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Different types of implants are used in orthopedic applications. Due to the stress shielding and a second surgery caused by applying metal implants as orthopedic joints, using biodegradable bone implants with antibacterial properties is advantageous. Therefore, this study aims at fabricating a multifunctional poly (lactic acid) (PLA)-polycaprolactone (PCL)-based scaffold reinforced with hydroxyapatite (HA) and zinc oxide (ZnO) nanoparticles. Solvent casting combined with die-casting techniques was employed for fabricating the scaffolds, and their physical, mechanical, and biological properties were characterized. The morphology of the samples and the growth of hydroxyapatite crystals on the surface of the samples were examined by field emission scanning electron microscope. In dry conditions, adding nanoparticles to the scaffolds has significantly (p <.05) increased the tensile Young's modulus from 450.00 ± 87.18 MPa to 1050.66 ± 104.05 MPa. Also, adding ZnO has improved the antibacterial properties of the scaffolds against S.aureus and E.coli bacteria strains. Moreover, the MTT assay results (after 72 h cell culture) show that the viability of L929 cells has increased from 22.18 ± 0.62% for the PLA-PCL scaffold to 70.03 ± 0.25% for the optimal nanostructure (p <.05). In conclusion, the PCL-PLA/HA/1% ZnO scaffold could potentially be used as absorbable spongy bone implants. [ABSTRACT FROM AUTHOR]

The development of sustainable drug delivery systems is very important in the field of pharmaceutical research and has many advantages over the usual methods of drug administration, including improving effectiveness, reducing side effects, and increasing patient compliance. Among various techniques, electrospraying as a voltage‐driven process has emerged as a promising technology for the fabrication of drug‐loaded nanoparticles. In recent years, the application of electrospray approach for drug release has been widely investigated. However, optimization of electrospray process parameters and development of mathematical models to predict drug release kinetics from microparticles are still challenging. To address these issues, a combination of Central Composite Design (CCD) and Response Surface Methodology (RSM) has been used. This paper focuses on the application of CCD‐RSM for modeling and optimization of doxorubicin (DOX)‐poly(caprolactone) (PCL)‐polyethylene glycol (PEG) microparticles prepared using electrospray method. Doxorubicin, a widely used anticancer drug, exhibits potent cytotoxicity against a wide range of cancers. PCL‐PEG microparticles are promising as drug carriers due to their biocompatibility, controlled release properties, and ability to protect the encapsulated drug from degradation. The CCD‐RSM approach allows systematic investigation and optimization of several formulation and process variables, including polymer concentration, PCL‐PEG weight ratio, and applied voltage on drug release behavior. In addition, the effect of rheology and electrical conductivity of polymer fluid on the size of particles obtained from electrospraying was investigated. The effect of adding folic acid and doxorubicin in the optimized sample of nanoparticles and the effect of different concentrations of doxorubicin were investigated, and SEM, DLS, and FTIR techniques were used to characterize the microparticles, and the MMT test was performed to evaluate their cytotoxicity. The results showed that the optimized formulation is effective for sustained drug release over a long period for drug delivery applications. [ABSTRACT FROM AUTHOR]

Nanocomposites containing clay nanoparticles often present favorable properties such as good mechanical and thermal properties. They frequently have been studied for tissue engineering (TE) and regenerative medicine applications. On the other hand, poly(glycerol sebacate) (PGS), a revolutionary bioelastomer, has exhibited substantial potential as a promising candidate for biomedical application. Here, we present a facile approach to synthesizing stiff, elastomeric nanocomposites from sodium‐montmorillonite nano‐clay (MMT) in the commercial name of Cloisite Na+ and poly(glycerol sebacate urethane) (PGSU). The strong physical interaction between the intercalated Cloisite Na+ platelets and PGSU chains resulted in desirable property combinations for TE application to follow. The addition of 5% MMT nano‐clay resulted in an over two‐fold increase in the tensile modulus, increased the onset thermal decomposition temperature of PGSU matrix by 18°C, and noticeably improved storage modulus of the prepared scaffolds, compared with pure PGSU. As well, Cloisite Na+ enhanced the hydrophilicity and water uptake ability of the samples and accelerated the in‐vitro biodegradation rate. Finally, in‐vitro cell viability assay using L929 mouse fibroblast cells indicated that incorporating Cloisite Na+ nanoparticles into the PGSU network could improve the cell attachment and proliferation, rendering the synthesized bioelastomers potentially suitable for TE and regenerative medicine applications. [ABSTRACT FROM AUTHOR]