The engineering, drug release, and in vitro evaluations of the PLLA/HPC/Calendula Officinalis electrospun nanofibers optimized by Response Surface Methodology.

A system based on poly(l-lactic acid) (PLLA) and hydroxypropyl cellulose (HPC) was considered in this study to achieve electrospun mats with outstanding properties and applicability in biomedical engineering. A novel binary solvent system of chloroform/N,N-dimethylformamide (CF/DMF:70/30) was utilized to minimize the probable phase separation between the polymeric components. Moreover, Response Surface Methodology (RSM) was employed to model/optimize the process. Finally, to scrutinize the ability of the complex in terms of drug delivery, Calendula Officinalis (Marigold) extract was added to the solution of the optimal sample (Opt.PH), and then the set was electrospun (PHM). As a result, the presence of Marigold led to higher values of fiber diameter (262 ± 34 nm), pore size (483 ± 102 nm), and surface porosity (81.0 ± 7.3 %). As this drug could also prohibit the micro-scale phase separation, the PHM touched superior tensile strength and Young modulus of 11.3 ± 1.1 and 91.2 ± 4.2 MPa, respectively. Additionally, the cumulative release data demonstrated non-Fickian diffusion with the Korsmeyer-Peppas exponent and diffusion coefficient of n = 0.69 and D = 2.073 × 10-14 cm2/s, respectively. At the end stage, both the Opt.PH and PHM mats manifested satisfactory results regarding the hydrophilicity and cell viability/proliferation assessments, reflecting their high potential to be used in regenerative medicine applications.

Interface modified polylactic acid/starch/poly ε-caprolactone antibacterial nanocomposite blends for medical applications.

In this study, an optimized interface-modified ternary blend with antibacterial activity based on polylactic acid/starch/poly ε-caprolactone (PLASCL20), mixed with nano hydroxyapatite (nHA) via melt blending. This method results in a homogeneous nanocomposite blend in which the addition of 3% nHA improves the overall properties such as hydrolytic degradation, hydrophilicity, antibacterial activity and the drug release comparing to PLASCL20. Moreover, the simultaneous use of nHA and encapsulated triclosan (LATC30) compensated the negative effect of triclosan through increasing the possible cell attachment. According to the contact angle results, nHA was thermodynamically driven into the interface of PLA and PCL/Starch phases. The addition of 3% nHA showed a good adjustment between the hydrolytic degradation and the release profile, therefore, their electrospun microfibers demonstrated an improved fibroblast (L929) cell attachment. The aforementioned nanocomposite blend is a suitable antibacterial candidate for many medical applications with minimum side effects due to the controlled release of triclosan.