Release behaviors and kinetics of coated bead-on-string nanofibrous multilayer membranes loaded with drug particles

A bead-on-string structure with special beads at the microscale level could act as an effective carrier for solid drug particles as well as giving a continuous and sustained release profile. Tetracycline hydrochloride (TCH), used as solid model drug particles, was ground to obtain nanoscale and well-distributed size. Electrospun poly[lactic- co -(glycolic acid)] (PLGA) bead-on-string nanofibers loaded with TCH of different particle sizes were fabricated for controlled drug delivery. The morphology of TCH particles and bead-on-string nanofibers were observed using a particle sizer and scanning electron microscopy. The effects of drug particle size on the release behaviors of nanofibers were further investigated and analyzed using UV–visible spectrophotometry. In vitro release results suggested that bead-on-string nanofibers encapsulating ground TCH particles had higher total drug release quantity compared with unground particle-loaded nanofibers. Coating of the surface of PLGA/TCH nanofibers was investigated for controlled-release effects and the release mechanism to understand the drug–polymer carrier interaction. The results indicated that coating on both sides of nanofibrous membranes could effectively decrease the initial burst release. Bead-on-string nanofibers proved to be promising mats for drug delivery applications. © 2021 Society of Industrial Chemistry.