Poly(lactic/glycolic acid) (PLGA)-based polymers have been extensively investigated as promising carriers to control the release rates for various types of pharmaceutical agents. In this study, we employed an atomistic molecular dynamics (MD) computation approach to quantify the Flory-Huggins parameters between poly(lactic acid) (PLA), poly(glycolic acid) (PGA), and tetracycline-HCl (TC-HCl) drugs, which can elucidate the thermodynamic stability and the interaction between drugs and PLGA polymers. Thermodynamic analysis regarding the miscibility and the stability of PLA, PGA, TC-HCl phases were then conducted in line with the experimental fabrication of polymer-drug films of two different copolymer ratio products, i.e., 50/50 (PLA/PGA ratio) and 75/25 PLGA samples. Meso-scale computations using phase-field method (PFM) were also conducted to predict the structural evolution of PLGA/TC-HCl systems using the calculated FloryeHuggins parameters. The results show that the surface morphology of PLGA/TC-HCl film can be highly dependent upon the thermodynamic interaction between the polymer and drug phases. (C) 2015 Elsevier Ltd. All rights reserved.