A novel core-shell rifampicin/isoniazid electrospun nanofiber membrane for long time drug dissolution

Rifampicin (RIF) and isoniazid (INH) are commonly applied jointly in clinical to improve the treatment efficacy of tuberculosis. Due to the metabolism of the kidneys, most of RIF and INH would be excreted by human bodies after reaching a high drug concentration, which causes serious waste of drugs and does harm to our health. In this study, polylactic acid (PLLA) was chosen as the carrier to prepare core-shell drug-loaded nanofibers with RIF in the shell and INH in the core by coaxial electrospinning. The results showed that the average diameter of the core-shell drug-loaded fibers with an obvious core-shell structure was about 650 nm. Parts of RIF and INH in the fibers became amorphous; the rest maintained crystalline. The combination of PLLA and RIF made the fibers obvious hydrophobic and exhibited a slowly phased sustained-dissolve property during in vitro dissolution studies. The in vitro antibacterial experiments confirmed that the core-shell drug-loaded nanofibers had a favorite inhibitory effect on Staphylococcus aureus, which endowed practical medical value to the fibers. The core-shell drug-loaded nanofibers effectively separated RIF and INH, preventing the degradation of RIF caused by the direct contact of the two drugs. The slow-dissolve characteristics can maintain a relatively stable drug concentration and avoid the damage to the human body caused by the quick dissolve and rapid metabolism of drugs. The combination with coaxial electrospinning fills the gap in the core-shell system with two drugs and has great significance in the future. © 2022