The Release of Grape Pomace Phenolics from Alginate-Based Microbeads during Simulated Digestion In Vitro: The Influence of Coatings and Drying Method

Grape pomace is a byproduct of wineries and a sustainable source of bioactive phenolic compounds. Encapsulation of phenolics with a well-chosen coating may be a promising means of delivering them to the intestine, where they can then be absorbed and exert their health-promoting properties, including antioxidant, anti-inflammatory, anticancer, cardioprotective, and antimicrobial effects. Ionic gelation of grape pomace extract with natural coatings (sodium alginate and its combination with maltodextrins, gelatin, chitosan, gums Tragacanth and Arabic) was performed, and the resulting hydrogel microbeads were then air-, vacuum-, and freeze-dried to prevent spoilage. Freeze-drying showed advantages in preserving the geometrical parameters and morphology of the microbeads compared to other drying techniques. A good relationship was found between the physicochemical properties of the dried microbeads and the in vitro release of phenolics. Freeze-dried microbeads showed the highest cumulative release of phenols in the intestinal phase (23.65-43.27 mgGAE/gMB), while the most suitable release dynamics in vitro were observed for alginate-based microbeads in combination with gelatin, gum Arabic, and 1.5% (w/v) chitosan. The results highlight the importance of developing encapsulated formulations containing a natural source of bioactive compounds that can be used in various functional foods and pharmaceutical products.

[Preparation of microemulsion gel loading enriched ingredients of Epimedii Folium and its pharmacodynamics evaluation]

On the basis of previous studies, this study prepared and evaluated microemulsion gel loading enriched ingredients of Epimedii Folium and investigated its protective effect against peripheral nervous system damage caused by chemotherapeutics. The preparation method and the type and dosage of the matrix were investigated from rheology, preparation difficulty, and drug loading. Then the optimal prescription was determined and the microemulsion gel loading enriched ingredients of Epimedii Folium was prepared. The in vitro release and transdermal behaviors of the gel were investigated in the Franz diffusion cell with epimedin A1,A,B,C, and icariin as evaluation indicators. The oxaliplatin-induced peripheral neuropathy(OIPN) model was established in Wistar rats. The protective effect of the microemulsion gel loading enriched ingredients of Epimedii Folium against peripheral nervous system damage caused by chemotherapeutics was evaluated by behavioral measurement after drug administration and histopathological examination of dorsal root ganglia and sciatic nerve. The preparation process of the microemulsion gel loading enriched ingredients of Epimedii Folium was stable, and the release of the five components was consistent with the Hixson-Crowell cube root law. Behavioral indicators intuitively showed that the drug could effectively relieve mechanical allodynia caused by oxaliplatin. The histopathological examination showed that the drug can improve neuron damage in the dorsal root ganglia, axon degeneration, and demyelination caused by oxaliplatin. Therefore, the preparation process of the microemulsion gel loading enriched ingredients of Epimedii Folium is feasible, which can achieve stable drug release. It has a certain therapeutic effect on chemotherapy-induced peripheral neuropathy(CIPN).

Physicochemical Characterization and Pharmacokinetics of Agomelatine-Loaded PLGA Microspheres for Intramuscular Injection

PURPOSE

The aim of this study was to design agomelatine loaded long acting injectable microspheres, with an eventual goal of reducing the frequency of administration and improving patient compliance in treatment of depression.

METHODS

AGM-loaded microspheres were prepared by an O/W emulsion solvent evaporation method. The physicochemical properties and in vitro performance of the microspheres were characterized. The pharmacokinetics of different formulations with various particle sizes and drug loadings were evaluated.

RESULTS

AGM-loaded microspheres with drug loading of 23.7% and particle size of 60.2 μm were obtained. The in vitro release profiles showed a small initial burst release (7.36%) followed by a fast release, a period of lag time and a second accelerated release. Pore formation and pore closure were observed in vitro, indicating that the release of drug from microspheres is dominated by water-filled pores. Pharmacokinetic studies showed that AGM microspheres could release up to 30 days in vivo at a steady plasma concentration. As well, particle size and drug loading could significantly influence the in vivo release of AGM microspheres.

CONCLUSIONS

AGM-loaded microspheres are a promising carrier for the treatment of major depressant disorder.

In-vitro and in-vivo evaluation of ciprofloxacin liposomes for pulmonary administration

OBJECTIVE

The aim of this study was to investigate the ciprofloxacin liposome of high encapsulation efficiency with optimal physical properties for pulmonary administration and to test its in-vivo potential in rats.

METHODS

Ciprofloxacin-loaded liposome was prepared by gradient of ammonium sulfate method. The particle size and morphology were determined using a NANOPHOX particle size analyzer and a transmission electron microscope, respectively. Encapsulation efficiency was calculated by UV spectrophotometry. Ciprofloxacin liposome released in vitro was performed using simulated lung fluid. In-vivo studies, pharmacokinetics and pulmonary distribution, HPLC method was established to determine the concentration of ciprofloxacin in rat plasma and lung tissue. The pulmonary pathological section was used to observe the change of pulmonary pathology.

RESULTS

The optimized ciprofloxacin liposome, which had a high encapsulation efficiency of 93.96%, and an average particle size of 349.6 nm with a span of 0.42, showed sustained in-vitro release. The optimized ciprofloxacin liposome was further examined in the in-vivo study in rats. The concentration of ciprofloxacin in lung and blood was simultaneously determined in each rat. The ratio of the AUClung value between ciprofloxacin liposome and ciprofloxacin solution was 288.33, whereas the relative bioavailability was 72.42%, and the drug targeting efficiency of ciprofloxacin liposome and ciprofloxacin solution by intratracheal administration were 799.71 and 2.01, respectively.

CONCLUSION

Ciprofloxacin liposome for pulmonary administration offered an attractive alternative that was able to deliver high concentrations of antibiotic directly to the chosen target site while minimizing the local irritation.