pae-LLCN were prepared by spontaneous emulsification and ultrasonic method, and the prescription of Pae-LLCN was optimized by orthogonal design. The in vitro release of Pae-LLCN within 24 h was measured by dialysis method, afterwards its morphology and particle size were studied by transmission electron microscope (TEM). Results: The optimal formulation was poloxamer-glycerol monooleate (1∶10), paeoniflorin inventory (40 mg), and PBS solution (20 mL). The average EE was 73.72%, the average DL was 14.81%, the size of nanoparticles was (170 ± 16) nm, and the 24 h in vitro accumulative release rate was 72.68%. Conclusion: The optimized process is rational and feasible, and the Pae-LLCN has good stability with better sustained release in vitro.