Pneumonia is caused by microorganisms that settle in the lungs, which may reach the pulmonary alveoli and cause respiratory failure. Antibiotic treatments are the most used. However, their use may not be efficient due to bacterial resistance. The antimicrobial peptide BP-100 is a promising candidate for a new antibiotic due to its low susceptibility to bacterial resistance. It can be most effective when used with gold nanoparticles (AuNPs) and polymer coatings for topical use. The goal of this work was to evaluate the effect of the transposition of the BP-100 peptide carried on a gold nanoparticle coated with three types of polymers (polyethylene glycol (PEG), polystyrene (PS) and polyethylene glycol-block-polystyrene (PEG-b-PS)) using a pulmonary surfactant model. The Gibbs free energies for nanoparticle transpositions are performed using coarse grained molecular dynamics (CGMD) and umbrella sampling. The results demonstrate that the process is spontaneous for the gold nanoparticle containing BP-100 adsorbed on the AuNPs encapsulated with PEG. However, it is observed that the BP100-PEG nanoparticle breaks up when reaching the aqueous phase. Then, BP-100 migrates to the polar heads region of the negatively charged phospholipids. It is possible to evaluate the effects of nanocarriers on the lung surfactant model. In addition, it is suggested the feasibility of applying antimicrobial peptides carried on PEG capped AuNPs for possible treatments of lung diseases, such as pneumonia.