Andrographolide (AG), a natural product with various pharmacological effects, exhibited low oral bioavailability owing to its poor solubility, stability, and low absorption. Previous studies have suggested that phospholipid (PC) and hydroxypropyl-β-cyclodextrin (HPCD) could improve the drug solubility and absorption. Moreover, nanoemulsion (NE) has been confirmed as an appropriate enhancer for oral bioavailability. Therefore, AG/HPCD/PC complex (AHPC) was synthesized, and AHPC-loaded nanoemulsion (AHPC-NE) was optimized and prepared using central composite design combined response surface methodology. The average droplet size and polydispersity index (PDI) were 116.50 5.99 and 0.29 0.03 nm, respectively. AHPC-NE with a loading capacity of 0.32 0.01% and an encapsulation efficiency of 96.43 2.27% appeared round and uniformly dispersed based on transmission electron microscopy. In vivo release studies demonstrated that AHPC-NE had good sustained-release effects. Further, AHPC-NE significantly enhanced the absorption of AG with a relative bioavailability of 550.71% compared to AG suspension. Such findings reveal AHPC-NE as a potential strategy for sustained-release and oral bioavailability enhancement.
Background and Purpose
Infections caused by
Staphylococcus aureus
(
S. aureus
) colonization in medical implants are resistant to antibiotics due to the formation of bacterial biofilm internal. Baicalein (BA) has been confirmed as an inhibitor of bacterial biofilm with less pronounced effects owing to its poor solubility and absorption. Studies have found that β-cyclodextrin-grafted chitosan (CD-CS) can improve drug efficiency as a drug carrier. Therefore, this research aims to prepare BA-loaded CD-CS nanoparticles (CD-CS-BA-NPs) for
S. aureus
biofilm elimination enhancement.
Methods
CD-CS-BA-NPs were prepared via the ultrasonic method. The NPs were characterized using the X-ray diffraction (XRD), Thermo gravimetric analyzer (TGA), Transmission electron microscopy (TEM) and Malvern Instrument. The minimum inhibitory concentration (MIC) of the NPs were investigated. The biofilm models in vivo and in vitro were constructed to assess the
S. aureus
biofilm elimination ability of the NPs. The Confocal laser method (CLSM) and the Live/Dead kit were employed to explore the mechanism of the NPs in promoting biofilm elimination.
Results
CD-CS-BA-NPs have an average particle size of 424.5 ± 5.16 nm, a PDI of 0.2 ± 0.02, and a Zeta potential of 46.13 ± 1.62 mV. TEM images revealed that the NPs were spherical with uniform distribution. XRD and TGA analysis verified the formation and the thermal stability of the NPs. The NPs with a MIC of 12.5 ug/mL exhibited a better elimination effect on
S. aureus
biofilm both in vivo and in vitro. The mechanism study demonstrated that the NPs may permeate into the biofilm more easily, thereby improving the biofilm elimination effect of BA.
Conclusion
CD-CS-BA-NPs were successfully prepared with enhanced elimination of
S. aureus
biofilm, which may serve as a reference for future development of anti-biofilm agents.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.