Psoralen (PSO) and 5-methoxypsoralen (5-MOP) are widely used drugs in oral photochemotherapy against vitiligo and major bioactive components of root bark extract of Brosimum gaudichaudii Trécul (EBGT), previously standardized by LC-MS. However, the exceptionally low water solubility of these psoralens can cause incomplete and variable bioavailability limiting their applications and patient adherence to treatment. Therefore, the purpose of this work was to investigate the effects of 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex on the solubility and jejunal permeability of PSO and 5-MOP from EBGT. Characterization of inclusion complexes were evaluated by current methods in nuclear magnetic resonance studies on aqueous solution, Fourier transform infrared spectroscopy, thermal analysis, and scanning electron microscopy in solid state. Ex vivo rat jejunal permeability was also investigated and compared for both pure psoralens and plant extract formulation over a wide HP-β-CD concentration range (2.5 to 70 mM). Phase solubility studies of the PSO- and 5-MOP-HP-β-CD inclusion complex showed 1:1 inclusion complex formation with small stability constants (K_c < 500 M⁻¹). PSO and 5-MOP permeability rate decreased after adding HP-β-CD by 6- and 4-fold for pure standards and EBGT markers, respectively. Nevertheless, the complexation with HP-β-CD significantly improved solubility of PSO (until 10-fold) and 5-MOP (until 31-fold). As a result, the permeability drop could be overcome by solubility augmentation, implying that the HP-β-CD inclusion complexes with PSO, 5-MOP, or EBGT can be a valuable tool for designing and developing novel oral drug product formulation containing these psoralens for the treatment of vitiligo.

Hydrocotyle umbellata L., Araliaceae, is a species that is recommended in Ayurvedic medicine for its effects on the central nervous system, such as anxiolytic and memory-stimulant effects. Despite the medicinal potential of this species, its phytopharmaceutical and technological potential to produce standardized extracts has not been investigated. This study analyzes the influence of spray drying parameters on the contents of the chemical markers (total phenolic, total flavonoid, and hibalactone) and the functional properties of H. umbellata extract. The optimization of drying conditions was performed using a central composite design combined with response surface methodology and desirability function approach. The mathematical models fitted to experimental data indicated that all the evaluated drying parameters significantly influenced the chemical contents. The optimal conditions were: inlet temperature of 120 °C, feed flow rate of 4 mL min^-1, and colloidal silicon dioxide:maltodextrin ratio of 16%:4%. Under these conditions, the powder samples had spherical particles and desirable physicochemical and functional properties, such as low water activity and moisture content, good product recovery, reconstitution, and flowability. Thus, spray drying might be a promising technique for processing standardized H. umbellata extracts.

Background: Topotecan (TPT) is a water-soluble derivate of camptothecin, which undergoes ring-opening hydrolysis in neutral solutions, leading to stability loss and poor cellular uptake. Lipid nanoencapsulation can improve TPT stability, and polymer-lipid hybrid nanoparticles (PLN) are interesting alternatives to improve TPT nanoencapsulation. Objective: This study seeks to prepare complexes between the cationic TPT and the negatively charged dextran sulfate (DS) with a view of improving drug loading, chemical stability and release control. Methods: The optimum ionic molar ratio in DS-TPT complexation was determined, and the selected complex was characterized by FTIR and solid-sate 13C NMR. TPT solubility in the free and complexed forms was also assayed. TPT-PLN was then obtained via a microemulsion technique, and particle size, zeta potential, encapsulation efficiency, drug loading and drug recovery were determined. Additionally, the TPT stability and in vitro release were determined from PLN and compared with free TPT, TPT-DS complex and TPT encapsulated in nanostructured lipid carriers (NLC) of similar composition. Results: TPT-DS complexation was confirmed by FTIR and NMR. TPT solubility in the complex was drastically decreased when compared to free TPT. TPT-PLN had high encapsulation efficiency (97%) and drug loading capacity (5.5%). Additionally, TPT-PLN showed a mean diameter, polidispersivity index e zeta potential of 140 nm, 0.2 and -22 mV, respectively. The TPT chemical stability and release from PLN was superior when compared to NLC. Conclusion: PLN has shown to be a more effective nanosystem for TPT nanoencapsulation because TPT loading, stability and release were superior when compared to TPT-NLC.

Drug-excipient interaction studies are fundamental for the efficient development of new formulations. These interactions directly influence drug stability, loading capacity, controlled release, and bioavailability, which are essential aspects to optimize therapeutic efficacy and minimize possible adverse effects. This research aimed to investigate the physicochemical compatibility of OLZ with lipid excipients intended for NLC formulation. Binary mixtures (1:1, w/w) of OLZ with a range of solid, liquid lipids and surfactants were examined using thermogravimetry (TG/DTG) and differential thermal analysis (DTA), and Fourier-transform infrared spectroscopy (FTIR). Isothermal stress tests were conducted at 60 ± 2 °C for a period of up to 30 days, and the OLZ content was measured using a validated HPLC method. The thermal and spectral analyses indicated interactions between OLZ and excipients such as oleic acid, Capmul®, Captex®, and Span® 60, as demonstrated by shifts or suppression of characteristic OLZ peaks. The degradation observed under stress conditions confirmed limited stability with stearic acid, lauric acid, palmitic acid, glyceryl monostearate, oleic acid, Capmul® and Span®60 and 80 , with OLZ content reduced to 55.6–70.6% after 30 days in the most affected mixtures, compared to 100.0 ± 2.9% for pure OLZ. Overall, these findings emphasize the significance of excipient selection to guarantee stability and compatibility in the formulation of OLZ-loaded NLC systems.

The solidification of self-microemulsifying drug delivery systems (SMEDDS) represents a significant advance in the transition from self-microemulsifying te