Density functional theory and molecular dynamics studies on electrical, mechanical, and thermal properties of TiO2 nanoparticles interacting with poly lactic-co-glycolic acid

Poly-lactic poly-co-glycolic acid (PLGA) copolymer is widely used thanks to its biocompatibility, even if could be difficult to find desirable mechanical properties for the polymer matrix. For this reason, inorganic nanoparticles like titanium dioxide (TiO2) can be used to modulate the mechanical properties of systems maintaining their biological capabilities. In this concern, density functional theory (DFT) and molecular dynamics (MD) simulations have been used to study the absorption phenomena of PLGA on surfaces of I41/amd (Anatase), P42/mnm (Rutile), and Pbca (Brookite) polymorphs of TiO2 DFT results showed that Anatase TiO2 is the best choice to absorb PLGA in comparison to the other PLGA-TiO2 surfaces. MD simulations remarked a peculiar stabilization pathway of PLGA-TiO2 with Anatase surface along the MD time and the largest increase in both Young's and Bulk's moduli. Finally, the influence of temperature on the mechanical properties of PLGA/A-TiO2 has also been investigated; in particular, MD results revealed that Young's modulus of nanocomposite and the binding energy decreased by increasing the temperature. The outcomes of the present investigation could be helpful to clarify the potential uses of the PLGA-TiO2 nanocomposites in the biomedical field ranging from bone tissue engineering to drug delivery.