We report a general and facile method that permits the transfer (stacking) of multiple independently fabricated and nanoscopically thin polymeric films, each containing a distinct bioactive agent, onto soft biomedically relevant surfaces (e.g.,
collagen-based
wound dressings). By using
polyelectrolyte multilayer films (
PEMs) formed from poly(allyl
amine hydrochloride) and
poly(acrylic acid) as representative polymeric nanofilms and micrometer-thick water-soluble poly(vinyl alcohol) sacrificial films to stack the
PEMs, we demonstrate that it is possible to create stacked polymeric constructs containing multiple bioactive agents (e.g., antimicrobial and antibiofilm agents) on soft and chemically complex surfaces onto which
PEMs cannot be routinely transferred by stamping. We illustrate the characteristics and merits of the approach by fabricating stacks of Ga3+ (antibiofilm agent)- and Ag+ (
antimicrobial agent)-loaded
PEMs as prototypical examples of agent-containing
PEMs and demonstrate that the stacked
PEMs incorporate precise loadings of the agents and provide flexibility in terms of tuning release rates. Specifically, we show that simultaneous release of Ga3+ and Ag+ from the stacked
PEMs on
collagen-based
wound dressings can lead to synergistic effects on bacteria, killing and dispersing biofilms formed by Pseudomonas aeruginosa (two strains: ATCC 27853 and MPAO1) at sufficiently low loadings of agents such that cytotoxic effects on mammalian cells are avoided. The approach is general (a wide range of bioactive agents other than Ga3+ and Ag+ can be incorporated into
PEMs), and the modular nature of the approach potentially allows end-user functionalization of soft
biological surfaces for programmed release of multiple bioactive agents.