Dexamethasone loaded multi-layer poly-l-lactic acid/pluronic P123 composite electrospun nanofiber scaffolds for bone tissue engineering and drug delivery

Abstract

In tissue engineering, it is common to mix drugs that can control proliferation and differentiation of cells into polymeric solutions as part of composite to get bioactive scaffolds. However, direct incorporation of drugs might potentially result in undesired burst release. To overcome this problem, here we developed electrospun multilayer drug loaded poly-l-lactic acid/pluronic P123 (PLLA-P123) composite scaffolds. The drug was loaded into the middle layer. The surface, the mechanical and physiochemical properties of the scaffolds were evaluated. The drug release profiles were monitored. Finally, the osteogenic proliferation and differentiation potential were determined. The scaffolds fabricated here have appropriate surface properties, but with different mechanical strength and osteogenic proliferation and differentiation. Multi-layer scaffolds where the drug was in the middle layer and PLLA-plasma and PLLA-P123 with cover layer showed the best osteogenic proliferation and differentiation than the other groups of scaffolds. The drug release profiles of the scaffolds were completely different: single layer scaffolds showed burst release within the first day, while multilayer scaffolds showed controlled release. Therefore, the multilayer drug loaded scaffolds prepared have dual benefits can provide both better osteogenesis and controlled release of drugs and bioactive molecules at the implant site.

Dual-Crystallizable Silk Fibroin/Poly(L-lactic Acid) Biocomposite Films: Effect of Polymer Phases on Protein Structures in Protein-Polymer Blends

“…During the fabrication process, PLLA solutions were stirred under a magnetic field at a certain temperature [36][37][38][39]. Therefore, the magnetic force and temperature should play important roles in controlling the microstructure of the blended samples.…”

“…Figure 4 shows the XRD spectrum of pure SF (SP-0/5); pure PLLA (SP-5/0); and their composite films (SP-1/5, SP-3/5, SP-5/5, SP-5/3, and SP-5/1). The pure PLLA sample (SP-0/5) has two sharp peaks overlayed on a broad and amorphous dispersion peak with the diffraction peak at ~16.7° (200/100) stronger than that at ~18.9° (203); both peaks are the characteristic peaks of the α-crystal form of PLA [34][35][36]. The inserted graph in Figure 4b shows the enlarged XRD spectra of the pure SF sample (SP-5/0) in the 10°~45° region.…”

Surface mineralized hybrid nanofibrous scaffolds based on poly(l‐lactide) and alginate enhances osteogenic differentiation of stem cells

“…MSCs isolated from adipose tissue according to a procedure described previously, were used for cell assays. Briefly, 10 different donors were chosen (age 24–45) with full agreement.…”

Cancer Nanomedicine: A New Era of Successful Targeted Therapy

“…The accumulation of doxorubicin in tumors was more than free doxorubicin with normal distribution of polymer in normal tissues [85,86]. The mechanism of action of micelles is changing the structure of the membrane, decreasing membrane fluidization, and inhibiting function and expression of efflux transporters, such as P-gp and MRPs [87][88][89][90]. These subsequently sensitize resistant cancer cell to the chemotherapeutic agents [91], increasing the proapoptotic [92], decreasing the levels of glutathione (GSH) and glutathione-S-transferase (GST) activity, inhibiting the mitochondrial respiratory chain [92], decreasing oxygen consumption [93], and decreasing both mitochondrial membrane potentials [94], and the production of reactive oxygen species and release of cytochrome C in MDR cells are additional mechanisms [95,96].…”