The determination of the bonded terms (bond, angles, and dihedrals) between adjacent CG beads was achieved after matching via an iterative procedure the bond distributions extracted from CG and UA simulations from previous work . For the PLGA parametrization, 40 chains with N = 16 were simulated for 300 ns at 330 K, which is right above the PLGA experimental glass-like transition temperature (315-320K) , to favor chains mobility and improve the sampling of the bond distributions. Considering the long relaxation time of the PLGA chains in a homopolymer melt, the bond distributions of a PLGA chain with N = 64 was also sampled in acetone for 100 ns at 300K. The atomistic trajectories were converted into a CG trajectory by assigning the COM of designated group of atoms to MARTINI beads according to the mapping strategy defined above. Bond and angle distributions between COMs of selected bonded beads were extracted from the target atomistic trajectory using the GROMACS routines "gmx distance" and "gmx angle", respectively. The computed average distances and angles were thus chosen as equilibrium lengths and angles for harmonic and harmonic cosine functions describing the bond, angle and dihedral interactions between CG beads, respectively (the equations describing bonded interactions are reported in Figure ). The force constants in the same equations were chosen as to reproduce the widths of the target atomistic distributions. CG parameters were adjusted by trial and error to reduce the mismatch between CG and UA distributions (Figures ). The stereo-regular effects associated with the presence of both D and L enantiomers of lactic acid were integrated into the calibration of dihedral angles.