Microcapsules based on alginate and guar gum for co-delivery of hydrophobic antitumor bioactives.

The main goal was the development of a polysaccharide microcapsule for anticancer application based on guar gum and sodium alginate for the controlled release of hesperidin and betulinic acid by spray drying technique. The microcapsule showed an Encapsulation Efficiency of 98.15 ± 0.34 % for hesperidin and 99.76 ± 0.22 % for betulinic acid. In the release study, the Korsmeyer-Peppas mathematical model was identified as the most adequate to explain the observed release mechanism. In vivo tests were performed in zebrafish model, revealing that the microcapsules did not alter the locomotor activity and were not toxic within 96 h by oral administration, suggesting their biological safety. In vitro cytotoxic activity against HL-60 cells confirmed an IC50 value of 2.52 ± 0.23 µg mL-1 in 72 h. Additionally, a decrease in the cytotoxic activity of betulinic acid against L-929 (non-tumor) cells was evidenced. Therefore, the microcapsules synthesized in this work represent a promising formulation for anticancer applications.

Starch-based magnetic nanocomposite for targeted delivery of hydrophilic bioactives as anticancer strategy.

Magnetic nanocomposites were synthesized for the targeted delivery of hydrophilic bioactives through guidance generated by a magnetic field. Superparamagnetic iron oxide nanoparticles (SPIONs) were used to generate hydroxyethyl starch magnetic nanocapsules (HES MNCs). This synthesis allowed the co-encapsulation of oncocalyxone A (onco A) and surface-modified magnetite nanoparticles (Fe3O4@citrate) into the same nanostructure. The synthesized nanocapsules exhibited a core-shell morphology, with an average diameter of 143 nm. This nanocomposite showed potential anticancer activity (IC50) against four human tumor cell lines: glioblastoma SNB-19 (1.010 µgmL-1), colon carcinoma HCT-116 (2.675 µgmL-1), prostate PC3 (4.868 µgmL-1), and leukemia HL-60 (2.166 µgmL-1). Additionally, in vivo toxicity and locomotor activity were evaluated in a zebrafish (Danio rerio) model. The nanocomposite exhibited in vitro cytotoxicity, prolonged drug release profile and also responded to an applied magnetic field, representing a versatile compound with perspectives for highest concentration of different hydrophilic bioactives in a target tissue through magnetic vectorization.

Antibacterial activity of fluoxetine-loaded starch nanocapsules.

This work proposes the development of a starch-based drug carrier for fluoxetine (FLX) delivery and evaluate the improvement of the drug antibacterial activity. The starch nanocapsules were prepared via interfacial polyaddition reaction presenting a core-shell morphology, based on polyurethane linkage, with a particle size in the range 250-300 nm. Furthermore, FLX-loaded nanocapsules were evaluated regarding antibacterial potential against Staphylococcus aureus (ATCC® 6538P ™) and its clinical strains of methicillin-resistant. As expected, the FLX-loaded presented lower minimum inhibitory concentration (MIC) values, in the range of 190-95 µg mL-1, against all isolated microorganisms in comparison to FLX, 255 µg mL-1. According to results, the FLX-loaded starch nanocapsules have successfully improved drug antibacterial activity, generating promising perspectives on the field of the hydrophilic drug delivery systems.